There's been a bit of history so far with my current problem...so let me start from the beginning...
Chapter 1 : New (to me) Bike, Becoming RoadworthyI bought my first bike (a 2005 GS500F) used with about 16,500 miles on it. I was going through the normal routine checks on it with the Haynes manual and checking/fixing everything I was able to (air filter, spark plugs, oil filter, etc.). For the most part there wasn't too much to fix, the major things were a replacement front master cylinder, change the spark plugs, some worn fuel hoses (that I ripped while removing the gas tank for the first time) and some brittle plastic at the carburetor (the fuel intake T junction piece, broke as I replaced the fuel hoses...and some of the plastic possibly fell into the carburetor, not entirely sure). The master cylinder was no problem at all, the fuel hoses were a pain in the ass but only because I didn't remove the carburetor at this point, and the broken T junction broke with enough still intact that I was able to put the fuel hose on it still.
All of this was a pain in the ass, but was ultimately a great first experience in working on my own bike. Before buying, I had made the decision that I would do as much work on the bike as I could before going to a shop; not only to save some cash in the long run, but because I've been putting more importance on self-reliance in this area. There's no real reason for an engine to be a "black box" that I know nothing about, and starting off by doing everything needed on a running bike seemed to be a great way to jump in. So even though it was a pain, it was equally rewarding as my bike was finally able to get on the road enough that I was able to put about 100 miles on it...
Chapter 2 : The IncidentNear the end of those nearly 100 miles, I was had pulled up to a red light and everything was totally fine, but I was in minor traffic and wasn't going more than about 35 or so. I stop and prepare to turn right, the light changes to green, so I try to take off like I would normally and I find that I have essentially no power and plenty of sputtering. I was able to get back up to about 35 or so, but that was about as much as the bike wanted to do. Extremely convenient while I'm in a 55 mph zone... Lucky for me, I was able to quickly find a place to pull off the highway and take a look at everything.
My initial thought was that my gas lines weren't on as well as I had thought around that broken T piece, and that had come loose or something. I was able to easily look and see that there were no fuel leaks and everything was as dry as it should be, and the lines themselves look good. My next thought was that possibly the T piece plastic that might have made it into the carbs actually did, and had finally caught up with me. Either way, I was not having a good day at this point.
The only other thing to mention in this event, was that I was carrying my security chain under my seat, but I apparently hadn't secured it completely and it started to slide out while I was riding and drag behind me. I find it highly unlikely that this is related, but I also find myself very lucky as to not have had that get wound around something around the back wheel...
Chapter 3 : Trouble...shoot!I was able to limp it back home without any further incident. I stopped a few times to check a few other things, but at this point my major problems were:
- Poor acceleration
- Top speed of about 35mph
- Engine sounds "normal" and sounds like it's really trying to go faster, but it struggles to maintain 35mph (almost like a clogged air filter might act?)
- The engine was obviously missing, and vibrating/jerking more than normal when it would.
- The choke does not operate the same as it used to. Originally, the choke acted exactly as expected, after this incident it would no longer assist in my warm-up process and throttle was required when it really wasn't before. Originally, choke on at start, small blip of throttle, and it would take off to hold itself at ~3500 RPMs, and now it simply dies with or without choke.
Once I started in on it, I checked the obvious things based on my Haynes manual's troubleshooting section. Here's what I did following that:
- The air filter looked good and clean. It looked this way when I first got it, so I never replaced it. I even blew it out with an air compressor and seemed to have nothing notable come out of it.
- I finally received my replacement T piece for my carburetor, and since I needed to get into things and take them apart anyway, I decided to fully clean the carbs and change the o-rings/gaskets/etc. While blowing out everything, I never did notice any plastic come out...though it may be impossible to find via compressed air since it may have become a projectile... The carburetors seem to be in good condition overall and probably didn't even need that cleaning.
After this, my problems still persisted, so I contacted mechanic friends of mine (who were unfortunately all too busy to take on new work right now) as well as a local shop. The shop suggested that the problem might actually be my clutch, however, I remain skeptical. My mechanic buddies don't specialize in bikes either, so I'm not sure how much more help they would be in the long run anyway.
While working on the carburetors, I also broke a hose nipple on the CA emissions charcoal canister...the feed into the carburetor. This was another situation where I placed the hose over the remaining piece of nipple and secured it with tie-wraps since I'd have to special order that canister. Haven't done so yet simply because the fix seems to be holding fine, and it literally had zero effect on the overall symptoms of the bike.
After putting the carb back into the bike, I adjusted the throttle cables some and had to reset the idle screw. This improved my situation somewhat, but only enough that the engine wouldn't die as easily during warm-up and idling...the missing seemed to be reduced slightly from this too.
Chapter 4 : A New Lightbulb Clicks OnThe problem sat there for a little bit until this week, when I had more time to think, research, etc...so even though I "knew" it couldn't be a problem with my spark plugs (since I personally had put them in) I decided to pull them out anyway and have a look. It turned out, it was a good thing I did because I found new evidence, and somewhat solved some of the issue.
The spark plug on the left took very little effort to unscrew, and when I removed it it looked like a less-severe version of the Haynes manual picture for "carbon fouling" (dry, black sooty deposits). This was especially interesting to me since I had just replaced them recently, so I decided to check the other as well. That plug was also easier to unscrew than it probably should have been, but it was in a little better and had far less evidence of "carbon fouling". Also interesting to me that one side was worse than the other.
While I had the plugs out, I gently used a wire brush to clean off the carbon soot built-up on each of the plugs, then I made sure follow procedure exactly from the book to put them in. When I did this, I realized the difference from when I replaced the plugs originally...this time I had the right socket for my plugs...last time I had to "settle for" using a crescent since that's all I had that would do it.
This was some good news at least, since once I put everything back together and took it for another test ride, I had far better performance. My slow acceleration was absolutely still an issue, but the missing was nowhere to be found and given a long enough straight path I could probably slowly climb up to 50-60mph...I was saw the speedometer get up to about 45mph before I ran out of road where I was. This is far better than it was before...good enough that I feel I could bring it to a shop under its own power now, but still clearly not operating properly.
Chapter 5 : Where to go from here?...a.k.a. the TL;DRI've somewhat exhausted all of my knowledge and/or tools at this point. I'm not sure what else to try, or the things I can think of seem to be just wild shots in the dark.
I would absolutely love to fix this myself (or with skilled over-the-shoulder guidance, in the form of one of my buddies when they have time) rather than take it into the shop, just for the educational experience of it all, but I'm figuring I might need to just take it in since I also lack proper equipment.
This is the current symptom list:
- The Major Issue: Poor acceleration -- low and high speeds; low speed acceleration and performance drastically improved over the spark-plug tightening but still not "right". Opening the throttle completely does increase the "sound" of the engine but accelerates just about as slowly as far less throttle.
