im working on somthing new and i feel i have to understand the difference between the f2 fuel tank and the f3 fuel tank OR why the f3 needs a fuel pump and the f2 doesnt
by the way gravity feed feels like crap just bought a fuel pump everythings flowing smooth again but thats what got my gears going
but was the f2 motor at a steeper angle making fuel flow easier to the carbs or the tank shaped a little different

 

I'm not entirely sure but I do recall reading that the f2 has a vacuum assisted petcock iirc. Fwiw I've been gravity feeding the carbs on my f3 and have noticed little to no difference in performance. And that's with many highway runs around the 11k rpm area

 

yep F2 has a vacuum operated petcock.

Frames are identical, and motors swap, so there's no difference in the angles or anything.

 

You can use the F3 petcock on the F2. Gravity feeding the F3 will cause issues when the engine is in the upper revs for a period of time. It starves the carbs of needed fuel. The carbs are different.

 

Yes, when you are in the upper revs, you will lose power due to empty bowls for a long period of time. i have a F2 and spliced in a F3 harness, pump, petcock and ecu. Never had another problem again and have continuos power in the upper rev.

 

You do not need a pump while using a F3 petcock on a F2. The F3 petcock is a good upgrade for a F2.

 

True! Though every time you turn off the power, the petcock would need to be also turned to the "Off" position or run the risk off flooding the motor. A common problem with the F3 petcock on the F2's.

 

I recommend turning the petcock off on F3's too. I know I do it on both of mine. Just a good habit you learn after you find fuel pouring out of the carbs.....

 

Frames are not identical.They are VERY similar though.

Yes,the motors swap.Yes an F3 can run on an F2 harness,just no TPS.

The reason for the fuel pump is the ram air on the F3.The fuel pump provides about 3-4 psi extra flow.Long pulls in 4th gear will run the carbs dry,causing the bike to shut down.Ask me how I know,found this out the hard way.

F3 petcock is a nice upgrade.

The fuel pumps rarely fail,it's the ignition-style points inside that wear out. K&L makes a replacement part for them.

F2 and F3 tanks are identical except for the paint schemes.

Hope this helps

 

The King has spoken!