Hello All: I don't use my 2001 GS500 much during the winter. It stays in the garage, with fuel conditioner added to keep the gas from degenerating, with a short ride around the neighborhood about once a month to keep it lubed. It is a new looking machine with only about 3000 miles on the clock.
Yesterday I took it for a 20 mile ride, and while it starts and idles just fine, there was no power in gear. Top speed about 55mph and a long time to get there. Several times it seemed to regain full power for few seconds, as if a fuel blockage had cleared, then fade back out. I stopped enroute to top off the gas from the two gallons used during the winter, and to add some carb cleaner to the tank. As far as I could tell, the carb cleaner after about 15 miles of riding had no effect.
I would appreciate any advice on the most likely causes and cures. I'm not much of a mechanic, but in this case I'm thinking of learning to clean my own carbs, since it is an expensive operation. When I bought the bike several years ago it had been sitting unused in a garage for 10 years, and would barely idle. A professional carb clean and tune up got it running nicely then and since, but it is sure a hit on the wallet to have that done again for the few miles I am putting on this bike.
Thanks, MaxD
definetly fuel blockage (in my experience), taking carbs apart aint that big of a deal, probably mid/main jet blocked, one hour fix from an unexperienced mechanic 😁
OK, thanks. Man, reading back over that recent carb or ignition problem thread ("Feels like ignition" with engine losing power at around 9k rpm) between you, Mr. 72, and Buddha, I am amazed at how tricky these carb problems seem to be for a supposedly easy to maintain basic bike. Long term experimenting with different needles, etc, lots of uncertainty and theorizing, trying everything that can be thought of. Seems like 72 had to put in quite a few hours before he got that fixed.
...MaxD
Quote from: MaxD on April 28, 2020, 11:37:34 AM
Seems like 72 had to put in quite a few hours before he got that fixed.
Well that's an understatement :)
And it applies to the entire bike, not just the carbs! :)
Josh, I like this bike and the idea of getting good on the maintenance, such as learning to do my own carb cleaning/adjusting and setting my own valve clearances. I'd be proud of myself if I had half the skills you guys have in maintaining the bike. But, if the most riding fun at the lowest total cost of ownership is the goal, then just reading about the extreme hoops you and others are having to jump through with those finicky carbs (which seem to get fouled for no good reason) and the valuable time that must take has me comparing the GS500 unfavorably against the modern fuel injected CB500X with a 16,000 mile valve adjust interval. I guess an owner staying with the GS500 when that lower maintenance, higher performing competition is available is doing so because they consider the extra wrenching to be part of the enjoyment.
^^ In my experience of owning multiple GS500s the newer 2001-2002+ carbs were the best because the floats don't drift.
If you don't mess with your carbs & don't let the bike sit, the carbs won't mess with you :D
Quote from: HPP8140 on April 29, 2020, 07:45:48 AM
^^ In my experience of owning multiple GS500s the newer 2001-2002+ carbs were the best because the floats don't drift.
If you don't mess with your carbs & don't let the bike sit, the carbs won't mess with you :D
Correct - the 04+ ones also don't drift, but them carbs have a lot more complicated crap.
However, I am having issues with 01-02 carbs on my 95 and the 89-00 ones do better but still issues. It may be unrelated to carbs - more like petcock issues.
Cool.
Buddha.
Quote from: MaxD on April 28, 2020, 06:02:39 PM
if the most riding fun at the lowest total cost of ownership is the goal, then just reading about the extreme hoops you and others are having to jump through with those finicky carbs (which seem to get fouled for no good reason) and the valuable time that must take has me comparing the GS500 unfavorably against the modern fuel injected CB500X with a 16,000 mile valve adjust interval.
Well, the GS500 is really easy to service, at least the '89-00 era bikes. The later models get more parts, more complicated carbs, etc. But it's still nothing compared to a modern CB500X.
The nice thing about being so simple is you can tinker with it and you have a pretty high probability of success. You also have a high probability of future issues. So you really have to be into working on motorcycles and the quirks, occasional unreliability, old parts, all that, has to be part of the charm for you.
