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Discussion Starter #21
DON'T sleeve or bore a factory cylinder. It decreases the water jacket and then it runs hot. If you want a stock bore buy a factory cylinder or check with Millennium Industries or it might be Millennium Technologies. They strip and re-plate factory cylinders. If you want a big bore cylinder get it from Cuervo with the bigger water jacket. If you go big bore you'll also need studs and a SCE head gasket.

FYI, years ago there were a rash of sleeved cylinders that after a few hours of expansion/contractions of dissimilar metals, the sleeve would slip out of position.

Have you checked your cylinder? It may be good! If you want reliability go with factory bore.
Dez you are awesome, you literally have a response for EVERYTHING! I am going to send them my old cylinder. I am trying to cut cost... The work they do seems top notch... Now if i could find a good used head at a decent price, i'd be happy. But ebay is full of heads at almost the price of a new one.
 

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Dez you are awesome, you literally have a response for EVERYTHING! I am going to send them my old cylinder. I am trying to cut cost... The work they do seems top notch... Now if i could find a good used head at a decent price, i'd be happy. But ebay is full of heads at almost the price of a new one.
I have a used head and a used cylinder I could sell. What else do you need?
 

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Looks like detonation damage to me. From low octane, old gas, to much compression. CP pistons don't need any extra machining but the ring gap must be checked. What's your elevation and compression of the piston?
So this was what i though... Pump gas down where i ride my bike is pure shit and excuse my french, it doesnt have an octane rating. The piston was 12:1, altitude is around... 26'
12 to 1 usually requires about 100 octane I believe.
12:1 could probably get away with 91 but the tune has to be on point. My buddies husqvarna 450 has 13:1 and he runs 92 just fine. However with higher octane you could run a more aggressive tune.
 

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Discussion Starter #29
12:1 could probably get away with 91 but the tune has to be on point. My buddies husqvarna 450 has 13:1 and he runs 92 just fine. However with higher octane you could run a more aggressive tune.
No... 12:1 is not for pump gas on the 700, this is why my shit blew up... And not only did it blow up, it took my cylinder and head with it! Don't do it, take an 11:1 piston and get some porting work, add bigger valves and you are all set.

Sent from my GM1910 using Tapatalk
 

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I may be getting older, but I refuse to grow up!
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The design of the raptor 700 head, piston, cam and ignition at 11:1 compression will run on 91 octane without problems. Higher compression may be OK at higher elevations but will require higher octane at sea level. Yes, other design motors can run higher compression at sea level. Example is the YFZ450 at 14:1 on 91 octane.
 

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Smaller bores and combustion chambers can tolerate higher compression ratios. A Raptor is like a single cylinder V8, the large bore is more likely to encounter detonation than a 250 or 450 running the same octane fuel.
 
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