I have seen cases where a manufacture reproduces a part if demand is high enough, but for the most part they want you to buy their new products. Don't count on Honda reproducing a crank for the NSR. 21/28 cranks should be available for several more years though.
The cranks can be fixed, or even made from scratch, but currently the cost is about twice that of a new crank, if not more.
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james
Its not how fast you go...Its how you go fast.
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