The truth is, there came a time when my GS was having too high a repair:ride ratio for me and I didn't trust it for long trips or daily transportation, so I bought an additional bike. My other bike has a near zero repair:ride ratio since it never breaks and never requires any repair or adjustment ... just maintenance of wear items like brake pads, tires and oil changes. And the fact is I ride it so much, I have worn out these wear items. This allows me to treat the GS like a classic bike, which it really is. It requires too frequent repairs but if you ride it very rarely then those repairs also come rarely and it's tolerable.
I would go crazy if I was still having to rely on my 28 year old GS500 for an everyday bike. It's just not up to the task of a daily rider unless you employ classic British bike style maintenance and repair schedule. I would guess a mid-late '00s bike would be much more dependable day by day, but maybe less interesting or fun to work on.
Josh, I appreciate you taking the time to give such a thoughtful and complete response.
I bought this GS500 because I stumbled on a good deal for it after I gave my daily driver Mazda Miata to my son, and the only car I had left was a Jeep Wrangler getting 16MPG. I thought the GS500 would be fun to ride and let me get some good mileage to work on nice weather days. All the reports on it I read touted its excellent reliability and bulletproof nature. You get a lot of statements along the lines of how it outperforms the similar old British twins, but at much higher reliability, and the engine "just runs forever". Despite its low cost, it seemed to be the peak of the classic air cooled parallel twin, carburetor fueled architecture. So, I was happy to get a new looking GS500 garage queen with 1300 miles on it for $2200.
And, it has lived up to that, EXCEPT for those carburetors. I'm as irritated at those things as WWII Battle of Britain Spitfire pilots were every time their engine quit in a dogfight under negative g, while the Me 109 on their tail kept running fine since it was fuel injected. If I ever do get another bike, it is for sure going to be fuel injected, if it runs gas at all. There is a new generation of electric bikes already here, where about all you have to do is change the tires. It does not have the classic charm of a throaty gas engine, but you turn it on and it goes.
In the mean time, I'll try to figure out working on those frigging carbs, and see if I can into the spirit of being my own mechanic.
...MaxD (aka Farron)
A GS500 can be reliable but GS500's like to be ridden and wrenched on (maintenance, not modifications). If you use them as a commuter bike, they never need anything other than normal consumables and semi-frequent valve clearance checks. The maintenance intervals are frequent but the tasks themselves are not too difficult.
The farther you get away from stock, the more trouble the bike will give you. The less you ride it, the more trouble the bike will give you. Most issues you see on this forum are people trying to bring bikes back to life that have sat for months or years without use or proper storage prep or people who have gotten too far into the deep end of modifications.
If your 2001 GS 500 really has 1300 miles on it, that's an astonishing 68 miles per year. More likely it ran 1300 miles in one year and then sat for 18 years. There is nothing worse than that for a carbureted bike. I am surprised it runs at all without a full carb rebuild.
Ride the GS500 whenever there isn't snow or ice on the ground. That is the correct maintenance schedule.
GSJack put ~100,000 miles on multiple GS500s and never did anything but adding a few comfort/convenience mods and follow the Suzuki maintenance intervals. He never adjusted or cleaned the carbs afaik.
I have almost 45,000 miles on my '06 GS500. I have never cleaned the carbs. Only recently did I go through them because the rubber parts were now 15 years old. I expect I'll get another 45,000 out of the GS and then throw it in the trash.
Other than starter clutch bolts backing out and a faulty ignition pickup, I have never had a problem with a GS500 that wasn't somehow my fault. I think the GS500 hits the perfect balance of maintenance to reliability. Yes, you have to work on it but the procedures are easy to learn and you get a routine going. My first valve check was scary weekend but now I can do it in an hour or two. I have sold other bikes that required 0 maintenance because I never felt like I was one with the bike. The GS500 needs you and you need it. If you don't want that sort of connection with a machine, a modern Honda or electric is the way to go. My wife's Honda 2018 CTX700N DCT has 8,500 mile oil change intervals. It drives me nuts having nothing to do on that bike but check tire pressure. But for my wife, a motorcycle is merely a convenient form of transportation. If she had to ride a bike like the GS500 with a manual transmission, 3,000 miles oil change intervals and 4,000 miles recommended valve check intervals (why are they not the same interval Suzuki?!?) she would have never taken up riding in the first place.