- Poor top speed, I think, because the engine seems to not be delivering the power it should...I haven't really tested the new maximum, but it's now more than 45mph when it used to be ~35mph or less.
- Neural switch, kickstand kill-switch, and headlight electrical issues have popped up...I believe these to be unrelated to the acceleration, and more related to me rerouting spark plug wires to come away from hot engine components...doing so brought it around some other electrical connectors that may simply be loose/broken.
Does anyone happen to have any ideas? I would think air filter except that it seems pretty clean currently. Valve clearances would be one I don't have the tools or confidence in myself to do yet, but something that seems to be possibly in need of adjustment too.
Any help would be greatly appreciated. Thanks in advance!
This sounds a lot like a slipping clutch to me. Have you checked your clutch cable? If it is a little too tight or you routed it wrong after working on the carb, it will not release enough to allow the clutch to fully engage. This would cause these symptoms.
#5161
The first thing that comes to mind - which you didn't mention - is....
Do you have enough gas in the tank?
Is the tank petcock all the way ON? (Slot vertical).
Even if you think you do have enough gas - fill it up. Maybe the fuel lines are reversed.
Then try running in PRIME if still a problem in case the vacuum line to the petcick is on wrong or has developed a hole in it.
Sorry I didn't read every word of your post, so I may be missing information.
Could be a clogged main jet in one of the carburators. Some seafoam or gumout in the gas tank can never hurt. If you have the mechanical knowledge, go ahead and take the jets out and check them for clogs.
89500inPA:
That was the diagnosis from the shop in town too...clutch issue. I can't rule it out, and maybe I cured all of the other engine issues by making sure the spark plugs were in good...not sure. The cable didn't really get disturbed much from the carb work, but that could still be it. Would any of this be something that could appear "all of a sudden" before any tinkering with the carbs?
adidasguy:
I'm pretty sure there's enough gas in the tank and the petcock is on during everything above. I've not had any change by switching this to reserve...unfortunately, probably not as simple as this, as much as I'd like it to be. :( Somewhere else in this forum I found that the Haynes manual diagrams (at least in one spot) were wrong for my model, but even armed with that knowledge it turns out I had everything correct anyway (I checked my routing against a Suzuki part blow-out diagram, which turned out to be correct).
The vacuum line on the petcock however...I hadn't even considered anything with that. I will analyze that closer for sure.
Bluesmudge:
The details in the post didn't really detail the carb work I put in...but it involved taking the jets out and making sure everything was fine there...everything to do with the carbs looked pretty good even before cleaning. I had considered throwing an additive like that through, but since I had just cleaned everything manually I figured it wouldn't probably get much that I didn't...especially since what I cleaned looked like it was already clean as it was.
I really appreciate the help everyone, for sure.
I think next, I'm going to go through the Haynes process of making sure the clutch cable is setup properly, just to be sure that's not it, as well as the vacuum line on the petcock. I guess I'm also wondering if it would just be a good idea to take it in to have the carbs sync'ed and all of that fun stuff I don't have the equipment to really do properly too. Is it possible that I just have a few things out of adjustment that are all just working against me at the moment?
Could be a couple small things all adding up.......
If it's a clutch issue, once you get to your top speed at WOT, the rpm's will continue to rise but you won't go faster. Sounds like you're running lean to me though (from what I skimmed thru on my phone). What jets do you have in now? And have you checked compression, valve clearances, and strong blue spark?
Pretty sure you have enough gas?
Dude, looking in the tank tells you Nothing. That's cause the tank Looks like there is plenty of gas when there isn't.
So, before you go Ripping anything apart, go fill the bugger up. And reset the trip meter to Zero when you do.
IF it solves your problem, ride until you hit reserve - loose all power again, blah blah - and have a look at the distance you have gone. At this point go fill up again, reset trip meter and repeat. Once you have two distances known, you have a good idea of the likely range you can get before hitting reserve.
Try filling up first, it's the easiest thing to check. Move on After that has been checked.
Michael
Big Rich:
What hints at running lean? The biggest reason I ask is that the Haynes manual suggests that carbon buildup on my spark plugs like that shows that it's running rich.
I'm not sure what jets I have in now...they're what I got with the bike. They may or may not be stock, I'm not sure if one of the two previous owners did anything with them or not.
I haven't checked compression or valve clearances...those were things I'd figure I need a shop to look at, at least for now. I was wondering about these things too though.
mister:
The only reason I haven't mentioned much about gas being an issue, is because this all started not long after I had filled up. During the course of working on it, I did end up setting down the gas tank at a bad angle that allowed lots of gas to drain, but that still left me with at least 1/2 of a tank. The reason I say "pretty sure" is because I never even looked in it...I've simply had the gas tank off so many times recently that I can feel the weight and slosh of the gas in there. I'm "pretty sure" that I've still got at least 1/4 of a tank...but I don't have any real way to gauge it.
I'd love for this to be the problem, and nevertheless I'm still going to add fuel and try the various positions of my petcock to see if anything improves, hoping it will help. Since I am a relatively new rider, and I haven't really ran out of gas on the road...I'd have to imagine that if I weren't getting fuel because of needing to switch to the reserve that I'd only be able to have the thing run for a short time that way. Though, maybe adidasguy is onto something with the petcock itself being a potential culprit, which could result in similar symptoms for a longer duration than expected.
Well...I'm off to check clutch and fuel systems. I'll post any new info if I come up with anything notable. Thanks again everyone for the ideas. Every little bit helps. :)
I had a problem identical to this. It was ALL carb related. Clean those things out, clean your plugs again and I bet it will be fine.
Just adjusted the clutch cable to be sure that isn't an issue. Having it start up and idle seems to be no problem at all in either on or reserve on my petcock. In a short while (currently blocked in by other vehicles), I'm going to cruise over to the gas station and put some gas in it just to be sure and test drive a little more to see if problems persist.
xanthras:
This whole time, I've been leaning towards that as my issue too. I'm still not completely convinced that there isn't a small piece of plastic stuck inside the carbs somewhere from when the T broke, restricting air or fuel flow or something...even after blowing everything out with carb cleaner, compressed air, etc. I'd rather not do this again, but I too can't rule this out...though it might be better for me to take it to a shop to have the carbs sync'ed and have the mixture checked and all of that fun stuff too.
Was the bike sitting a long time before you bought it, as in longer than a month? Since you have only done 100 miles, I bet there is plenty of gas from the previous owner in there.
I ask because, if it is e10 gas then it could have easily gone partially bad in that amount of time. When I spent 2 months rebuilding my engine this winter and then tried to use the same gas that had been in the tank, I caused another month of trouble before I fully emptied the tank and put in fresh gas. Just because the carbs are clean when you put the carb back together, doesn't mean that they won't just suck more crap into them as soon as you start it up. Been there with two bikes now.
