I know I get bitched about a lot elsewhere for saying stick to the stock parts, but the simple fact is they work so well. The core motor from 88 onwards is pretty much the same throughout, although [very basically] the compression and port timing has evolved, so can fairly easily be swapped at will (taking into account neutral switches, GPS, pulser coils, flywheels etc.). But it's all the little niggly bits that were attached and updated along the way that can cause the headaches. We've been lucky enough over the years to have access to all the HRC (and many aftermarket) parts, from MC16 to MC28, and many of the NF5 bikes/parts too, and a dyno to compare results of years of both our tinkering, and other people's.
Always start of with the best stock setup you can, then proceed from there. There's absolutely no reason whatsoever a stock healthy 88-93 (the MC28's obviously a little different) won't kick out 60+rwhp, which is a great starting point, and better than any of their contemporary 250s.
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Andy.
NSR-WORLD.COM
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