First time rebuilding 426...any advice?

3 replies to this topic
  • wizze

Posted November 09, 2004 - 10:30 AM


I've decided to attempt rebuilding the top end on my 00 426. Since this is my 1st thumper (bought it used this year and never rebuilt), I figure it will be a learning experience. Just hopefully not an expensive one! Are there any tips, tricks, advice or anything I should be aware of before I dig in? The manual looks pretty straight forward but sometimes they assume you know things that you don't.

  • ThumpDave

Posted November 09, 2004 - 07:33 PM


guess not sorry dude I'm not qualified to help.

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  • MXbob60

Posted November 09, 2004 - 10:39 PM


Just finished a top end on my '01, and was suprised at how easy the job was. Follow the manual, make sure the bike is CLEAN, take your time, keep the parts you take off the bike organized, use a torque wrench, and you should have no problems. You should have the bike done in about 4 beers :cry:

  • jespertheil

Posted November 09, 2004 - 11:24 PM


Like said, first make sure that the bike is clean like a hospital!!! You don´t want any dirt falling in there!
Take it step by step, but first read the manuel a lot of times till it´s almost in your head. :cry:
Things to watch out for:
When you get the valve cover off, rotate the engine till it you reach the TD center. That´s the small line you can see trough the hole in the iginition cover. There is also a small H, but you must use the small "I" dot..
Then you will see that on the cams there will be 4 small dots that should on a vertical line.(almost)
Now you have taken the presure off the cams because the valves are closed.

Now remove the camtensioner as showed in the book.
Now you can losen the cam bolts a little at the time each.
When you take the cams up be careful that you don´t drop the sliders they are placed on, they might fall all the way down in the crank case.
Don´t min the chain, you can pull it up again no problem.
Make sure that you place the things together in the right order as you take it out.

Now you can loosen all the bolts holding the top.
Getting the top out can be tricky with the engine still in the frame. First remove the right camchain slider. Then lift the top 1 inch and then you can take the other slider up too. then slide it out on the right side of the bike.

Losen the cylinder and slowly take it up too.

Putting it together can be quite a job by alone, so have a friend to help you with that. It´s so much easier with 4 hands.. :cry:
especialy when installing the piston in the cylinder again, that can be difficult. Just make sure that the rings are mountet correctly..

Just write if you need to know something.
Good luck. :cry:

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