So, just as another thing to rule out, dump out all that old gas, fill it up with some fresh stuff, splash in some gumout, see how it goes.
Actually, a good way to help diagnose this -- see if it only bogs down under load. Put bike in neutral, let it warm up, then try to rev it to redline. If it revs just fine when not under load, then you know its not a carb problem.
Bluesmudge:
The owner before me claimed to use it as his normal ride to work. He did bring it to me full, but while I was dealing with my initial fuel hose problem, I ended up slowly emptying my tank overnight because I left it sitting at a bad angle...had to replace that complimentary full tank very early on because of my ignorance and lack of forethought (I mean, I really should have just checked the damned thing before leaving it overnight :P). I've only been to the pump once so far, and today will make twice with it.
I'm also glad you mentioned something about revs in neutral. I wish I would have mentioned this earlier since I did mention it to the shop when I called them, but the problem has only really shown up under load. In neutral, it sounds essentially perfect. Since I got the plugs back in and fired it up yesterday it has sounded probably as good as it ever has. I can smoothly go from idle to redline once it's warmed up and it sounds great every step of the way...this wasn't the case before pulling out and checking on my spark plugs. I was probably mislead to the carburetor because of my spark plugs, and now that those are secure and the engine sounds great in neutral...again I'm being pointed clutch-ward.
It sounds like it is/was probably multiple issues in concert...but it looks like the problem is being narrowed down at least. I've just rechecked the clutch cable and adjusted the freeplay to rule those out. If I take it out and still have the problem (which I'm assuming I will), it looks like I'll probably have to gear up for a clutch job.
I suggested running lean because of the 45mph top speed. If an engine just feels like it hits a wall, it can be running extremely lean. You said you one spark plug is fouled? It could be only running on one cylinder as well. That could also explain the low top speed / revving fine in neutral. Next time you have the tank off swap the coils left and right and see if the opposite plug becomes fouled.
Big Rich:
Gotcha. Didn't know running extremely lean would act that way. Good to know.
I had one plug fouled, and that was the plug that was in loose too (they both were, but that one was just barely tool-tight when it needed at least a 1/4 turn)...it probably was running on one cylinder for a bit.
I'm still blocked in, otherwise I'd have new info at this point, but the vehicle blocking me is also down for repairs...d'oh! Kinda stuck at the moment (it's horribly hot though, so it's not all bad, I guess).
I've been thinking though, and I wonder if I might have had a problem with my spark plugs coming loose that gave me my initial problem, and in the process of (probably unnecessarily) working on the carburetors, maybe I changed the routing of my clutch cable enough to add too much tension; just enough tension to make the clutch never completely get released, as if there weren't enough free play. When I made adjustments earlier today, it didn't seem off, but I went through with the Haynes procedure anyway and reset the adjustment at the handlebars then set the free play on the cable at the clutch side. I'm hoping to at least see an improvement with this, but we'll see.
Well, finally got out for my test drive again... I wasn't able to really get fast enough to test this before, but since I was able to get a higher top speed while I was out, I was able to find out that engine breaking was effective only sometimes; usually the faster I was going, the more of an effect it would have (not too abnormal yet, bear with me). The part that got weird was at slower speeds. It would feel like there was essentially no effect for engine breaking with gears 1-3. If I got it up to 5th gear and came down, there would be a noticeable engine break as I went to 4, but from 3 down to 1 I might as well have not really been engine breaking at all.
Based on this, I'm going to have to say that I probably had multiple problems overall. A spark plug problem and a clutch problem, and a possible minor electrical deal thankfully now only affecting the neutral light on the handlebars.
Thanks everyone for all of the suggestions. I'll resurrect the thread if for some reason a new clutch doesn't resolve things...but I'd bet that's it.
You guys rock. :)
Keep us notified, I am intrigued by your problem and you I bet we would all love to hear once you get it fixed!
stokes776:
No problem!
I realize now too, I forgot to add a few things I noted from my last test drive...
My throttle had an effective range of about 1/4 (or possibly less) of the throttle. If I rolled it on any further than that, it would simply sound like it was trying harder but not really moving faster.
I took some advice found somewhere else throughout the forum, and I got the bike up to about 35mph, and then I shifted up 2 gears from 3rd to 5th, and then tried to proceed as if it were a single gear change. I was expecting some lurching, chugging, or some other non-normal outcome from the bike, but instead it seemed to shift right into 5th without trouble; very smooth.
Also, the operation of my choke smoothed out completely and no operates much better than when I originally purchased the bike. This had to have been all part of the spark plug problem.
The smooth "bad" shift combined with engine breaking being very ineffective (especially compared to normal), is really what made me order new clutch plates and decide that was my biggest issue at this point. Honestly, I expect that this will be my last issue for now, and things will be operating better than usual. They will probably get here early next week, but while I'm waiting on that, I'm going to trace my neutral light to figure out why that decided to stop working again...
Update!
My clutch plates arrived yesterday, so I threw them into some oil over night to prepare them for today. I ended up getting both the friction plates and the smooth plates as well as new springs, and just replaced everything. The gasket was in horrible shape, the friction plates were obviously worn (some more than others, perhaps the reason for the lack of power in the first place), the smooth plates seemed like they were in good shape still, and the springs seemed to be in pretty good shape, but obviously slightly more worn than the new ones I was putting in. Everything went pretty much as smooth as expected (removing that old gasket is a pain in the ass...though it was expected). I put everything together, adjusted the clutch cable, and got everything going pretty much perfect....or so I thought.
I took it out for at test drive, and I found that it was slightly better, but not all that much better than before. It took less "babying" to get it up to speed, and I was able to hop on the freeway and get up to a maximum speed of 69mph on flat ground. When I started to bring it back home, I noticed that my clutch lever was loosening. I figured that I probably didn't get a lock nut down all of the way...which is probably at least partially true...
I pulled the clutch release cover off, and went to loosen the lock nut and adjust the clutch release adjustment screw, but this time I noticed that I must have damaged the screw earlier: the place where the flat-head screwdriver goes into the screw was partially stripped in one direction (tightening has full grab, loosening is stripped, but not so bad it can't be used). I tried to get the lock nut loosened and I couldn't budge it at all, so I loosened the screw and nut together and tried to tighten the nut further down the screw but it wouldn't move either direction...the lock nut is now effectively secured at the end of the screw, probably because of the stripped bolt.
So, for the mean time, I simply tightened the screw+lock nut down secure again, and I must have got it slightly better than I had before because when I took it for another test drive, instead of only having about 1/4 throttle with actual power, I now had power up to about 1/2 of my throttle -- Progress!
My plan now, is to replace the clutch release adjustment screw and its lock nut, and I presume that once I can get that set properly, my problem will probably be completely resolved. Does anyone know if I can just back this screw all of the way out and pop a new one in easily? I'm strongly considering, and will probably create a replacement screw/lock nut from whatever is available at Home Depot of the same size/threading/metal, rather than ordering a new one and dropping $10+ on shipping to get a $1.75 screw and a $1.25 nut for it...
