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Discussion Starter · #1 ·
I have an bone stock 06 that I just got and the motor is destroyed. Got it for next to nothing and now I need to rebuild. I have been lurking on this site trying to gather all the info I can but still have a few questions. (thanks to all who's post I've read) I tore the motor down to see exactly what I have. The lower rod bearing seized on the crank and put a side load on the piston which I guess you can say scored the cylinder. What I need to know is if I can hone the cylinder with out any issues with the chrome. I think the marks are just from the skirt rubbing the rings look undamaged and if thats the case I should be able to get the aluminum off.

I know I need a new piston and crank but Im unsure what to get. I want to go high comp and stroke it, but I want some life out of the motor. I will be getting a pipe and air box for it and what ever else I need to get the most from it. Since I have next to nothing in to buying it I don't mind throwing a few bucks in to it. Let me know what you guys think.
 

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Discussion Starter · #3 ·
I have a good idea of the parts I want but need to know more about cleaning up the cylinder wall. Ill post some pics of the damage to see what you think.
 

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Please support your site sponsors....

i blow away the prices posted above on any of those parts...

if you look in the sponsor section , i have a sale on CW jugs for $210.

i sell the stroker cranks to members for $270... and support the site!


as for your cylinder... i wouldnt use it if there is ANY scoring at all.... not worth the problems in the future.
 

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Discussion Starter · #6 ·
heres a pic of the piston I cannot fid any damage to the rings.


Below are pics of the cylinder. its more of a smudge of aluminum than a score in the cylinder.


 

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Don't risk it....
 

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If nothing else, get it honed and checked. You could probably pick up a cylinder if you post in the wanted area. The problem is even if the cylinder "looks" ok, it could start chipping the coating off later. That being the case, you could end up with problems down the road.
 

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I'd say, for sure, replace the piston. The scarring on the piston skirt is actually from debris getting between the piston and the cylinder meaning, you more than like have metal shavings in your motor.

Since your doing a crank, just go through the motor. Check the oil pickup and, make sure that isn't clogged. Also, clean out the oil tank and, clean the screen inside the oil tank.

I'd also recommend a new cylinder. You'd probably get away with deglazing it but, take it from me, do it right the first time or, it'll cost you more later.
 

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I wouldnt reuse that cylinder. I just picked up a new cylinder from the yamaha dealer for $190. It cost more than that to re nikisil it
 

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Discussion Starter · #12 ·
I won't mess with it then and just get a new oem. now for the piston is the gytr high comp any good?
 

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I think everyone here has given you great advise, but I havent seen anything mentioned about doing the oil mod, I would either do the old style mod why your case is split, or get with J&T and do the 07 mod. If you end up going with a strocker crank though you might want to do the old style (depending on which piston you use), There has been issue's with the piston on the stroker, contacting the squirter on the 07 mod!!! JMO..
 
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