2013 yz450f

24 replies to this topic
  • HRC

Posted April 05, 2013 - 11:26 AM


Why would a engine have to be broken in to start easier? Makes no sense to me.

Makes no sense to me either, but that is a fact.

  • ka24s14am

Posted April 05, 2013 - 11:31 AM


For one, the piston rings will be seated in. More compression, less blow by

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  • Mx Factory USA

Posted April 05, 2013 - 03:39 PM


Run a leak down test on a brand new unstarted engine they kick out 8% valve and ring leakage on average. A fresh broken in engine will kick out around 6%. That 2% is next to no difference. Soooo still makes no sense to me...

Edited by MXpro787, April 05, 2013 - 07:00 PM.

  • Caseihkid

Posted April 05, 2013 - 10:40 PM


I have always wanted too do that on a new engine it makes me wonder

  • WouldsAssassin

Posted April 05, 2013 - 11:09 PM


It doesn't make sense to me either, yet my bike is a LOT easier to start at 20 hours than it was at 2.

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