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Discussion Starter · #1 ·
hi i have a question about a gytr piston. i bought it before i had read they had problems with cracking, so im sstuck with it. i bought it for my 08 yfz but im going to get something else for it. the book said it fit from 06 to 08 and would make 13 to 1 compression ratio. My question is will this work in my 04 yfz and what compression would it have. From what i have read it should be auround 13.5 or so. Just need a little help. Ps if it cracks in my old quad it will be ok because i need a excuse to upgrade the crank and do the oil mod.
 

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the 04 and 05's were 439CC motors, 06 to 09 are 449CC motors, i dont believe it will work.
 

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The bore sizes are the same between the years.
Yes it will fit and be 13.5:1

I think they upgraded their GYT-R pistons from the original batch that broke all the time (I know, I had 3 break in my motor and they stopped selling them for a while after that).
 

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Discussion Starter · #5 ·
QUOTE (Ryder25 @ Feb 23 2009, 02:34 PM) index.php?act=findpost&pid=749919
The bore sizes are the same between the years.
Yes it will fit and be 13.5:1

I think they upgraded their GYT-R pistons from the original batch that broke all the time (I know, I had 3 break in my motor and they stopped selling them for a while after that).[/b]
hey thanks but another question can i run 50/50 mix between 110 and 93 with this?
 

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I have had a GYTR piston in mine for a year and a half that was for an 04-05 and I had never had any problems. The only thing different between 04-05 and 06-09 is the crank has a longer stroke(04-05 has 62mm and 06-09 has 63.4mm stroke) that should explain a few things. You should be able to run 50/50 mix or maybe run 75 110/25 93.
 
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