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Piston swap between cbr400 and cbr500?

209 Views 2 Replies 3 Participants Last post by  airhead83
I currently have a 2013 cbr400r - it's pretty much the same engine as the 500, but the stroke is different.

The 400 has a slightly higher rev limit and a slightly higher compression ratio than the 500.

I chanced upon a few threads and websites that mention forged pistons for the 500 that offer a higher compression ratio for the 500s:

Any idea if it is possible to do a direct replacement of my 400's piston to one of these (incl the stock 500 piston) to achieve a higher compression ratio?

P.S. The part numbers for the 400's and 500's pistons and connecting rod assemblies are different, but I am unable to find specific details on what their differences are.
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Without knowing exactly the difference I wouldn't do the swap. It might fit but it can have different weight for example - it will wreack havoc on engine balance. You must be sure at 100% before doing such a thing.
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Parts is parts.... but this seems a bad idea to me.
I can measure and eyeball an air filter or brake pad to see they 'fit', then randomly swap and try.
Not so with internals pieces of an internal combustion engine that's spinning at 9000RPMs when at full throttle.
Unless I could verify, from a reputable engine builder or Honda, that a parts kit is interchangeable.... I wouldn't.
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