yep, 109bhp in that frame is too much, (I bought that off Yazza) and dropped the carbs to 35mms and then retuned it, still ended up at 109bhp, but with better low down manners, but still an animal when it came on the pipe, it eventually bit back and crashed on a track day
, since then its been sat in the naughty corner
waiting for me to fix it and retune it to be a little less agressive !
The RS421 I had was much more civilised in comparison and I've got a 421 wampus which is huge fun, stupid bottom end power, but peaks around 75bhp at the moment, its in a YPVS frame, so plenty for that frame
My new RS I am building will be around the 110bhp to 120bhp mark, but with loads of mods and special parts, with a target weight of 120kgs wet, that will be fun, but I am spending alot of time sorting out bottom end drive-ability as much as targetting good peak power numbers
The 535 engine I built that hit 122bhp in an LC frame is a great engine, very tractable and loads of grunt everywhere, but that engine cost a fortune to build and refine to what it is today, its due some upgrades, so should see 130+bhp all being well, but the aim is to keep the bottom end and rideability as well, time will tell if I can do that, the frame of course is overwhelemd by the power when it comes in
The big factor in all of the above is cost, if you've deep pockets and you can afford to solve all the problems a big powered 2 stroke will throw at you, not just in the engine department, but cooling, suspension, frame/chassis etc, then go for it, but if you've a budget to work to, then I'd lower your sights, get a good useable powered engine and work out what else needs tweaking chassis etc wise, as you could end up with something unrideable if the chassis and suspension can't handle the power etc