Motorcycle mechanics chime in

[Rightwinger]

My bike is in the shop. Since last spring, about 6 or 7 times, my Suzuki GS500F would for no reason, start leaking fuel from an overflow/drain tube. No rhyme or reason. First time I had just come home from work and then gone over to the ball field to watch my sons practice. A fellow parent told me my bike was leaking. It was on the center stand and it was a definite steady drip. I started the bike and moved it and it stopped. The next times were all when it was sitting either on the center stand or kick stand. Many times after sitting for several days. It would start sluggishly and sometimes took a bit of cranking to get it going. It would always stop. The last one was two weeks ago, a week after I had started it and rode it about 10 miles just to get it warm and fluids all stirred up again. It got really cold that week just before that last snow bout. I come out and almost a full tank of fuel with stabilizer in it had leaked out.

I'm thinking a float is messed up but don't know.

Now, its in the shop at Precision Motor Sports over in Providence, Mt. Juliet. They call and tell me I need two new jets and that the petcock on the fuel line need replacing. Nothing about the floats. It's a dual carb system and the bike has a little over 6K miles on it and will be two years old in May. I noted when turning it in that no familiar faces were present and the tech did say they had to let a few people go. Now I get the news that things I didn't even think about need replacing. Am I wrong for being a bit suspicious?

Anyone else had a similar issue with their bike?

[Guest Baddawg865]

That doesn't sound right to me. I could be totally wrong, but it shouldn't have anything to do with the jets. I would get a second opinion. The float sounds like a good possibility. My buddies R1 was doing something similar, and they said the pressure in the tank was making it overflow.

[56FordGuy]

I've said it before, never heard of jets causing a leak. Not a dual carb expert, though. Might be something weird going on there. Fuel valve seems possible.

Baddawg made a good point, the fuel tank vent could be stopped up. Under the right atmospheric conditions, the pressure difference could cause a leak. Not sure how the bike would be vented, though. Some stuff uses vented fuel caps, other stuff has a separate vent hose somewhere.

[Rightwinger]

Been doing my own research and I found this on the GStwins forum.

It's funny how either this is a common thing to the GS500 or my tech reads the same things.

gas tank leaks and i cant figure it out!

[Guest ArmyVeteran37214]

Winger, what year is your GS500F? I have an 07 and I haven't had a problem yet, (knock on wood)!

[lowbud]

My guess would be the floats. I don't have the bike but have rebuild many carbs in my day. jets and passages are only used when the bike is running and vacume is present.

Could be the needle not seatng or float out of adjustment and flooding the overflow passages.

See if it leaks with the gas cap off. it's possible it may be casued by pressure too.

just my opinion.

Edited February 24, 2010 by lowbud

[Rightwinger]

Winger, what year is your GS500F? I have an 07 and I haven't had a problem yet, (knock on wood)!

It's an 07 StreetWK05. Its been a fun bike except for this. I'm okay with them replacing all this if they can show me how both sections could go bad. The more I think and read, it should be one or the other, not both a problem in the petcock AND jets or floats. They also haven't called me back since last Tuesday. I would think if things are slow, they should have paid lots of attention to a NON warranty bike in the shop.

Guess I'm more frustrated that Saturday was the first riding weather day we've had in forever and I didn't even have the chance.

I'll ask for the "worn" parts, which should be standard at any shop.

[56FordGuy]

I'll ask for the "worn" parts, which should be standard at any shop.

Be sure you let them know that before they work on it. Most customers don't care, and it's usually SOP for all damaged/ bad parts to go straight to the dumpster.

[Fadex]

I definitely no motorcycle guru but a buddy of mine owns Cycle Concepts in Murfreesboro. You might give him a call and see what he thinks.

[Armed Aviator]

Its the Alcohol in the gas. Eats the seals. Quit buring Ethonal or replace the seals in the float needle valve with alcohol proof seals. Also your floats might need adjusting.

Edited February 24, 2010 by Armed Aviator

[Guest Jeremey]

I have seen NUMEROUS carburetor problems since the great idea to make all gasoline contain 10% ethanol. Alcohol is very hard on rubber parts. The tip of the needle in the needle and seat assemblies are typically rubber coated. The alcohol erodes a small amount of the rubber away to the point where the needle will no longer seal to the seat. This causes your float bowls to over fill and gas to trickle out of the bowl overflow tube.

I cant tell you how many fuel tank to carb gaskets I have changed on Briggs and Stratton engines where the rubber diaphragm has shrunken to the point either the mower wont run at all, or the engine speed races up and down erratically.

And the jets will not cause fuel to leak out onto the ground.

[Rightwinger]

+1 on the alcohol. I run this blue stuff that my local NAPA guy/shop turned me onto that is supposed to assist in protecting the fuel system from ethanol. I can't recall the name of it but this guy wouldn't sell me something just to sell me something. It may have been to late as I started using it last spring after the first carb balancing. I'll keep using it once she is back and running right again.

[R1100R]

I would say the the needle and seat for the floats also. I learn a long time ago to shut the petcock off when not riding. I have had less problems with Carburetor issues

over the years. Especially if the bike sits for more than a week.

