So i blew my headgasket a couple weeks ago along with a piston and a cylinder wall (never order parts from ronayers or w/e the **** it is, idiots sent me the wrong headgasket, **** never matched up) anyways. After replacing it changing out the pistons and cylinder heads and putting this crap all back together. my motor was having some issues starting, and once i finally did the bike ran like crap. Super under powered and almost like it was mis firing. Any ideas? Im thinking the plugs are shot after being submerged in 80 billion degree coolant

 

If you're positive the cam timing was set perfectly, then I would definitely start simple, hoping it's the plugs!

 

Took off the vc and the timing jumped fixed the timing and now it won't start at all. It backfires sometimes but besides that it doesn't sound like it wants to launch up

 

valves all in spec?

 

who knows, bike had like little to no compression tho, sooo dropped the motor again and need to order new rings. Tried re using old ones and looks like it backfired. Oh wellzzzzz any site recommendations for ordering? not going with ronayers because this is basically their fault to begin with1

 

I have not had to re-build my F2 motor (yet), but if and when I do, I will probably only use Wiseco products:

Motorcycle Forged Pistons & Performance Parts - Wiseco Piston Inc.

 

ooooo if i had the money to drop on this i would love to make it a 637

 

Oh yes, me too!! One day...

 

Man, I have said many times, the F4i pistons are exactly spec at the lowest fractional cost. F4i compression is 12:1 and wiseco are 13:1, but cbrzone has the 637 .018 big bore head gasket to make that up. You will spend less money on are outdated relic like ours.

 

That's good to know, but I was trying to point him toward the rings...now, are you saying that the F4i pistons are the same spec as the F2, albeit with higher compression domes, and/or interchangable rings? Or are you saying that the F4i pistons are the same spec as the 637 cc big bore kit? I've not worked on F4i's at all, but I thought they were only 599 cc, just like the F2.