250ES engine questions for you gurus out there

[TheRealFatShady]

Hi,

Just got a 250es, want to make it as badass as possible.
Barnett clutch so the stock one won't slip with more power.

For a top end, can I use a full xr250 4 valve head + cylinder? (Fear the valve recesses are cut wrong, according to this post) How about a full 400ex top end or 300ex? (Or anywhere I can just find a big bore kit?)

I've thought about using a full TRX300 engine, would that be the easier/cheaper route?

Also plan for an exhaust, 400es or 350x carb, and higher performance cam - any recommendations on which? This hopefully will be like the two 'big camo' BR's.

[Thorpe]

TRX 300 would be a sweet way to go... I believe I read that you can punch the trx motor up to (dont quote me) 420cc range... Web Cams. has a pretty snotty cam for the ES... I had the same dream of lifting my BR and building a ratty motor for it, but after adding up the nickels, I decided to leave mine stock...