I had a Vstrom 1000 that wanted to go 100 mph everywhere and never needed anything, even if you rode it hard and put it away wet. I heard the Vstrom 650s and SV650's are the same way; bikes that fit into the "appliance" category. The GS500 will never be that kind of bike. The GS500 requires that its human companion is also reliable...ready to go with the helmet in one hand and a repair manual in the other.
Another thoughtful response, so thanks.
Looking at my maintenance log, the bike actually had 1600 miles on it when I bought it. The gas in the tank was probably years old. I could barely coax it to the shop, but they got it running perfectly by de-rusting the tank and cleaning the carbs. I've since put only about 1500 more miles on it. It seems my mistake is thinking that if I keep preservative in the gas and ride it 300-500 miles per year that should keep those carbs sufficiently clean. The preservative is supposed to keep the gas good for a year or two, so I assumed it would last through the winter with just a few rides. But, unless the tank has gotten rusty again and fouled the carbs though no fault of their own, it apparently needs more than about one short ride per month through the winter.
You guys are giving me clear warning to ride often to keep the carbs clear, but the authors of my motorcycle books are not alert to mention that.
From "The Complete Motorcycle Book", 1995 edition, page 118 on the GS450/500: "It is easy to learn on and easy to maintain. The long lasting engine simply runs forever". No mention of the requirement to ride often to keep the carbs clear, either there or in the pages devoted to carburetion.
"The Essential Guide to Motorcycle Maintenance", 2004, pages 60-69 on carburetor maintenance: Nope, not a word on the need to ride often.
OK, lesson learned the hard way...
I dunno when it was - So I'll guess pre 1996 - gas will keep the tank from rusting.
Now with the miracles of oxygenated and alcohol mixed gas - it will rust - just from the gas.
You really want to put oil in it and swirl it every other week or so to keep it from rusting and a GS tank keeps about .7 quart when you have tried to drain it. So you're gonna have to keep the tank off the bike and swirled in oil. Gas aint gonna save you.
You can tank EPA for that - and there aint no typo in that sentence.
Cool.
Srinath.
Bluesmudge should know a DL650 of the original generation likes to be helped. Not much but some. Aside from water cooling and FI, it seems to be made of the same stuff as a GS 500.
When you have time to look, things need attention.
I do agree with riding a bike as a best practice while owning it.
Quote from: MaxD on April 30, 2020, 05:12:48 PM
From "The Complete Motorcycle Book", 1995 edition, page 118 on the GS450/500: "It is easy to learn on and easy to maintain. The long lasting engine simply runs forever".
I think they mean long lasting while riding it...not while siting. Any motorcycle can sit.
Those books probably don't mention dry-rot in the section about tires. Thats because they figure in the 10 years it takes for the tires to rot you would have put at least enough miles on the bike to need fresh tires. Most maintenance is to account for changes caused by use...not lack of use.
Buddha is correct, its the E10 gas that has caused a lot of these issues. Those books you have were written before ethanol was much of an issue.
You used to be able to let a bike sit for a year no problem with 100% gas. Then around 2002 E10 become the standard. Carburetors do not like E10, especially when the gas is old. The ethanol is hydrophilic, eats at the rubber lines and seals worse than gasoline, and makes the engine run leaner. Steel gas tanks don't like it either. I don't winterize my bikes, so if I'm not riding for awhile I try to keep the tank full and then run at least a tank of fuel through each month to get the water out of the tank.
I recently went through a Kawasaki carburetor that had been stored for 5 years without draining the float bowls. Everything was varnished solid like glue. Had to replace every part of the carb that moved or had an orifice. The tank had to be de-rusted. Putting 0 miles on that bike for 5 years did more damage than riding it for 20,000 miles.
You get a little bit more leeway with fuel injection, but even then no bike (no vehicle for that matter) likes to only be ridden a few hundred miles per year. 500 miles per year is only 3 tanks of gas per year. That means that every time you go for a ride you will have gas that is many months old, constantly pushing your luck.
A lot of parts of the bike need maintenance based on time. You end up having to replace tires, batteries, brake fluid, and oil without the benefit of putting the miles on the bike. You are just keeping the machine safe to ride as Father Time works his magic on rubber parts, battery cells, and hydrophilic liquids. If that is how you are going to treat the machine, treat it like a rarely used weed wacker or lawn mower and find a station that sells 100% gasoline to run in it. You will have far fewer problems long term:
https://www.pure-gas.org (https://www.pure-gas.org)
For your current situation, you could see if riding it more with a little bit of seafoam or gumout eventually solves the problem. Completely draining the tank (not really possible on a GS500 tank but you can get close) and filling completely with fresh gas might tell you a lot.
