|
Best bang for your buck as long as torque is concerned is to overbore the engine (not substitute for cubic inches as they say) but it would increase capacity so the FE can suffer.
I polished the piston crown and cylinder head (more reflecting allows for more air expansion) since it is free.
Boosting the CR is especially good from bottom to midrange, no gain up top.
My exhaust port modding turns out to be more a pet project than something useful I am affraid.
Is your bike a two valver ?
You could have the camshaft grinded for more lift instead of more duration.
There was a guy called motoman who epoxied his inlet port for more midrange but it was on a liquid cooled bike, I wouldn't do it on a air cooled engine.
A smaller more free flowing carb can be a good torque booster but you won't find any that small I am affraid (maybe one of the old Kawasaki I4 had 28 or 30 mm pumper carbs) but that sounds like a lot of work as far as tuning is concerned.
A free flowing exhaust can boost FE but it is detrimental to mid-range torque.
__________________
|