13.5:1 and Hotcams

4 replies to this topic
  • JDLowrance

Posted April 08, 2009 - 10:53 AM


I am going to install a JE 13.5:1 piston and Hotcams in my 08 YZ450F which is being used for supermoto. Got a package deal I just couldn't pass up.

Just want to check with the collective to make sure I'm not going to run into any piston / valve interference issues or anything else I should be concerned about.

Anyone install this combo? Impressions?

Thanks in advance, John

  • stevenacarter77

Posted April 08, 2009 - 11:45 AM


only issue i can think of is all the $$$$$$$ your gona spend on raceing fuel

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  • KJ790

Posted April 08, 2009 - 11:53 AM


There shouldn't be any interference problems, and depending on your elevation 93 pump gas should be fine to run in it.

  • wondermuscle

Posted April 08, 2009 - 01:51 PM


There won't be any clearance issues.

Let us know how it turns out! :thumbsup:

Also, update the jetting database if you change that to help others who want to mod.

  • TIG88

Posted April 08, 2009 - 03:33 PM


Many people run 13.5:1 without race gas. You may have to run it if your at sea level from what I understand.

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