G'day everyone, at the end of this season the engine from my NC35 racebike will definitely need to be refreshed, the poor old girl is a bit worn out and the lack of power is noticeable once I click into 6th gear along Phillip Island's front straight and she doesn't want to pull very much at all.

I'm keen to rebuild the engine myself as I love to tinker, I perform all maintenance on my bikes and can follow a manual pretty well. So apart from piston rings, valve seals and possibly crank bearings, is there anything else I should be doing while the engine is apart?

Is there any value getting the heads cleaned up and flowed, taking weight off the crank, etc?

I'm looking for ways to get as much reliable power from the engine as I'm legally allowed (so no big bores or stroked cranks) to counteract the power to weight disadvantage I have (I'm pushing 90kg on a good day!).

Thanks in advance for any help provided

I assume that the bike pulled sixth gear better at the start of the season and simply does not require a gearing change.

You should check your class regs for eligibility of engine component changes and also physical interchangeability, but NC30 heads may have larger valves and I know the carbies are larger. Heads could be skimmed for more compression, 11.3 is low for a race engine these days.

Cheers, thanks for the reply Magg. The racing series I'm involved in basically states capacity cannot be increased and you can't go too crazy with light billet cranks, etc. But raising compression a bit is a good idea.

I think I'll get a bit more info from our local 400 specialist to see what he recommends. I'll post up what changes I've made once this season finishes in August.