Btw, thanks for this thread. Its reminding me I need to take some of my lesser used motorcycles out for a long ride.
Yes, that is irritating that we can't easily get gas without that water trapping alcohol. What we need for that is an intentional low point drain to get the water out, such as all light aircraft have. You drain out a few ounces of gas before every flight. The reason we need this even more with alcohol blended fuel is described at https://www.popularmechanics.com/cars/hybrid-electric/a6244/e15-gasoline-damage-engine/
Not to criticize the GS500, but my guess would be that since the designers are generally competent and paying attention, the more modern bikes should be designed to better cope with the alcohol in the gas.
Awesome thread. I don't have much to add except that in 8 years of owning my '98 (22k miles on the odo) I've never had to mess with my carbs (thank God).
I ride year 'round... but don't put many miles on. Heck my "commute" to work is 2.4 miles. There are times in the winter where my bike will have to sit, due to ice and snow, for 3, 4, 5+ weeks at a time... and I've never had any problems (starting it up or riding it).
I've run some Seafoam through from time to time... and when it's parked at home, it's in my house/heated garage. I suppose that would make a difference (as opposed to a bike stored in the cold and/or outside).
I'm amazed at people who disdainfully refer to the GS500 as a learner's bike, I have recently moved to a location with possibly the best scenic motorcycle rides anywhere on Earth, it is perky and a lot of fun to ride with plenty of acceleration for a 60kg rider, and only a bit sluggish when accelerating with a 65kg passenger. I've only ever needed to do the most basic maintenance, and apart from having to put a new set of carbs on due to a rare problem where the press fit slide guide came loose, I have never done anything elaborate, I bench set the carb balance with my eyeballs, and never touched the float. Maybe put a slightly larger jet and that's it. At 70k kms it uses almost no oil, maybe a cup over 6k kms and even the slight oil seepage around the bottom of the cylinder head, became completely dry after a half a dozen back offs and retorques, during the service cycle. Mind you I'm usually driving around 5 or 6k revs, but I do give her a bit of a fang now and then. I did ride 200kms in a light rain at 8k revs doing 100mph because I was pi55ed off one night but that's about it. I probably shouldn't be saying this because the last time I opined how I good it is, was when the press fit part cacked out
Quote from: user11235813 on May 01, 2020, 03:10:09 AM
apart from having to put a new set of carbs on due to a rare problem where the press fit slide guide came loose, I have never done anything elaborate, I bench set the carb balance with my eyeballs, and never touched the float. Maybe put a slightly larger jet and that's it. At 70k kms it uses almost no oil, maybe a cup over 6k kms and even the slight oil seepage around the bottom of the cylinder head, became completely dry after a half a dozen back offs and retorques, during the service cycle.
I like the GS500 a lot. Its one of the most well-rounded and high value motorcycles ever. But the simple fact that an owner has to be able to understand what you are talking about there, shows its not for everyone. Modern motorcycles don't need that level of mechanical knowledge.
I agree motorcycles designed after E10 became standard are better suited to the fuel. But many brand new 2020 bikes sold (especially by Suzuki) are 20 year old designs that will be just as disinclined to sit as the GS500. Looking at you, XR650L, DR650, DRZ400, DR200, TW200, Ural. A new rider walking one of those off the showroom floor should know they don't like to sit for 6 months+ without all the gas removed from the tank and carb.
When I was new to motorcycling and had 0 mechanical knowledge in 2008 and purchased a 2006 GS500 I would have assumed it was designed to handle the fuel of the time. It wasn't true then and its even less true today.
Thanks to this thread as a reminder, I ran my recently restored 2001 Kawasaki Super Sherpa for 50 miles yesterday to finish off its little 1.7 gallon tank of gas and fill it up fresh. I had never had it on the freeway since getting it running but the little carbureted 250 single got me up to 84 mph! As much as I love having multiple motorcycles, keeping track of all the maintenance can be a drag. Not riding much during the global pandemic also isn't helping either.
