# .40 on a 660?



## JLOWERY (Jan 30, 2010)

Does anyone know what .40 on a 660 makes it on CC's? I think it makes it a 686 but I'm not real familiar with the Yamaha's


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## brute574 (Aug 10, 2011)

686 is 102mm bore.


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## JLOWERY (Jan 30, 2010)

So how does that compare to .40 over


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## Waddaman (Oct 3, 2010)

Convert .4 to mm then find the stock bore and stroke of a 660. Then with your new bore times it by the stroke.


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## JLOWERY (Jan 30, 2010)

100mm is standard 101 is .40 over


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## JLOWERY (Jan 30, 2010)

It's a 674


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