| Whats all this "up to 53bhp" including a 620 and putting 675cc and 583cc bikes together, there are big differences, 620s rev harder and can extract more speed from there gearing, 675's make more low down power than a 583 and can pull slightly higer gearing allowing them to extract more speed.
And if anybody thinks that suspension tweeks can make up for a 10bhp disadvantage at Snetterton they must be on something. | 
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