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Main Area => General GS500 Discussion => Topic started by: weedahoe on October 02, 2012, 10:29:58 PM

Title: carb PITA issues
Post by: weedahoe on October 02, 2012, 10:29:58 PM
So after having my bike apart for a while due to other work, I finally got the carbs back on. I also bought a pair of Factory Pro extended air mixture screws (Thanks to Adidas for pointing them out) and they are awesome.

Anyway, carbs worked great prior to removal. But when I put them back on, the left carb leaked fuel. UGH....It was leaking from one of the two small holes on the back of the carbs where the air filter mounts

So I pulled them back off. Removed the bowl and checked everything. It all looked good. Put it back together, opened the petcock and it leaks again. WTF?

So I pulled it off again and pulled it apart. I tested the float and made sure it was seating and closing off fuel and it was. Put it all back together and installed them and the left side is now fine. No leaks. Except........not the right side does the same thing. Really? WTF?

So, I did the same thing, pulled them off, pulled them apart, checked and rechecked. Tested and retested. Put it back together and now I have no leaks and everything runs fine.

Now I checked all over on how to adjust the float height and could not find anything on 04+. I looked at the floats and didnt see how they could be adjusted. I also didnt have any clear hose to check the float height from the bowl. So Im assuming the floats were sticking? Is this normal? Any reason as to why?
Title: Re: carb PITA issues
Post by: adidasguy on October 03, 2012, 03:44:47 PM
I recall floats adjust the same way: bend the tab up or down a little.

Where was the gas supply when you were testing? When I use a MotionPro shop tank, I have to be sure the bottom of it is no more than a foot above the true bottom of where the tank would be.

Our fuel is gravity fed. Gas supply too high means gravity is doing a lot of work. More work than the carb floats can overcome so gas spits out the air intake side of the carbs.
Title: Re: carb PITA issues
Post by: weedahoe on October 03, 2012, 04:20:17 PM
Thanks for the reply. I was getting worried there for a while ;)

Fuel supply was the tank sitting on the frame. On the floats, I didnt see a metal tang as was mentioned in many other threads about float issues. The only thing that looked like it controlled the level of the float was a small plastic "nipple" on the back of the carb that rests against the brass tube where the needle valve sits in. I thought i had taken pics of it but I guess I didnt.
Title: Re: carb PITA issues
Post by: craigs449 on October 04, 2012, 04:37:07 AM
Quote from: weedahoe on October 03, 2012, 04:20:17 PM
Thanks for the reply. I was getting worried there for a while ;)

Fuel supply was the tank sitting on the frame. On the floats, I didnt see a metal tang as was mentioned in many other threads about float issues. The only thing that looked like it controlled the level of the float was a small plastic "nipple" on the back of the carb that rests against the brass tube where the needle valve sits in. I thought i had taken pics of it but I guess I didnt.

That is your needle valve.....the metal tab that the needle valve spring attaches to is the "tang" that gets adjusted (for lack of a better term) to adjust the float height. As I remember, the float height on the newer bikes is the same as my 01 which is 13mm +/- 1mm......be sure to measure the float height from the lowest point of the float to the bottom of the carb body where the float bowl mates up to it....and be sure that the needle valve is seated, but the needle valve spring is not compressed