Unfortunately, when I pulled it back into the driveway though, the engine died and now it doesn't even try to start...it almost acts as if there is only a slight charge on the battery, or if the engine kill switch were on because I don't even hear the starter try to turn over at all...no sounds at all, but I get my oil light on the console. I'm guessing this problem is related to my other electrical issues that have started to pop up...
Good progress, seems like I'm narrowing down the issues and learning a ton about the bike in the process. Gonna cross my fingers and hope for the best for tomorrow.
Just because lights come on and horn may sound does not mean the battery has enough oomph to start your bike. If you have a charger, pop the battery's caps, make sure enough liquid is in them, and charge it up.
If your battery is not charging while you are riding, all spark, lights, indicators, etc., will be drawing from the battery and eventually flatten it.
Michael
mister:
Yep, that was my initial thought too. I'm just assuming the worst since one of the previous owners did a few customization with the electrical (new headlights/tail lights/turn signals/etc.) and it's kind of obvious that the job wasn't perfect. I typically start with the easiest and most likely thing first though (like charging the battery). Now that I think about it...the battery was another upgrade...it's an aftermarket solid-state battery of some kind. It at least eliminates the possibility of liquid in the battery, etc.
I guess my biggest unknown at the moment (that I guess I'm probably just going to figure out in a few minutes) is if it's okay to just back out that clutch release adjustment screw all of the way and pull it out or if that will somehow be detrimental. It seems like it would be alright, but I'd hate to find out that I have to pull off the crankcase cover to reassemble something because that screw was no longer holding it in place. ;)
Another update.
My clutch adjuster screw got replaced (had to go to a specialty bolt shop to get the exact bolt, but at least I didn't have to craft it myself) and reset. I adjusted the clutch cable afterward to have the proper amount of freeplay, as directed in the Haynes manual.
My battery problem ended up being a bad cell in the battery. I charged it overnight and still had the same problem in the morning, so I took the battery in to a battery shop to get tested. I opted to buy a new battery online since the shop didn't have anything comparable to my old battery, and it was only going to cost me an extra $2 and 2 days waiting time to get the exact same thing, so I decided to do that instead. Having a maintenance-free battery was totally worth the extra cost in this case.
My test drives seem to have consistent performance at low speeds, but acceleration and top speed are still suffering somewhat. I'm at a point where I can get around in normal city traffic, but I can't rely on acceleration or freeway speeds to be there when I need them. After just a few miles and back home again, I noticed that my clutch lever was starting to loosen a bit; not as bad as the last test drive before I replaced that adjustment screw though... I feel like I must not be getting that down tight enough, and I'm guessing it's because it's somewhat spring-loaded...I probably need to take more care to be certain it's as tight as it should be. And, just to be sure I'm doing it right, these are the steps I'm taking to adjust that screw:
- Take off the 2 screws on the cover, and remove the cover
- Loosen the lock nut
- Loosen the adjuster screw by several turns, then tighten until I start to feel some resistance.
- (This is the big question:) Am I supposed to just barely, barely, barely notice resistance and then back the screw off 1/4-1/2 turn from there? Or do I screw it in until I feel resistance on a normal turn of the screwdriver, then back it off? -- I seem to be having slightly better results by the latter, but I'm not 100% certain on this. Should the adjustment screw normally be in contact with the pushrod? Or is the goal to be ever so slightly off of the pushrod?
- Once I set the screw, then I tighten the lock nut again...this part seems to give a somewhat false sense of locknut tightness because of the clutch release mechanism itself... As mentioned before, I believe this is the reason my clutch cable is loosening slightly while riding.
- Replace the cover.
- Release the lock nut on the clutch cable adjuster on both the handlebars and the clutch and loosen the cable.
- The Haynes manual recommends to give maximum freeplay at the handlebars and adjust at the clutch end, so that future adjustments can be made at the handlebars...so I adjust the handlebar side accordingly and lock it with the lock nut, then adjust the freeplay at the clutch.
- Once the freeplay is set appropriately, I lock the lock nut on the clutch side.
This process results in what feels like a good, normal clutch feel...so it seems at least mostly correct. The big question really is how to back off the adjuster screw appropriately. I'm assuming that if I have the bike on the center stand, and I put the bike into gear that while holding in the clutch there should be absolutely zero movement of the rear wheel -- if there is movement, the clutch is too tight, correct?
Could my clutch still be causing my acceleration/top speed issues? I wish I had time to get familiar with the bike before I had this trouble with it...because I'd swear that it sounds somewhat air-starved, as if I needed to replace the air filter. I'm really tempted to just replace it at this point anyway just to be sure, but I'm not sure it would solve my problem. I'm also wondering if I might have accidentally done something to my carburetors (like accidentally adjusting the float height, or something) when I cleaned them.
I forget.... did we rule out the presence of an after market fuel filter?
Michael
mister:
The fuel filter on it looked like the picture in the Haynes manual. The only time I looked at it was when I initially started checking things over on the bike when I first bought it. At that time, it looked like it might have been brand new.
Nicro - please take this in the kindest way possible. But your responses tend to be a little bit long winded. Try and understand: I'm almost always on my phone so it's kind of hard already to read the screen. Details are good though and I understand your reasoning...........
What happens when you reach your current top speed? Does the engine feel like it just hits a wall and doesn't have power? Or does the motor continue to rev higher and higher but the speed does not increase?
Ok, I'm not talking about anything Inside the tank. I am talking about a fuel filter anywhere on a fuel line between the undertank petcock and the carbs.
Michael
BigRich:
The best description would be like hitting a wall. The revs will increase slowly with my throttle between 1/2 and full until I climb up to about 70mph, and then I can get it to output anymore. Dropping or raising a gear simply changes the RPM range it works in when at top speed.
mister:
There are no additional filters in-line anywhere. From the tank, through the filter there into the hoses and to the petcock, then from the petcock straight to the carbs.
Sorry about the "windedness" of the posts...I just figure it's better to err on the side of too much information rather than me not share some critical piece of info...something I might think of as trivial could be the most important thing of all so I just don't want to leave anything out. Fresh update posts will probably always be the longest, but I'll try to keep them more concise.
What is the max rpm you are able to get the bike to? In Any gear?
Michael
mister:
I can take it to redline nice and smooth in neutral. I can take it to redline in 1st and 2nd, possibly 3rd, but it starts to taper off. Last test drive, I believe I was on the freeway in 6th, full throttle, RPMs at around 7-8k. If I drop to 5th, full throttle, my RPMs are around 10k instead. The feeling on the throttle, is that I can roll it off at least 1/4 - 1/2 before it actually starts to decelerate.
Ok, so if I'm following correctly... you're getting a top speed of 69mph which is 110kph but you're redlining at 7-k in top gear to do this. Is that right?