Quote from: MaxD on April 29, 2020, 09:18:41 PM
I bought this GS500 because I stumbled on a good deal for it after I gave my daily driver Mazda Miata to my son, and the only car I had left was a Jeep Wrangler getting 16MPG.
FWIW this is very familiar. I bought a 2000 Miata new in 2000, drove it for 14 years before I tore it all the way down for a light restoration, rebuilt/built engine, paint, upholstery, whole deal, and then it was totaled in 2015. I bought a new Wrangler Unlimited and that's my four-wheeler now. Then I bought the GS500, and then the Triumph. But my Miata never got very good gas mileage, upper 20s, I guess because I drove it with the top down nearly 100% of the time and touched the rev limiter often. The Jeep gets nearly 18-19 on average even with 33" AT tires, heavy bumpers, a 2" lift and a 9k winch. But my GS gets low 50s. And I work from home so I only put about 3-4K/year on my Jeep and about 6K/yr on my bikes.
So, using ethanol-free fuel will greatly improve the length of time you can go without having to tinker with the carbs.
And remember when those old books were written, 20K before needing a top end rebuild was pretty ordinary. These days with water cooled motorcycles, they can go a lot longer without needing major service, but by comparison a GS really is an old school bike. It's air cooled and a lot of the wear you get on it has to do with how well you treat it. Mine had bent valves when I got it due to carbon buildup on the back of the valves. IDK how to avoid that but neither did the previous owners.
The biggest problem with a lot of these old GS500s is that they are mostly by now being sold off by the latest of a series of "first time" motorcycle owners who buy this line that you should buy a GS500 class bike, ride it for a year, lay it down and screw it up in a dozen ways, then sell it to someone else when they "outgrow it". And this happens over and over. So by the time you get it, it's probably had four or five owners who treated it like crap and didn't know what they were doing.
Quote from: mr72 on May 01, 2020, 12:45:39 PM
The biggest problem with a lot of these old GS500s is that they are mostly by now being sold off by the latest of a series of "first time" motorcycle owners who buy this line that you should buy a GS500 class bike, ride it for a year, lay it down and screw it up in a dozen ways, then sell it to someone else when they "outgrow it". And this happens over and over. So by the time you get it, it's probably had four or five owners who treated it like crap and didn't know what they were doing.
True for most GS500s but not the one discussed here. It had an owner that didn't do anything to it. Including riding it. Not sure which is worse, sitting for 20 years or being abused for 20 years. Probably the abuse. At least with the OP's bike you know why the problems exist and are less likely to find weird modifications.
Yeah you're right I posted too soon. Didn't finish my thought. Anyway all the rubber parts are still way past their use by date so I'd think a solid carb cleaning, all new o rings, new fuel and vacuum hoses would probably get it going just fine. That, and hope the cylinders are not scored from rust on the rings. And tires, but that's a different discussion.
I would absolutely buy a $2k 1500 mile GS500 garage queen.
I do think the abused history of these motorcycles is largely to blame for their bad reputation. Reminds me of how 240/260/280z were in the 80s and 90s. Tons of them with a string of adolescent owners in horrible states of disrepair and bad modification. But if GS500s are the same then the survivors like this are future classics.
Here is a quite good article on using E10 in motorcycles. It's from the UK since they are just now bringing E10 to Europe. Premium fuel there will be E5--too bad that is not the case in the United States.
https://www.bennetts.co.uk/bikesocial/news-and-views/news/2020/march/what-is-e10-fuel-and-is-it-safe
It point out in this article that E10 over 3 months old in motorcycles is a real problem. No mention is made of whether fuel preservative helps that.
From this article, we get this on Suzuki compatibility with E10.
"2002 Model Years and onwards - all motorcycles can use E10 with no problems.
1992-2001 Model Years – some models can use E10 fuels and some models cannot.
1991 Model Years and earlier – RON 98 (no bio-fuel content) must be used."
Checking the owner's manual on my 2001 GS500, it says E10 "may be used" (page 7). However, that can have a wide range of meanings, and here almost certainly means that the bike can run it without immediate engine damage, not that the fuel can sit in the carburetors for months without varnishing them up.
I have left the gas in my fuel injected 1993 Jeep Wrangler and my fuel injected 1996 Mazda Miata many times for more than 3 months, and never have detected any problem. It seems like a good bet that fuel injected bikes designed to run on E10 are going to have far fewer problems than older carbureted bikes.
