I am about to have my engine done, who makes the major HP. The quad is used for tt/flattrack only.

 

Go to www.lrdperformance.com and see if one of their kits might interest you. I had thought about one of their engine kits but have decided to just rebuild back with a stock cylinder and try to sell it. I'm starting to get the Z400 bug, plus I'm tired of doing more wrenching than riding.

 

I was thinking about going with a LRD 300 kit when I had the LT. But, it's gone now and just waiting to pick up the Z400. I have heard really good things about FTZ. Check out their website at http://www.ftzracing.com/.