I'm thinking of getting the big bore kit for my MC21. I'd like to get some feedback about the kit and whatelse do you guys figure I should know.

Is there anything else I should change - jettings, exhaust system, air filter etc. I hear that the exhaust manifolds will only fit Tygas exhaust pipes.

I use the bike only for racing in our local road racing series.

Having test ridden TYGA's 300 "demonstrator" (thanks Matt!) I can say the ride is, er... interesting!! :D

There's undoubtedly a heap of torque and hp; and with well set up carbs and pipes it should certainly be in the low 70's I'd say, with the potential for 80hp if tuned with anger!! It is the torque that gets you hooked though! Gear changes are a lot less frantic and/or necessary, with 5th and 6th gear "roll-ons" more akin to a very well tuned VFR, but some would say that this is taking the essence of a 250 2-stroke away. The engine characteristics would be great on the track though, where the smooth, flat, long torque curve will make drive out of turns extremely usable.

Are you allowed to run 300cc's in your race class? Most series would not allow you to race with oversized cylinders... if they knew of course! Unlike the RS250 cylinders though, the barrels used for the TYGA conversion have a completely different exterior shape compared to that of the NSR250 items, so are easily spotted by any keen-eyed official!

What you cannot take away from the TYGA Performance kit is the quality. The replacement barrels are genuine Honda parts, produced in Japan to Honda's exacting tolerances, and all the necessary parts are included in the kit for very easy fitment. The kit has also gone though extensive road and track testing, and even NSR-WORLD's own Luke "destroyer" Fabian couldn't kill his! :lol:

The kit, as you rightly say, is produced with the intention of using TYGA's expansion chambers, but very little work needs to be done to modify the manifolds to suit other brands of chamber - it's a minor detail.

Andy.
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