But, we are GS500 owners who need to protect the carbs, and what we apparently need to do that is a quick convenient way to drain the gas out of the carbs when the bike sits, then reprime to start back up. If the fuel selector had an "Off" position and not just On, Prime, and Reserve, we could switch off and run the engine till it sucked the carbs dry. Similarly, if we had a convenient bottom drain in the tank, we could periodically drain an ounce of water contaminated fuel out in order to be even better protected (keep tank from rusting).
Are there any convenient fuel valves out there that can do one or both of those? To do everything would take a fuel selector with two inputs (main and reserve), two outputs (to carbs and to a drain line), and the five positions of On, Reserve, Prime, Off, and Drain. The Drain position would route from the reserve input (lowest point in the tank) to a drain line instead of to the carbs.
If not, the following would seem to achieve the same goals with the existing selector switch:
1. Plug the the reserve line to the fuel selector with a fuel impervious compound (or otherwise cap the reserve tank output and the reserve input to the fuel selector) to convert Reserve to Off, so that the carbs can get sucked out dry with a brief engine run anytime the bike is left sitting more than a week or so. That means giving up the reserve function as protection against running out of gas, which I would rather do than have fouled carbs. After such operation, the Prime function would have to be used to refill the carbs.
2. Install a "Y" branch valve in the fuel line with two selections (selectable but with one always on) where the single ended side goes to the existing fuel selector output, with one of the "Y" outputs going to the carbs and the other to a fuel drain line just long enough to hold a small container under when draining. When doing the drain operation, set the regular selector to "Prime" to let fuel flow freely, and the new valve to the side hooked to the drain line to drain a small amount of fuel. Then set the Y valve back to the other side to route fuel back to the carbs, and if priming is not needed set the regular selector back to On.
Is there any reason that would not work to allow both easy carb draining and easy fuel water draining?
Actually, just plugging the reserve line probably accomplishes 80% of the desired good, but I would like to slow down that tank rusting also. Beside draining water, it's an easy way to drain the whole tank if you want to winterize.
Well, my 1999 is an everyday rider, with minimal maintenance. Yes I cleaned the carbs when I first got it, but they've been faultless for 5 or so years.
People read some of the posts re: carb problems without realising that a lot of these problems are caused by misguided owners stuffing about trying to get more power or fitting pods etc.
"Just sayin'..."
Jools, I just can't take time to ride every day, and sometimes not even every week. But, I would like to keep the bike without that watery E10 gas rusting the tank and fouling the carbs. What do you think of the candidate fuel system mods mentioned above to manage the problem easily?
Quote from: Joolstacho on May 02, 2020, 06:28:07 PM
Well, my 1999 is an everyday rider, with minimal maintenance. Yes I cleaned the carbs when I first got it, but they've been faultless for 5 or so years.
People read some of the posts re: carb problems without realising that a lot of these problems are caused by misguided owners stuffing about trying to get more power or fitting pods etc.
"Just sayin'..."
This is beyond true. The number of weird BS I've pulled form these carbs would make your head spin.
Its got better after we published a lot of info - right around the time the old site was replaced by this one - In fact some of it I published on the mailing list in 98/99. My first tranch of 40 pilots were bought in Canada and sold on that mailing list to GS owners.
BTW I spoke to several Suzuki shops as well as dyno shops and independent shops back in the day - the first thing they said is - if the bike was giving startup and idle trouble and the owner found it early and brought it under warranty, they'd pull the air screw caps off and set them 3 out mostly free of charge but sometimes they'd charge them 50-100 for 1-2hr of the tech's time I guess.
The bike being out of warranty or the gas formulation changed or whatever that caused it to crap out - the bike got a DJ kit. Costs between 150-200 including the kit and a ride and tune.
Usually if someone had a bike that has been DJ kitted out, and the tune was done right and gas formulation hasn't changed since then - as long as they don't modify it further - it will simply work just fine as long as the float is set correct every other year or so.
But too many variables there - gas formulation, sale to new owners, parts of the kits getting lost to name a few.
In any case - my 89 must have been one of those random mod deals, the bike came to me with 42.5 pilots. Some genius took the carbs apart, found the air jets are 42.5 and put 42.5 pilots.
