fresh top end break in

3 replies to this topic
  • woodsrider401

Posted April 25, 2014 - 05:08 PM


just finished doing a top end in my 08 450. just curious whos doing what for breaking in the new motor?

  • f150jokerstyle

Posted April 25, 2014 - 10:02 PM


Start it up, check for leaks or anything abnormal. Maybe 5 mins of run time around the yard, check for leaks or anything odd. Load it up and hit the track hard so if it blows up i'm not 40 miles in the middle of no where. Come back home change the oil and filter and clean it all up and then go do a 80+ mile desert race the next day


True story, For a buddy of mine in november we did this. Replaced crank assembly, cylinder, piston assembly, new used head, timing chain, and used all OEM parts and gaskets. Runs as good as new to this day. Break in procedures, break in oils, and junk are to be left to the KTM forums LOL jk well kinda.

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  • Stu2

Posted April 25, 2014 - 10:14 PM


Ya I agree with joker, my engine was totally rebuilt in December, athena bb, new valves, crank, main bearings etc

Did exactly what he mentions and my bike is smooth and strong after 30 hours

  • DGXR

Posted April 29, 2014 - 02:04 PM


After doing a fresh top end, my MMI mechanic runs bikes through two (2) heat-cooldown cycles, each one maybe 5 minutes with light throttle going up and down the street a couple times.  The third cycle he puts a load on it with a handful of WOT runs (avoiding rev limiter), then changes the oil and it's good to go.

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