Does anyone know h.p. rating for '86 trx 250r?What amount of power gain can I expect from adding FMF fatty pipe w/ T.c. 2, Boyesen power reeds, reed spacer, K@N filter. My machine is currently bone stock [I still love it!]what tires will last longer-Holeshots or shredders? everyones help will be much appreciated,

 

I believe the stock hp was around 39.5

and I'd say you'll maybe get aprox. a 10 hp gain from the mods you mentioned

just a guess

 

would that be 39HP at the crank?

 

THis is only a guess but at the rear wheels I say a stock one has about 33-35 at the rear wheels. I have a FMF fatty pipe,power core 2 silencer,boyesen reeds,port and polish,wiseco .020 piston,uni filter,rejet.

I have these on an 86 and it is FAST.When it was stock I beat my cousins 400ex and now I really beat him! By ALOT.

 

Sorry but the stock HP was not 39.5! It is about 32-33 HP you might be able to get to 40 without porting.