Ok.... for reference with rpm you should have....
4th gear, 4,000 rpm close to 37mph
4th gear, 9,000rpm close to 87mph
6th gear 5,000 rpm close to 62mph
6th gear 6,000rpm close to 75rpm
If you're revving much higher in those gears for those speeds apart from something slipping I'd be checking your sprockets. I don't remember if you said they were stock 16 front and 39 rear or not.
Michael
mister:
I'm actually not quite sure what configuration the sprockets are in right now. The guy I bought it from had 2 sets, one set that he said was better for "around the city" and the other was better for "freeway stuff". I'll check that.
Thanks for the reference...I'll take it for another drive and get more exact results to compare.
Beyond cleaning the chain and examination when I first got it, I haven't really checked into that again at all. Would it be possible for a chain that has too much slack to cause this kind of a problem too?
Also, on the clutch release adjustment screw...just to be sure...I'm supposed to screw that in until I barely feel something and then back it off so it isn't touching the pushrod inside, right? I just want to be sure that I'm doing that right, since that's the only part of the clutch that wasn't completely straightforward.
Glad you took that the right way. You're right about people leaving out important info too though.
Sounds to me like a carb or electrical issue now. Maybe a kinked fuel line, clogged gas cap vent, clogged carb breather, etc. Or just a weak spark from a dirty connection somewhere.
Quote from: mister on August 11, 2012, 03:27:32 PM
Ok, so if I'm following correctly... you're getting a top speed of 69mph which is 110kph but you're redlining at 7-k in top gear to do this. Is that right?
That sentence is an oxymoron. Redline by definition is 11k, not 7k.
Quote from: Phil B on August 11, 2012, 08:22:14 PM
Quote from: mister on August 11, 2012, 03:27:32 PM
Ok, so if I'm following correctly... you're getting a top speed of 69mph which is 110kph but you're redlining at 7-k in top gear to do this. Is that right?
That sentence is an oxymoron. Redline by definition is 11k, not 7k.
Thank you Phil. Of course your astute observation does not help the OP with his problem, but I will be certain to watch my phraseology around you in the future.
So let me rephrase it so you can understand it better....
Ok, so if I'm following correctly... you're getting a top speed of 69mph which is 110kph but you're rpms are peaking at 7-k in top gear to do this. Is that right?
Is that satisfactory to you, Phil?
Michael
Big Rich:
My thinking has been with the carbs since the start... I still haven't been able to completely rule them out. Though, others have said that if the bike revs wonderfully in neutral, that the carburetors probably aren't the problem. I'm still not completely sold on that...but maybe it's just with lines/hoses that come to/from the carbs that I didn't clean out while I was in there or something, like you're suggesting.
Phil B:
I was pretty sure I knew what he meant, but thanks for the clarification all the same.
mister:
Your understanding is correct. Those figures are based on memory though, and may not be entirely accurate, but they're close at least. I just looked over my sprockets and the chain again, and everything looks to be in good shape. I seem to have a 16/39 sprocket ratio on the bike right now (with an extra 15 and an extra 39 as well; these sprockets look to be in pretty good shape too).
It's stupidly hot already today, so I'm probably going to wait until the heat starts to break before I hop on for another test drive to get better RPM/speed data for you guys.
Also, thanks again everyone for the help! I'd be hard pressed to do this myself. You guys rock. :)
Have you confirmed your carb slides are working by pulling the airbox and revving a bit in idle while watching them? If they aren't moving that would likely cause something similar to what you're describing. Make sure they move freely by hand too.
It's fairly easy for a motor to rev in neutral, since there's no load on the transmission (it's not using power to move the weight of the bike & rider).
I would start with the electrical side first: new spark plugs, unscrew the plug boots and trim the wires 1/4", clean and grease any ignition connections, etc. Do you have a decent multimeter?
Since it sounds as if you are running on 1 cylinder, start looking for differences between the carbs. Check that the slides move equally (as previously mentioned), all jets are clean (or new), all passages have compressed air blown thru them, and have your carbs synced. If you bench sync them, they should be REALLY close. A vacuum sync will get them spot on.
Badbot:
If it isn't outlined in the Haynes manual, I probably haven't attempted it... I did make sure they were moving freely by hand. I've been too much of a wimp to even turn the key to "on" without having all of the components back on the bike (save the obviously non-mechanical/electrical things, like fairings).
So, just to make sure... To check that, I'd take off the tank (but keep the fuel hoses attached) and put it aside, remove the air box, then fire up the engine and look into the back of the carbs? What should I see? What would I see if something were obviously wrong?
I was just talking with my dad about my clutch, and the more I think about it, the more I'm wondering if that clutch adjustment screw is just a large part of it. With my clutch lever getting loosened over short rides, and locking down that lock nut better provides me with 50% more power (at least in one instance)...I wonder if it's just coming out of adjustment as I tighten down the lock nut, especially since I apparently am not getting the lock nut tightened enough.
I'm going to take special care to make sure before I take it out this evening, and make sure that my clutch lever doesn't come lose during riding before I throw "clutch slippage" off the table. After that, I'll probably take a much closer look into the carburetors and related things again.
Big Rich:
The spark plugs have only been in the bike for about 150-200 miles. That being said, I did recently clean them off because they had carbon soot on them (the left was far worse than the right)...that's when I found out they were probably not in as tight as they should have been. At what point do I know I just need to get new plugs again vs. when the plugs are just a little dirty and they can be cleaned up and used?
I have a multimeter...just a cheap Harbor Freight meter though, but probably good enough to check over the electrical for the most part. I'm "in training" for this right now effectively, as I know this is where one of my other issues is, in the neutral light being out.
Quote from: NicroHobak on August 12, 2012, 02:50:34 PM
... as I know this is where one of my other issues is, in the neutral light being out.
Just as a place to start, have you checked if the bulb for the neutral indicator light is good? To check, you're going to need to get underneath the speedometer/tachometer cluster (just a couple of nuts on either side of the assembly) to get to the indicator bulbs. If your oil pressure light works (the red one), just switch out the bulbs between the oil pressure and neutral indicators, turn the ignition on, and with the bike in neutral see if the neutral light comes on. If it does, you have a bad bulb. Or, if you want to use the multimeter, remove the neutral bulb and see if you get around 12V between the socket contacts with the ignition on.
And how does each plug look right now (after using them)? If the left is still sooty, then that's isolating the problem a little. I can't say with any certainty when plugs should be replaced, but even new plugs can have problems (just ask Adidasguy).
If your plugs don't look identical, try swapping the left and right coil / plug wire / boots / plugs and see if the problem follows.
Another update...
