what are compatable engines?
 

im looking for an f2 engine but am not having much luck, what are some other engines that can fit in an f2 frame? that way i can broaden my search

F3 engine plugs right in, 900rr fits with modifications.

I'm putting an F3 motor in my F2, better transmission and a claimed 10hp over the F2.

That "claimed" 10hp is only really due to the Ram air system that was added to the F3. Unless your ripping the road up near top speeds, you will never feel that power difference.

never say never

do u need any other wiring or does the f3 engine plug right up?

Use your old F2 carb & airbox and it will bolt/plug right in.

But you lose the ram-air system then.

Ram air system adds too much weight to be worthwhile

And that's a very good thing. Here's what I wrote the last time someone asked about putting an F3 engine in an F2.

Hope I can help a bit here. Use the F2 carbs and airbox. It's the best option. Here's why.

In order to get the F3 carbs to work right, you have to use the ram air system. That included all the hose, ram air scoop, F3 airbox, those other little air intake things, I forget what they are called right now, but they pressurize the carbs float bowls. It's a mess of hoses and peices and it all has to be hooked up exactly right in order to work right. In addition, you'll need a fuel pump, pump relay, a fuse, and wiring to wire that up, like F3's do since you can't gravity feed the carbs any more.

But here's the upside of the conversion. You've added weight to the bike. You've added complexing. you've got more things that can fail and leave you stranded 75 miles from home. The ram air blocks the lower triples, so forget using your frontend stand any more. And finally, for all your hard work, money, time and effort, you've added ZERO hp by doing this. It's a complete waste.

Phil