Hey, from Southern California (oh... and help, I feel like I'm riding a bull)

[quiktaco]

(sorry, had accidentally posted this in the meet and greet section)

Hey everyone, just saying hi.  Just bought my 1996 GS500E about 2 weeks ago, took the MSF coarse 3 weeks ago, got my Motorcycle license 3 days ago, and now i need your help.  I've searched and have sorta found a similar problem, but no solutions.

ok, so my problem is... 

Background - got bike 2 weeks ago.  Test drove it (a little bit), and it drove fine.  Started easy, and there was no problems with it.  And because I didn't have my license yet, the guy even drove it to my house.  Now i've been riding it a little here and there in a residential track to get used to it and practice before I get out on the main roads.  For the most part it's been fine, but it's been really hard to get started.  would have to crank it about 10 times for at about 3 second intervals before it would finally turn over.  Then I'd let it warm up for about 5 minutes or so, and it would be fine, and drive fine.  Then about 3 or 4 days ago, I pulled the plugs to see if they were fouled to see if that's why it was hard to start.  They were...both of them (carbon fouled).  I'm guessing that the PO either road it with the choke on, has the mixture screws too rich, or the air filter is clogged.  To my knowledge it is completely stock, but the mixture screws on both carbs do not have the brass cover on them.  Let me know if my assumptions are totally off.  I don't have any experience working on bikes, but I do know my way around a car.  There is a little over 40k on the bike, so i'm pretty sure it hasn't sat for any of it's life, and the PO claimed that all the regular maintenance was done.

Ok, so the bigger problem beyond fouling plugs...I replaced the plugs with normal temperature champions, just to see if that would fix anything.  It started up great with one crank of the starter!  But then, I let it warm up for a few minutes and took it for a test ride, and it bucked, lurched, and had major power loss (I turned the throttle traveling about 10mph and it didn't do anything, but blip a little, then all of the sudden there would be a major power increase).  None of these problems occurred with the old plugs.  I think it may have needed to warm up a bit more, but I was able to take the choke off and it idled perfectly, so I figured it would be ready.  Once i got to higher RPM's, the problem mostly went away, but I could still feel it missing a little bit. 

I know that something isn't right.  Please help me with what it could be.  What is the list of stuff that I should check?  float levels, air filter, synced carbs, old gas, what?  Please tell me the easiest to the hardest to check, so that i can narrow down the problem with the easier things first.

[flyingmachine]

I'm in Fullerton, had the exact same problem.  It sorta went away after I poured some seafoam in the tank and kept the petcock on prime.  So either dirty carb or vac leak causing bad fuel delivery for me.  Good luck.

[quiktaco]

cool, thanks.  I've used Seafoam in my truck, and it was great.  How much did you pour in the tank, and how long did it take to fix the problem.  I'm guessing the problem was a little varnished gas in the carbs?

Did you have a vacuum leak?  What would be a fix for that, and where was the leak at?

[quiktaco]

anyone else with any possibilities to what it might be?  I really don't feel safe with it bucking and hesitating the way it was.  It would nearly die when I came off a start, and there would be almost no power for a good 5 seconds until it suddenly hit with power.  Pulling out into traffic is not possible right now.  Any other advice/tips/experience is greatly appreciated.

[scottpA_GS]

Seems to be a common idea on here that Champion plugs are crap in the GS... First off get some NKG's or something other than Champion 

If you are somewhat mechanicly inclined (sounds like you are) it cant hurt to pull the carbs and give a quick cleaning... the seafoam is a good idea but just the easy route and it wont give you a proper cleaning.

If your brass covers are off the mixture screws than someone messed w/ them. your best bet is to get better plugs and try and clean the carbs. that should solve your problem.

there is a good post in the DIY section on the main page for carb cleaning

[scottpA_GS]

After searching I see that some reccomend Champion 809's ? But I am certain that some on the board say that Champion plugs do not do well in the GS..

Still a good carb cleaining is in order 

[flyingmachine]

can't remember the exact amount of seafoam, but it wasn't much.  I found the leak when I sprayed carb cleaner here and there while the bike was ideling and just listened to changes in the rpm.  I think the main culprit was the vacuum lost at the prime/on/off selector.  The problem pretty much went away when I leave it in prime.  Seems it's a common thing to do, search on a write up on this board for a proper prime bypass. 

Just remembered, the previous owner also had all the CA regulation hoses for the tank vapor recycling removed, leaving a hole where it goes into the carb.  I think that contributed to my bike running lean.  I put them back in myself, but I was told just plugging the hole would be ok also. 

[quiktaco]

thanks for the replies.  I'll get some better plugs, these champions were all I could find on Sunday, cause the other places around here were all closed.  They were cheap, so I thought I'd give them a try.  I'll probably run the NGK iridium's once I find out why they are fouling.

I'll try the seafoam and see if that helps any, and if it does, then I'll pull the carbs and clean them up.  If it doesn't, then I'll check for a vacuum leak.