So, I'm convinced that I wasn't setting the clutch release adjustment quite right... But I was able to tinker with it and drive, tinker more and drive, and I figured out what the proper adjustment should actually be, and what the adjustment is actually doing. I now can say for certain that I know how to adjust where the friction zone happens*, as well as the freeplay of the clutch cable. After some adjustment, I was able to gain more power while accelerating, and I was starting to notice slipping at high speeds. Now everything is adjusted so I can't feel slippage anymore, the clutch's friction zone is right around the middle of the clutch lever travel space, and the proper amount of freeplay is in the cable.
I'm also fairly sure that my clutch lever loosening problem was found too...apparently I forgot to re-lock the lock nut on the clutch cable at the clutch lever end...covered it up with the rubber without locking it down, and I never happened to see that as an issue... It looks like my clutch release adjustment was indeed getting tightened enough after all.
After checking RPM's against what mister posted... It seems that I'm right in line with some of it at least. If I get up to ~40mph and shift up to 4th, I cruise at around 4k RPMs. If I gain speed in 3rd first, and then shift to 4th at around 60mph, my RPMs settle in at around 6k, and I will still gain speed, albeit extremely slowly until the RPMs get to around 7.5k-8k when it seem to not have anymore power.
Taking off from 1st seems slightly sluggish until RPMs get up to about 4k or so, then it accelerates exactly like I would expect for the rest of 1st gear, 2nd gear, and all of 3rd gear. It's once I get upwards around ~60mph that my power goes away.
I'm starting to believe that I'm getting the clutch issues resolved, and that there's simply another issue still lingering as well. I'll pull the plugs and have a look at those again and try swapping them, etc. and blowing out the carbs (and related hoses, etc.) with compressed air, and I'll find some clear hose to check float height, and all of that fun stuff...then again, maybe it's now time to just resolve the electrical and get that problem behind me with certainty as well.
*Your friction zone is what is adjusted by the clutch release adjustment screw. The Haynes manual is unclear as to what resistance point to go to, as well as what that backing off 1/4 to 1/2 turn does. With a little bit of testing, I think I've "cracked the code". I'd love review by someone more knowledgeable, just to be sure I'm not misdirecting anyone (including myself), but if you are intimately familiar with your bike/clutch/etc, you probably won't care to read on...fair warning. ;)
Here's what the Haynes manual essentially says:
When setting the clutch release adjustment screw (under the small panel secured by 2 screws right above the clutch lever), loosen the lock nut and loosen the screw several turns, then tighten until you feel some resistance, then back it off 1/4 to 1/2 turn and lock the lock nut.
Here's what extra information I found out:
When tightening the adjustment screw by hand, you can feel 2 points of resistance: 1 somewhat subtle point when the screw first makes contact with the push rod, and 1 much less subtle point when the screw starts to tighten the push rod into the clutch. I tried first by setting the screw at point 1 (the subtle resistance point) and I found that I had to pull the clutch lever almost all of the way to the handlebars to find my friction zone. I then brought it back home, and set the screw at the 2nd point (the far less subtle point of resistance) and went out riding again. This time, I found that my friction zone was almost immediately after the clutch lever's freeplay was out.
My personally updated guidelines of how to set this screw, based on all of the above:
- Loosen the lock nut
- Loosen the adjuster screw several turns, to be sure it is absolutely not in contact with the push rod
- Slowly tighten the adjustment screw by hand, until the slightest amount of resistance is felt -- Mark this as Position 1
- Continue to tighten the adjustment screw until very obvious resistance is felt -- Mark this as Position 2
- The distance between point 1 and point 2 might be roughly 3/4 of a full turn of the screw -- this distance is analogous to your clutch's friction zone. Right in the middle of position 1 and position 2 should require the clutch to be pulled in about 1/2 way. Going closer to position 1 moves the friction zone to your handlebars (requiring more applied force), and going closer to position 2 moves the friction zone away from your handlebars (requiring less applied force)
- Set the clutch release adjustment screw to your approximate preferred location, based on the above
- Hold the adjustment screw in place as you lock the lock nut into position, making sure to tighten appropriately
- Adjust the freeplay in the clutch cable as you normally would -- Since you're here with your tools, I'd recommend to adjust the cable at the handlebars to have the maximum amount of slack, and then adjust the freeplay at the clutch end of the cable. (This is actually the Haynes manual suggestion, but it makes sense, I think!)
- Make sure to lock the lock nuts at the handlebars and the clutch sides of the cable -- failure to do so will make your clutch lever go "squishy" while riding!
Another update...
Good news and bad news...bad first...
Stranded at the moment, waiting on a jump start. It appears that my brand new battery isn't getting charged like it should. I'll know for sure once some jumper cables arrive...
Good news though, is right before this ride I decided to go through and recheck everything I had been messing with, especially related to the clutch, and I found that the clutch cable was actually backed out of the engine case...it seems THAT was the real cause of my clutch cable loosening, etc.
Correcting that seemed to somewhat resolve (or at least once again improve) the situation. I'll know a little better once I can get it on the freeway though.
Well, I just limped it home... It wasn't the battery after all, though I'm not sure why the starter wasn't turning over at all when I first died.
So, I was driving along, then I started to get jerking motions before it just died when coming up to a stop (once I pulled the clutch all of the way in for longer than about 2 seconds). I restarted it, got part way down the next street and it started doing the same thing, so I flipped my petcock to reserve (even though I've only gone 83 miles since I last filled up), and as I expected it didn't change anything really.
Shortly after that, it died on me, and I couldn't get any activity out of the starter. The first time I tried while I was still moving; clutch pulled in, still going about 35mph, starter doesn't even turn over (everything is just silent). Since I still had momentum, I was able to coast into a parking lot. I again tried to start the bike, but there was nothing from the starter. The oil light was on, the head/tail lights were on (I still haven't fixed my neutral light though...shame on me :( ...), but no activity from the starter.
It turned out, the parking lot was a slight slope, so I tried to push start it -- no luck. At this point, I pulled into some shade, tried the starter one more time and then made the previous post.
After waiting a little bit and checking over everything for any obvious signs of trouble but I don't see anything in particular, so I just decided to browse the forums while I waited...quickly got tired of the heat, and so I decided to try it again.
Amazingly enough, the starter was turning over again and after a little coaxing, I was able to get it started and out on the road again towards home. However, on the very next block, I started to hear some backfiring and it ended up dying right as I pulled up to the next light... The better news this time, was the starter was still trying its damnedest, but it just couldn't get the engine started.
I limped it home like that...having it die, me working on getting it started via push starts and/or using the starter and crossing my fingers. It basically died at every intersection where I had to come to a full stop and had the same issue, and even while riding, it was a rough ride with backfiring...
I'm going to pull my plugs right now and check on them... But in the mean time, is there anything obvious that this behavior would suggest?
Plugs looked to be in exactly the same condition as when I last checked. It still won't really get going, though now it seems to try every time. Seems pretty fishy that it happened right after getting the clutch to a point where I felt like it was possibly "normal"... It makes me wonder if getting the clutch fixed is making my old, original problem come back...and maybe it wasn't even loose plugs after all.