So if the bike you're now trying to fix has had anything like this happen in its past - you're gonna have to go back to the manual and set it correctly. My jetting formula came from the original Suzuki manual for jets that were in the Canada bound bike. 89-95 atleast Canadian bikes got 40/125. I should have talked to a few Canadian shop people but I was only there a yr so I never managed to make good contacts there.
Cool.
Buddha.
Quote from: MaxD on May 02, 2020, 11:06:57 AM
But, we are GS500 owners who need to protect the carbs, and what we apparently need to do that is a quick convenient way to drain the gas out of the carbs when the bike sits, then reprime to start back up. If the fuel selector had an "Off" position and not just On, Prime, and Reserve, we could switch off and run the engine till it sucked the carbs dry. Similarly, if we had a convenient bottom drain in the tank, we could periodically drain an ounce of water contaminated fuel out in order to be even better protected (keep tank from rusting).
The tank petcock already does both these things. Only 2 bolts to get to it (takes maybe 5 minutes). There are also threads on this forum about changing the vacuum operated frame petcock to a manual one off a CRF dirt bike. One less thing to fail, but one more thing to remember every ride.
No drain could ever truly get to the bottom of a GS500 tank. It has too many weird crevices and such where water could pool up. If the bike is going to be sitting longer than 6 months, better to drain the tank as best you can and fill it with just enough oil to slosh it around and coat the inside of the tank walls and then store the tank indoors off the bike. Reconnect and fill with fresh gas when you are ready to ride in the Spring/summer.
OK, sounds good except it would be nicer not to have to do even 5 minutes of disassembly to get to suck out the carbs.
Looking at the fuel system plumbing in my Clymer manual page 251, I think there is a better way than what I suggested above, a way which preserves the Reserve function and is quick and easy to use.
The output side of the fuel selector is a single line that goes to the T-fitting to split the fuel flow out to each carb. So, a simple ON-OFF valve could be inserted in that line and strapped to an easily accessible place on the frame.
To use it to suck out the carb (when not riding for a week or longer), start the engine, switch to PRIME to turn off the vacuum (in case a vacuum with fuel flow blocked is damaging to the fuel selector or carbs), then switch OFF the new valve. The carbs should get sucked dry in a minute and the engine will shut down. The selector can be left in PRIME with new valve OFF (which prevents refilling the carbs and associated leak problems) and carbs dry.
For the next start up, turn new valve ON with selector still in PRIME, start engine, switch regular fuel selector to ON, and off you go.
The only thing we would not have is an easy drain function for removing water, but as you point out its hard to drain from the very bottom of the tank if it does not have effectively a sump in the manner of a light aircraft fuel tank. I was assuming that the "reserve" portion of the tank would be something of a sump, since if you are into the reserve you need access to the last of the fuel in the tank.
But, even if there is not a good way to drain that water, there should be more water in the bottom of the tank. Thus, if you you use your trip odometer as an approximate fuel gauge, you could leave the fuel selector on Reserve as a way to pull out the more watery gas while riding. In fact, if you made a habit of using Reserve for just the first few minutes of riding, that would seem to significantly reduce the average water in the fuel.
It is a good habit to run on reserve ever so often if you don't frequently run all the way to reserve. In addition to the benefit you describe it also prevents running to reserve and then getting a dose of gummy 2 year old gasoline that has been sitting in the line.
Many a GStwinner has run out of gas because it looked like there was plenty of gas in the tank. The relatively flat bottom of the tank makes it difficult to get every last drop and easy to think you can see lots of gas in there.
I like your thinking, but wouldn't it be easier to mark your calendar every 3 months with "take GS for 2 hour ride." After all, this is why we own a motorcycle.
Thanks, it never occurred to me that there was an even stronger need to do some reserve running to get the old gas out of the reserve fuel line. That sent me straight out to the garage to run on reserve for a few minutes.
Well reserve is the lower 1/3 or something of the same tank.
Maybe it would clear out the pickup and the fuel line from the tank to the frame petcock but it would do nothing else for the tank.
In fact to get a better clearing out of the reserve tank - when you fill gas, aim it down in that left and right side crap pockets and let the gas flow agitate it - and really you don't want that crap in your carb, but well short of taking off the tank and pressure washing it and getting it de rusted etc etc this is the best bet.
Cool.
Buddha.