How much does a lightened flywheel improve perfomance and is it realy worth the money?

Not much, and it depends!! :)

If you want really sharp throttle response, then the lightened flywheel is for you, or if you just have to have every available extra, then it's for you!

Ultimately, with less weight to spin, the crank can get on with its' job of turning reciprocal motion (up-down of the pistons) into rotational motion and spin the clutch/transmission, but as a consequence of this, less weight means a loss of inertia on inclines and a therefore a slight drop in torque.

If you're racing you probably want it!

Andy.
NSR-WORLD.COM

I was going to post a seperate story but this posting has prompted me to reply now. I have a road going NSR and I purchased a lightened flywheel last year, I did not notice that much improvement as I road along. The biggest improvement was in my mind( I must be quicker 'cos I have a lightened flywheel) Over the last 3 months my bike has steadily got worse it is now at the point of only running on tickover. I sent my bike in to a specialist to try and resolve my probs, New HT leads and carb tuning + a strip down and rebuild did not cure my malady. It was suggested that my loom or TPS or PGM could be the culprit. I fitted new carbs with TPS no change, I fitted a new loom, no change, I tried a new air box, no change I tried a new PGM, still no change. I fitted new plugs...........wow the bike will now rev! I blipped the throttle to warm up the motor and BANG! something went wrong. On stripping things down I discovered the the flywheel outer face had parted company with the cam. I have a new standard unit on its was and hope to fit it this weekend. I am also hoping the this broken flywheel has been the root cause of my on going dilema. I have spent a considerable sum of money so far in elininating one prob after another. A big thank you must go out to Mr Nigel Moss for loaning me several components for me try fit and try before I went ahead and purchased them. Thank also to Andy for his help and support........I was soooooo near to jacking it all in and buying a 4stroke. So..... Dont use one unless yoy really have to.
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Hmmmmm!

I guess Mr Honda did his research well, and the road bike got exactly what it needed - and no more.

Remember that the NSR was launched to win races, so they were pretty well thought out bits of kit.
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