I'm starting to suspect electrical on the bike enough that I've scheduled tomorrow to just check over all of the electrical on the bike. Will report back once that's done.
To check the operation of your carb slides, fire the bike up with the filter/airbox off (make sure there's nothing loose nearby and it's not really dusty, naturally) and rev it a bit, looking into the filter sides of the carbs. You should see the slides move at least a tad bit up and down, and they should move equal amounts (but not synchronously). More airflow should mean the slides go higher. Be careful not to over rev or overheat the engine.
As far as the clutch adjustment goes, at least on my '91 - I haven't bothered getting at the adjustment on the side of the sprocket cover, but there's an adjuster/locknut on top of the sprocket cover (cable passes through it) as well as one with a thumb nut under the rubber cover near the lever. So long as the clutch lever has wiggle room (maybe half an inch or more at the tip) between being all the way out and where you feel it actually pulling on the clutch you should be fine so long as your clutch doesn't drag when you have the lever all the way in. Anywhere in between is a matter of preference, although someone will probably come along and quote factory specs.
With bike sputtering and dieing, since you mentioned replacing the fuel lines check your routing. Make sure that the lines aren't too long or sitting up against parts of the engine, you may be boiling off your fuel in the lines. Also, double check that there aren't any kinks. If you experience the problem again, first pop your gas cap, let it sit for a couple seconds on prime, and see if it will start again. If not, close the gas cap and let the bike sit for 10 minutes or so to cool down and see if it will work then. While you wait, pull a plug boot, put a piece of metal in the boot, and bring the metal close to the engine or frame and crank it with the starter to test for spark.
On the starter not working - It may be something to do with the clutch safety switch since your clutch was out of whack before. I've also had the odd, rare instance of my starter not working, but as soon as I turned the engine a bit by pushing the bike a few inches it's worked fine -- you may have done this trying to push start it.
Badot:
Checking the carb slides will be on my list of things to do tomorrow. Thanks for the info on that.
I was making adjustments in all 3 clutch adjustment places. The adjustment at the engine case was the one that was unscrewed completely. It was still held in place firmly because of the cable...what finally tipped me off to there even being a problem was when I made another minor adjustment to it and the lock nut didn't tighten...it just pulled the thing out instead. Whoops. I honestly don't know how long that was like that, but it was probably from when I first adjusted the thing.
You mention the fuel lines... Funny that I was thinking about that too. After looking at many posts here, it looks like I may very well have my hoses backwards. I got the routing from the Suzuki parts diagram blowouts, but posts here disagree with that -- I'm more inclined to believe you guys at this point too. From another post, I found that the tank petcock has an 'R' at least, and possibly an 'O' to help...I was going to hope to see these marks on the main petcock and match that way.
Also, when I looked in the tank a little earlier (because a visual inspection is always good), it looked like the fuel level might low enough that I might be right at the on/reserve cut-off point too. There's obviously fuel in it, but as others have said, that can be misleading. I'm also going to go grab some fuel to be sure. My trip meter has ~90 miles since I last filled it, so I would have guessed to have a few more miles at least before hitting that point, but that could be all it is...this symptom does seem easily fuel-related.
The electrical is also a potential issue, since previous owners did add aftermarket lights, etc. I'm just going to trace everything and make sure I can rule that out as a possibility too. I didn't even know there was a clutch safety switch. :) I guess I'll probably have to come across that switch at some point tomorrow though.
Thanks for the info...lots of that helps! Testing procedures like that are the things I need to learn most.
Just verified... Both the tank petcock and the main petcock are labeled. There is no reason for anyone to mix this up...just look at the labels. I was "blindly following orders" from the Haynes manual and it wasn't clear enough, so I pulled my info from the Suzuki parts diagram, thinking that had to be right... It would have been far better to just look where the hoses connect.
My sputtering felt like it easily could have been gas, and this probably solidifies that as the issue I had yesterday.
I noticed this as I was gearing up to check over the electrical...still going to do that to be sure of the other questionables (like my neutral switch/light situation and the previous owners' work), but with finding that clutch adjuster totally out of place and the reversed fuel hoses... I may have a perfectly fine bike when I'm through today!
I'll report back either way and let you guys know. Either way, thanks again everyone for the help/suggestions/ideas/etc. I think this problem forced me to essentially take a crash course on nearly every major system on the bike, and I'm far more confident in tackling stuff like this. You guys kick ass. :)
Another update.
The electrical seems to check out. The neutral light issue was the bulb after all. Everything else seems to be working properly.
Reversing my fuel hoses (and adding fuel to the tank, since reversed fuel hoses result in "prematurely" empty tanks) completely resolved my issue of being stranded the other day...it was just gas after all, and my attempts at push starting it while limping it home probably let just enough fuel trickle into the lines so that I could start it and go for just a little bit before it would die again.
My clutch does not seem to be coming loose anymore, and the operation stays consistent throughout my ride now. I don't feel any obvious slipping, and engine breaking works wonderfully.
The good news about the above, is that when I was running out of gas, it immediately felt to me like running out of gas might be my issue. The bad news, is that is definitely not the same issue that it all started with, and it's absolutely not the problem I'm still having. ;)
Now, it feels like taking off from first is perhaps slightly more rough than it should be, until the bike makes it up to around 4k RPMs. If I'm really easy on the clutch, it won't chug on take-off, but there's not much power until the 4k RPM mark or so. After that point, it seems to have decent power for all of 2nd and 3rd gear. 4th-6th are fine so long as my speed is below ~60mph.
On the freeway, I can get up to ~80mph in 3rd gear, but the moment I shift to 4th, it looses power and slowly decelerates (even with full throttle) until it drops down to about 60-65mph...all of this on level ground. I can maintain speed and accelerate past traffic (and even slowly accelerate up minor hills) in 3rd, but it takes some time...and once I go above 3rd gear it's like the engine simply struggles to continue to output.
When I am riding at full throttle, I can slowly roll the throttle back until about 1/2 throttle before the engine starts to sound different and the bike actually starts to slow down. This effect is extremely obvious in 4th-6th at freeway speeds.
For these symptoms, the Haynes manual seems to point primarily at the carburetors...so I'll probably turn today into another carb day. Going to check the slides, blow out the passages with compressed air, remove the hoses and blow all of them out as well, check float height, etc.
Here's the big question now... How fast should the bike accelerate, and what should my effective top speeds be in various conditions?
My major comparison is with my Toyota Corolla...and right now, I seem to be able to accelerate at about the same effective speed from 0-50 as my Corolla. I would assume that the bike should be a bit snappier than my car, but that isn't the case. If I were to drag race myself, side by side, I would probably still win in my Corolla though... I'm really not certain, but this seems wrong. Perhaps not nearly as wrong as I might think, but it seems like the GS500 should be able to perform better than that (I feel like it did when I first got it, though I didn't really truly pay quite as much attention as now).
