No power after winter storage

[Bluesmudge]

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.

[mr72]

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.

[MaxD]

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. 

[Joolstacho]

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'..."

[MaxD]

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?

[The Buddha]

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.

[Bluesmudge]

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.

[MaxD]

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.   

[Bluesmudge]

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.

[MaxD]

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. 

[The Buddha]

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.