I have had my F2 for about three years now (first sport bike and absolutely love it!). Have a majority of the work myself and have one last issue. Initially, my throttle was sticking and replaced the throttle sleeve, push & pull cables, and made sure that both the cables and throttle sleeve is lubed well. But, the throttle didn't snap back until the little latch that secures the air box was bent upwards just a little bit. It was pushing against the throttle cables -- now the throttle snaps back every time with the air box and as tank on. Ok... That issue fixed.

But, there is one last issue that I am having a problem with and looking for thoughts/ideas. The throttle snaps back with no problems. But, when rev'ing the engine at idle, the engine doesn't idle back quickly. It takes a few seconds then it idles back to the normal idle (around 1100rpm). This is very noticeable when shifting when riding. Regardless of up shifting or downshifting - the results are the same: when the clutch is disengaged, the idle shoots up 2-3k, stays there, and then comes down to about 1500 after about 5-10 seconds.

I am certain that the cables were routed back the same way that the original cables were and that the correct ones were replaced (push cable with push cable and pull cable with pull cable.) I see that others have similar problems but were resolved with lubing the existing cables or replacing them. Is there something else that I may be missing?

 

I used to have a hanging idle like that too, turned out to be the position of the cables. Try turning the right hand switch ( ya the one containing the starter button and throttle cables) up or downwards and see if it helps out at all. It worked in my case.

If that doesnt do it, it might be a vacuum leak or time for a carb cleaning

 

also, that is a sign that your idle is set incorrectly. you said that it idles at 1100, which is about right, but it is worth a shot to play with the idle set screw begind the petcock and see what happens. about a quarter turn ccw at a time and retry.

 

idle should be around 1300 I thought? I had mine that high 1100 is way to low if mine ever dipped that low

 

I think that I found the problem; Actually there were several. Took the carbs off and cleaned all of them out. Carb #1 jet was almost clogged. Next there was a vacuum hose missing from Carb #2. After that the bike ran significantly better. Had the carbs synced and its like a new bike! No engine surges during idle. No engine surges when shifting. Idle is at a steady and consistant 900 - 1000 RPMs.

Thanks for the help!

 

You want your idle at 1200rpms ideally.

I was going to suggest a carb issue. Usually if it hangs like that it means it's running a bit rich. Odd that you found a clogged jet however!