Is your Carb Level?

[Zman]

My son's 250 was running out of fuel at high rpms even after I set the float height correctly. To make a long story short, I realized that the carb was not mounted level. By eye it can be difficult to set the carb level because it is on two separate angles relative to the engine.

With the bike on a stand with the tank off I put a construction level across the frame. I shimmed the bike to make it level. I then put the level on the top of the carb and found that what I thought looked correct was far from actual level. That angle prevented the carb from filling the float bowl completely and caused it to run out of fuel at high rpms. I initially had the carb tilted outward and to correct the problem I needed to rotate the carb top away from me (towards the center of the bike). This small change fixed the problem.

FYI- when the carb was set level the cable was in contact with the fuel tank.

 

[Selvagem]

Also I've been through this situation. In my case, I first installed the carburetor in its proper place on the bike, done that, with the help of an inclinometer, checked the result. After this, I adjusted the float level in the same inclination that I have when the carburetor is installed. To see the results, I used a transparent hose adapted to the tank drain plug, as indicated in this link:

http://www.gasgasrider.org/forum/showthread.php?t=10173&highlight=float+set

I can say that the result was excellent, it does not leak fuel and have no high RPM missing problem not in a position to high requirements.