Top speeds?
Ok, go read my message elsewhere in this thread about RPMs http://gstwins.com/gsboard/index.php?topic=61400.msg714164#msg714164
If your RPMs can match those you have something to work with. If not, there is something to work On. Double check then get back to us with the results.
Michael
Mister:
My RPMs seem to be in-line with that. I can't check 6th gear for certain though, since I can't maintain speed at that gear, but for 4th, I can say that I match.
It really feels like the engine just stops delivering any more power, and there is a shift in tone at the same time my throttle stops being effective (this is the sound that makes me feel like it could possibly be the air filter or something). It's almost as if the engine knew it needed to deliver more, but it simply couldn't do any better than it was at. The thing that draws me to the carburetors though is that it seems linked to throttle position rather than road speed.
Before taking the carbs off my bike, I checked the float height with clear tube method...and I found that only the carb on the right side was off...fuel is coming up above the gasket (about 1/4" or maybe a little less). Could something like this be the cause of my issues? What would happen if just one float were off by about that much?
I also noticed this time that a vacuum seal is cracked and should probably be replaced. If we add this into the mix with the find above, would that all add up to the issue?
Now, the big one this time... How do I adjust the float height correctly on a 2005 model? My carburetor is simply different than the one in the Haynes manual, and while I think I could probably figure something out, I'd rather be certain I was doing it the right way. Can anyone point me to how to adjust the height on a 2005 model specifically?
Oh, and one of my throttle cables stabbed my finger when I took them off of the carbs. I'm going to need to replace that thing for sure too. It's starting to fray somewhat near the ball-end that hooks onto the carbs. Significant, but probably not something that I would have really noticed until it would seem to stretch, right?
Hopefully the local shop has something that will fit my bike for this one...seems like it would probably be rather generic though.
If the carb height is too high, you'll get fuel draining into the crankcase, which is never good. Surely a vacuum leak could be contributing to your issues.
The Haynes manual I have includes pictures of the early model carbs and the late model carbs at the beginning of the chapter. Though the float height adjustment process is illustrated using pictures of the old carbs, the process is the same for the newer kind.
I just wanted to be sure I was bending the right part. The tab on my floats looks very different from what's pictured. I think I've got that figured out. We'll see in a little bit...gonna run and get some parts.
You mention little power in first gear till 4k rpms... I don't think that's out of the norm for these bikes. In most gears, under 3.5 k rpms and you will definitely feel the engine chugging with no immediate acceleration when you put on the throttle. It's harder on the bike to do that, so try to get the revs up before really loading any decent amount of throttle... A quick downshift may help if you are in a higher gear.
-Bboy
BockinBboy:
Good to know. I figured it probably was, but I just wanted to be sure that was normal for certain. I've been noticing that my best power range is between around 6k RPMs and 8.5k RPMs. I try to set myself in a gear so that I am sitting around 6k RPMs as I cruise along, so I can quickly get some speed if needed. For my speed tests, I was still finding power at high speed when I dropped to 3rd, but 4th and above just couldn't cut it. Even at full throttle in 4th gear...so if I change to 4th at 80mph, I would start to slow down as if I had let off the throttle a bit. It would rather quickly (well within a 1/4 of a mile) slow down to around 65, but I could drop into 3rd and accelerate again.
Hopefully that float on the right carb being adjusted to the right height and replacing that vacuum cap will make all the difference with my throttle/power. It's just too bad I had to deem it unfit to ride until a new throttle cable arrives though.
Well, after a nice long wait on a back ordered throttle cable, I was able to get everything back together for a test drive again.
Here's what I did to it this round:
- I put a brand new air filter in it.
- I adjusted the float height on the carbs after noticing one side off a bit.
- I re-capped a vacuum seal on the carburetor since the rubber was cracked all of the way through.
After my test drive, I have good news and bad news:
- The good news is that starting out of first seems a bit smoother than it was before, but it's still probably not at 100% yet.
- The bad news is that my top speed/throttle issue hasn't gone away.....though usually only seen in higher gears, if I accelerate quickly out of first it can suffer from the throttle issue too.
When in 3rd or greater is when I notice the 1/2 throttle issue the most; between full throttle and 1/2 seems to be no change in power. It also still seems to have the same "air sucking" sound when I apply more than 1/2 throttle... It sounds as if it were trying to pull more air through and it wasn't getting through for some reason...something like that (it really reminds me of what my car sounds like when its air filter gets pretty dirty). 4th gear has nearly 0 acceleration, 5th gear can simply maintain speeds lower than ~60-65mph, and I haven't even really bothered with 6th, assuming it would be the same too.
I'm out of ideas again for the moment...
have you checked to see if the carburetor butterflys are opening fully and in unision .You will need to remove slides to see, unless you have carbs removed from there boots and can see and operate the throttle.
Sorry Nicro, I can't remember what you have / have not done entirely. But it's sounding like a high rpm fuel delivery issue. Float bowl level, constricting petcock(s), clogged gas cap vent, clogged carb vents, or a dirty inline fuel filter (on tank petcock or aftermarket).
Alright...so, I eventually gave in and took my bike to the shop. After all of the waiting, I'm finally back in action using my GS as a daily driver. :)
It turns out, the guy I bought the bike from had the wrong size pilot and main gets in the carbs. I'm not sure if it was working great when I got it just on chance, or if I just hadn't driven it hard enough to really know...but apparently when I started fixing things, it looks like I might have "fixed" enough that it threw the whole system out of whack. The jets that were on the bike were making the mix too rich, and there was just no way around it I guess.
I just wanted to update the thread with some closure, and say thanks again for all of the help from everyone. I learned plenty about my bike in the process, and now my daily commute is much more entertaining. Hopefully this beast of a thread can still help others that wander through on a search!
Quote from: NicroHobak on October 30, 2012, 01:04:22 PM
Alright...so, I eventually gave in and took my bike to the shop. After all of the waiting, I'm finally back in action using my GS as a daily driver. :)
It turns out, the guy I bought the bike from had the wrong size pilot and main gets in the carbs.
Possibly it was "right" while he (or previous owner!) rode it, but bike was "returned to stock config" for the sale... except for the jets :-/
Quote from: Phil B on October 30, 2012, 02:52:58 PM
Possibly it was "right" while he (or previous owner!) rode it, but bike was "returned to stock config" for the sale... except for the jets :-/
Very true...bad word choice on my part. ;)
It was actually "right" when I first had it, and that's why I didn't think I would need to do anything with jets except clean them, etc. I was kinda figuring that I simply had one problem, then I started to "fix" another and threw the whole thing out of whack because I probably readjusted something to stock settings before I actually fixed the original problem. The net result would be similar to what I experienced, I think.