2005 gs500f wont Idle after replacing Carbs

[Blaircroft]

Okay im new here and this looks like a very helpful place with a wealth of knowledge. I am a novice bike owner/rider but mechanically inclined.. However my first learning bike turned out to be a project bike. Which is great because im having so much fun rebuilding it.. The problem...

I have done countless things to this bike which has made it better and better since I purchased it. However at the pinnacle of its evolution I topped it out on the backroads and blew the stator cover gasket which I used a temporary liquid gasket (high temp sealant) which is working fine (no oil leaks). I have since purchased the factory gasket and plan on putting it on.

I also completely blew the left side carb. It ceased to open and close, floaters were sticking. pretty obviously. Then I looked and to my surprise discovered the left carb was jacked and the bowl covers were stripped out.. This appears to have been a long standing problem that I wasnt told about at the purchase...

So I ordered a factory tested (rebuilt) carb which seems to be working fine. There was extra vacuum 3-way fittings I assume go on the models that have the canisters as all other lines are hooked up properly. I capped one line off and bypassed the other back into itself until I get a couple two way fittings..

The problem Im having now since the problem occurred and corrected and it sat for about a week. The idle is completely wacked. It cranks up no problems. However it will not idle unless the choke is completely on and even that ceases to work after time. I turned the throttle knob beneath the carb all the way and backed it off quite a bit then I held the throttle to about 2000rpms for 5-10 min without dying but even after that instantly die when I let go of the throttle.

I rode it down the street with no problems as long as I held the throttle to 2000rpms or higher but I then discovered that it will not go past 5000rpms in any gear. So im stuck in gears low-3.

This has now gone out of my realm of mechanical inclination. Ive searched this forum and google for answers mostly unrelated problems with few similarities. Seems like I remember noticing the spark plug wire caps not screwing into the brand new spark plugs (I gaped at .32).

Any intermediate ideas please and thank you!

[The Buddha]

Tight valves.
Cool.
Buddha.

[mchollan]

+1 Buddha, check the valve gaps.  You'll also need to balance the carbs to get it running right.

[Blaircroft]

+1 Buddha, check the valve gaps.  You'll also need to balance the carbs to get it running right.

Thanks for the reply

A new development. I discovered that I left the boot clamps pretty loose. Upon tightening those now all it does is backfire and doesnt crank. Its a pretty loud backfire as the police were called to investigate.. I worked on it for 5 hours yesterday and it is getting pretty chilly. Around 2pm it was starting up with the boots loosened and warming up by 5-6pm its dark and temp drops dramatically. The engines cold at this point and not cranking. Just backfiring..

So you think t he Valves in the engine are too high (tight)? It was running perfectly with the other carb until it totally blew out.. Also the guy I bought the carb from told me it was taken out of a running bike that had no issues.. Whats the next step?

[Blaircroft]

+1 Buddha, check the valve gaps.  You'll also need to balance the carbs to get it running right.

Thanks for the reply

A new development. I discovered that I left the boot clamps pretty loose. Upon tightening those now all it does is backfire and doesnt crank. Its a pretty loud backfire as the police were called to investigate.. I worked on it for 5 hours yesterday and it is getting pretty chilly. Around 2pm it was starting up with the boots loosened and warming up by 5-6pm its dark and temp drops dramatically. The engines cold at this point and not cranking. Just backfiring..

So you think t he Valves in the engine are too high (tight)? It was running perfectly with the other carb until it totally blew out.. Also the guy I bought the carb from told me it was taken out of a running bike that had no issues.. Whats the next step?

Thanks for reply.

The Valve clearance was a result of the carb blowing out? Or is that just a troubleshooting tip to completely rule it out?

[The Buddha]

OK the first problem isn't neccesarily tight valves, its the free air coming in through the manifold.

So ignore valves for a second ... OK you can still ahve tight valves, so dont ignore em.

Back firing and not starting - you do something else, like change spark plugs ?

Cool.
Buddha.

[radodrill]

Also the guy I bought the carb from told me it was taken out of a running bike that had no issues.

Could be that the pre-owned carbs you bought had been rejetted (e.g. for a performance exhaust) and those jets aren't compatible with your bike setup.  If the jets were sized for a lunchbox and performance exhaust, then the Air/fuel mix would be way too rich for a stock exhaust/filter.  This would explain why it runs if you loosen the intake boots as that allows more air in thus leaning out the overly rich mixture.

[Blaircroft]

OK the first problem isn't neccesarily tight valves, its the free air coming in through the manifold.

So ignore valves for a second ... OK you can still ahve tight valves, so dont ignore em.

Back firing and not starting - you do something else, like change spark plugs ?

Cool.
Buddha.

The only thing thats different is the carb and it wasnt hooked up right to begin with ( vacuum lines bypassed back into a loop)

[Blaircroft]

Also the guy I bought the carb from told me it was taken out of a running bike that had no issues.

Could be that the pre-owned carbs you bought had been rejetted (e.g. for a performance exhaust) and those jets aren't compatible with your bike setup.  If the jets were sized for a lunchbox and performance exhaust, then the Air/fuel mix would be way too rich for a stock exhaust/filter.  This would explain why it runs if you loosen the intake boots as that allows more air in thus leaning out the overly rich mixture.

Someone else said that too. I was afraid of that but it sure does make alot of sense. So I have to re jet this carb?

[radodrill]

Someone else said that too. I was afraid of that but it sure does make alot of sense. So I have to re jet this carb?

I would check the jetting; the sizes are stamped on the bottom on the mains and on the side of the pilot.  The stock sizes are 17.5/60/130, though many people with a stock bike run 20/60/135 as the bike is typically jetted lean from the factory.  If the jets check out, then you may have some additional issues.

[Blaircroft]

It has been running extremely rich since I tuned it and I like and want that. Before the carb blew out it was running pretty close to my friends Kawasaki 636. Which might be why the carb gave out. Haha..

[radodrill]

It has been running extremely rich since I tuned it and I like and want that. Before the carb blew out it was running pretty close to my friends Kawasaki 636. Which might be why the carb gave out. Haha..

I drastically upsized the mains on my GS as well.  I'm sitting at 20/62.5/142.5 and very happy with that.  At first Buddha thought that was way too rich, now he thinks it's lean 

[The Buddha]

It has been running extremely rich since I tuned it and I like and want that. Before the carb blew out it was running pretty close to my friends Kawasaki 636. Which might be why the carb gave out. Haha..

I drastically upsized the mains on my GS as well.  I'm sitting at 20/62.5/142.5 and very happy with that.  At first Buddha thought that was way too rich, now he thinks it's lean 

That's cos, Making good power = you cant be rich. You can be lean ... even if it is so lean it surges and misfires, it will make good power under changing throttle conditions. It will only act up @ steady throttle.
Cool.
Buddha.

[RossLH]

At first Buddha thought that was way too rich, now he thinks it's lean 

It's lean because your floats aren't set right, not because of the jets.


And the horse is officially dead. Look what you've made me do.