High compression piston

2 replies to this topic
  • Yzflier977

Posted January 06, 2013 - 01:36 PM


Hello all, I'm new to the world of 4 strokes, but so far I absolutely love my 450. I have a 2009 yz450 that I bought used last summer. Previous owner says it had around 40-50 hours on the bike, and he was selling it because it was just too much power for his tastes. I've put 25 hours on it according to the hour meter since last July and I want to go ahead and refresh the top end and do a cam chain swap as well. I'd like a little more bottom end punch and have already put a '06 CDI on it as well as a 50 tooth rear sprocket. I have been contemplating the Wiseco PK1363 13.0:1 compression kit. I have some questions about switching to a high compression piston including, will I still be able to run 93 octane pump gas without any issues with detonation. Also what are the advantages/disadvantages of running a high compression versus a stock piston? And will it give me a little more bottom end snap? Any info is appreciated.

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  • DC_Excitement

Posted January 06, 2013 - 04:49 PM


what do you have for an exhaust?

  • Yzflier977

Posted January 08, 2013 - 06:17 PM


Stock exhaust, but I've gone in and removed the "snow cones" inside the can and repacked it. I wanted a freer flowing exhaust while at the same time retaining the stock shorty look. Big improvement and it definitely helped the snap a lot.

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