[peejman]

Which overflow/drain hose is the fuel coming from?

If it's the tank overflow hose, then you likely have a clogged/pinched vent hose.

If it's the carb overflow hose, then it's like the float/needle issues mentioned.

I rode a '93 GS500 for a couple of years, they're fun bikes. If you're reasonably mechanically inclined, working on the carbs is pretty easy. A good shop manual will walk you through it step-by-step.

And yes, the ethanol in gas sucks. The tank rusted on my CBR and I've had to repair it and go through the entire fuel system to clean everything out.

Oh, and there's a good group of riders here ... http://www.easttnriders.com/forum/index.php

[molonlabetn]

Sounds like a float issue to me, as well.

[Guest no_masters]

you could always take it to America's motorsports in rivergate or on 8th ave for a second opinion. they have always been straight with me.

[Rightwinger]

Bike was bought at America's Motorsports (Rivergate) and it will never darken their doorstep again.

Seems to be a common issue with these models and carbs as I looked over at the GStwins site. Shop still hasn't called back to say they have it repaired yet.

Gas was leaking from the carb overflow tube. The one that looks like its sealed with the flanges on it.

I may get my hands dirty on it going forward if it presents any further issues. There is a lot of good self help info at that site and I will find a manual for it ASAP.

I hope I never have to replace a tank on this thing as I was looking over the parts list schematic and a new tank is listed at over 700 bucks retail!

[gregintenn]

Go get it and take it to Grady Short in Gamaliel Kentucky. He owns Gamaliel Riding Supply. He mainly works on four wheelers and dirt bikes, but I imagine he'd be glad to help you. He's a great guy and a straight shooter.

I'm glad you started this thread, as my four wheeler is leaking gas out of the carbeurator overflow tube as well. I'm going to get into it when I have a couple of spare hours, and you've given me some ideas of things to look at.

[Rightwinger]

I may look at Gamaliel in the future. I go up there to Shooting Supply for reloading supplies. Amazing what that small town has in it isn't it.

For now, its at Precision for this round. I'm probably making this bigger than it really is. The jets probably are the issue and not sealing due to the first year of ethanol fuel. I made it clear to them that I bought the GS500F because I did not want to spend what it would take to get a Gixxer or a V-strom. Hopefully they want to make money on the long plan and not all at once.

[Rightwinger]

Shop called today. It's all put back together except for a seal under the petcock that they had to order when they found it dry rotted.

Bill is going to be $563.00

I'll be posting a firearm to sell here in a few minutes...sheesh.

[Guest ArmyVeteran37214]

Bill is going to be $563.00

Ouch, I guess I might wanna pickup a repair manual for my gs500f.

Edited February 26, 2010 by StreetWK05

[Smith]

Shop called today. It's all put back together except for a seal under the petcock that they had to order when they found it dry rotted.

Bill is going to be $563.00

I'll be posting a firearm to sell here in a few minutes...sheesh.

WOW! That seems steep for what they said they did.

[Guest tnrider]

because you only call it an overflow tube so I am not sure about this. Also I ride another make bike. Mine does have an overflow tube also but it is there to drain too much fuel out of the tank, not carbs. If I top off too much on a warm day, I can park the scoot in the garage, later come out and find a puddle under the bike and the garage full of fumes. Not sure what you do, but I often fill my tank at the end of a ride to keep condensate from accumulating in there. In the warm garage, or sometimes on a hot day outside, fuel expands and flows out of the "puke" tube. Just possible this is what is happening in your case and the tube is doing some sort of a siphoning action.

It does seem strange to me also that there should be this many things that need to be replaced. I would want to get a second opinion too. Good luck and keep the rubber side down.

[peejman]

$563!! I knew there was a reason why I do my own wrenching.

I had the Haynes manual for my GS500... between it and gstwins.com, that's all the info you'll need.

[Rightwinger]

because you only call it an overflow tube so I am not sure about this. Also I ride another make bike. Mine does have an overflow tube also but it is there to drain too much fuel out of the tank, not carbs. If I top off too much on a warm day, I can park the scoot in the garage, later come out and find a puddle under the bike and the garage full of fumes. Not sure what you do, but I often fill my tank at the end of a ride to keep condensate from accumulating in there. In the warm garage, or sometimes on a hot day outside, fuel expands and flows out of the "puke" tube. Just possible this is what is happening in your case and the tube is doing some sort of a siphoning action.

It does seem strange to me also that there should be this many things that need to be replaced. I would want to get a second opinion too. Good luck and keep the rubber side down.

There are two drain tubes that come down in the same spot, one is the tank overflow, this is the carb one. This one allowed the entire tank of gas to drain and in sub freezing weather, not much chance of expansion there. I will be seeking to increase my mechanical prowess with this but I am NOT a mechanic. Changing oil, lubing the chain, I even swapped out the upper aero of the fairing with no difficulty. Getting into the guts of a dual carb system though when you have no training could keep it on the sidelines and cost me close to this in mistakes.

So, just because I never looked, which gas companies still market ethanol free fuel?