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07-10-2006, 09:07 PM
This may sound like a stupid question, but I've been out of the four-stroke loop for a while and now just gettin back in it.

Can you bore a 450r cylinder and move up the next size on ther piston? If so..how many bores can you get out of the stock sleeve?

Thanks for any help

R3Concepts
07-10-2006, 11:01 PM
Its NikaSil, so straight bore, No. It needs to be stripped, bored and and re-plated.

The highest I would go on a stock jug is a 98mm, which would be a 490. The 99s break with any kind of high compression.

07-11-2006, 04:00 AM
So how long should the stock bore last being that it is NikaSil? Can you replace the piston and rings with the same size without boreing it to the next size?

I bought a 04 450r that needs some TLC and will probaly be into the motor because one of the cases is damaged. So I definately want to go over everthing and freshin up anything that might be wore while I'm in there?

07-11-2006, 10:05 AM
you should mic the bore to determine if it needs bored.
i've been told that if the cross hatching is no longer visible, you should not put in a new piston.

personally, I would not fool with getting it stripped, bored, and re-plated. It will be just as cheap to buy a new cylinder. I think they are around $200. I would buy a new cylinder and put a higher compression piston in there.