Advice on first 4t top end.

2 replies to this topic
  • irishmatt18

Posted April 23, 2015 - 10:11 AM


I am going to attempt redoing the top end on my 2010 450t. 


I have never done one before and I am getting an OEM kit as well as a timing chain to replace while I am at it. I have done 2 strokes before but I am a little nervous. 


Any tips and tricks? Any advice?

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  • G-BRO

Posted April 23, 2015 - 10:46 AM


There are a lot of good threads and websites out there. Keep in mind that most are not from professional mechanics. I did my first one 2 years ago. You will probably make a few mistakes (hopefully minor). Take your time, keep logs, stay organized and pay attention to detail. I took a lot of pictures for reference as well. Ask the TT community or your local mechanic on specifics as they arise. Make sure you have a manual in hand before starting. Spend the money on the CORRECT speciality tools. Correct size ball hone brush, feeler gauges, micrometer, flywheel puller, valve spring compressor etc. If you are planning to tear down another 4t in the future these tools are worth the investment.

I really liked this url when I was building my 426 -


I liked the builders style and overall view.

At last, but not least, when in doubt ask Grayracer for help!!

Edited by G-BRO, April 23, 2015 - 10:46 AM.

  • MxSkater86

Posted April 24, 2015 - 10:43 AM


Tear down is pretty simple, just more components then a 2 stroke. Re-assembly is obviously the hard part. Make sure you get a torque wrench for the Head bolts and the Cam caps. They are the most critical ones to torque down. Also triple check that your cams are timed correctly and that your valve buckets and shims are seated fully (ran into a leaking valve because a shim was not seated correctly).


4 strokes aren't really that hard once you do 1 or 2, but it will make you enjoy working on a 2 stroke again lol

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