[edmyser]

Hey guys, been working on this bike for a while and the problem has always been the carbs. It has to do with jetting (still working on it) and it's a long story. I was hoping someone could simply answer a curious question. The pictures I posted below are of the gas tank nipples, and where they mount on the carbs. (they got uploaded sideways so bare with me) Common sense tells me that there are two nipples and two feed lines for the carbs, and that must be how they are routed, meaning the amount of fuel must be distributed evenly between them and that's how I've always routed them. I however was no the first person to put my hands on this bike and just want to make sure I am routing them correctly. The picture in the manual doesn't help either.

The petcock on these bikes are rather weird because there is no OFF. only ON, PRI (primary?) and RES (reserve). Again, I am just looking for some knowledge regarding how the fuel is delivered to the carbs via the gas tank.
-Ed

 

[b3w4r3]

There should be a vacuum hose attached to the petcock. It comes from the number 3 carb I believe and is attached to the nipple on top of the carb cap. The On position functions as the off when the bike is not running and there is no vacuum. The reserve also only flows fuel when there is vacuum. The PRI is prime which allows the fuel to free flow without vacuum.

With the stock airbox the main jets should be 117.5 (outer cylinders), and 120 (inner cylinders). The pilot jet is 32.5. After market pipes might need a bigger main.

 

[edmyser]

Yes, there is definitely a vaccum line that attaches to the #3 carb coming from the petcock. I guess i just wanted to make sure that the fuel lines from the petcock are corrected routed to the carbs. Maybe i can pick your brain a little more or maybe ill start another thread but check this out. After synchronizing the carbs with the $100 motion pro sync pro tool, the bike is still giving me the same result as it did before which leads me to believe I need to change some different jets. What the bike is doing, is bogging out below like 6k RPM's and just struggles to rev smoothly, after that the bike is a frikkin missile. again, ever function of the bike is great, it idles fine, its just coming off idle up to about 6k rpms It appears that the air/fuel ratio is off or something. Ill try to upload some videos if i can.
Thanks in advance
-Ed

 

[wombat58]

Check the carb metering needles and the mating jet tubes for wear . . . common problem, easily fixed.