Do you guys think that it's not getting enough fuel?  (from the replies of gunked carbs, or vacuum leak)

From what the old plugs looked like, it looks like it's running rich, but I guess they could have been fouled if the PO road with the choke on.  So maybe it's running rich to foul the plugs when the choke is on, then running lean during normal driving when the choke is off, because of either a vacuum leak, or the carbs are gunked.

Looks like I've got a few things to check.  Thanks for all the replies

[pantablo]

make sure it IS warmed up. even if it idles fine it could be cold on throttle. these bikes are cold blooded and require 5-10 minutes to warm up, even here in CA and even then you have to baby the throttle to keep it stalling. That assumes stock jetting, which it sounds like you may not have if the brass plugs are gone. Just a thought.

[ohgood]

clean the air filter if it's a k&n. replace it if it's not.

is the exhaust stock ?

replace the fuel lines, dump seafoam, change the oil, plugs, and do all the stuff that handbook recommends. 

how's your chain look by the way ?

also - you know the gs doesn't like really low revs right ? keep the revs above 2500 -3000 rpm and it should run smoothly to 9,000. it's go ridable torque, but only 25 ft lbs of it

[quiktaco]

   So, I topped off the oil, cleaned up the old NGK plugs a little and put them back in, and put some Seafoam in the tank.  It had a little trouble starting like it used to, but was a little easier.  I let it warm up for about 4-5 minutes, then took off.  I had a little shake and studder, but it was so much better.  Maybe could have used a minute or two more to warm up, but this was great compared to a couple days ago.  toward the end of the ride, it also started to seem a little smoother and easier to control.  The seafoam must have started to get circulated.  I also tried keeping it in higher RPM's like suggested.  The bike sure does seem to like it a whole lot better.  I keep forgetting that it Redlines at 11 instead of 5.5 like my truck.  I've been shifting at around 5-6, and it didn't like dropping to 3ish before.  This time I would let it get to around 7ish before shifting.  Much smoother overall.  Thanks everyone for all the help and info.  I'll still be doing a bunch of the checks and things to make sure everything is in order, but at least it's rideable now. 

Oh, and (remember I am just learning) my left grip muscles are killing me from squeezing the clutch!  I love it!

And btw, this forum is great!  I've been on too many where people only trash talk, and you can't get a simple question answered.

[nikux]

I had similar problems at low rpm, for me the problem went away with cleaning the carbs and rejetting the pilots to a 40.

[quiktaco]

Ok, so the whole bucking thing is pretty much gone.  That Seafoam is amazing stuff.  So now I've got another problem.  I got off work early, so I thought I'd go for a ride (just got back in).  Everything was great.  Started okay, drove great, but then about 20 minutes into the ride, the idle just wouldn't go down.  It stayed up around 3-3.5k whenever the clutch was pulled in.  Even at a complete stop when it should be at 1200, it was at 3k.  Once I would let out the clutch to take off into first, it would immediatly drop to where it was supposed to be.  Until the 20 or so minutes in, the idle would be around 1200, then all of the sudden, I come to a stop, and it's really high, and it stayed that way till I got back home.  Is this just that the idle needs to be adjusted or is this a sign of something, like running lean/running rich/unsynced carbs?  Please help!

[pantablo]

THAT is a sign of a lean fuelling condition. usually bikes that still have stock jetting do that naturally.  They come lean from the factory to meet emissions requirements.

I never rejetted my bike. All I did was lower the idle speed to around 1800 when warm, just enough so it wouldnt die when cold/warming up and just lived with it. If yours is still stock this would be it. if you're certain its been rejetted then could be an air leak somewhere (check the carb/head rubber boots).

[quiktaco]

Thank you so much pantablo, I'm pretty sure that it is stock (not positive though).  I've been planning to get the lunchbox K&N and rejet to counter that, so the problem should be fixed then.  I'll just have to deaol with it until then. Thank you.  I was hoping that it was a normal thing like that and nothing going wrong. 

[kml.krk]

I also had the problem with too high idle RPMs. when the bike was relatively cold everything was fine (idle around 1200) but when it got hot idle was at 2.5-3.5K it was annoying cause I had to use brakes much more to slow down or to come to a complete stop.
I just set the idle to around 1400 rpms at fully warmed up engine so it doesn't stall when cold and is still fine when warmed up.
cheers
KaMeL

[flyingmachine]

quicktaco, good to hear your bike is ridable now  .  have you tried the prime idea?  My high idle (stuck sometimes) went away after I use prime.  I'm not having any problem at speed, some suggested running in prime will get you problems at high rpm/speed, but I'll get a after market petcock just in case.

[kml.krk]

what about the mileage when using the prime? I read somewhere on this forum that your bike will do much worse mileage on prime than on regular petcock settings (ON)
is it true?

KaMeL

[flyingmachine]

I know my mileage isn't the best, around 40-45 mpg only running on prime.

[slowinthestraights]

what about the mileage when using the prime? I read somewhere on this forum that your bike will do much worse mileage on prime than on regular petcock settings (ON)
is it true?

KaMeL

No, prime just means that it is like a standard fuel valve, and in the ON position. If you get worse MPG, something is wrong.