WR450 Kick Starter locked after Rebuild

Hey guys, this is more for documents sake.


2003 WR450F 55,000 Km's


rebuilt the top end of the bike after PO had jumped a tooth, destroyed the impeller, ruined all intake valves, and i think the cause was probably the problem I'm having now.

Seems the crank bearings are shot, couldn't budge the kick starter, and starter motor wouldn't work either, starter motor was seized so when i had the stator cover off gave the starter a few taps while pressing the start button on and off quick, got it going, still didn't work. The catch is, i can turn the crank by hand (breaker bar on the nut) and it feels a bit stiff, and hard in some spots. New piston a rings in. goes up and down all good


After some research i found it could be one of the following:


1. Kick starter gear jammed (Screw or piece of metal in between the gears)

2. Stator catching on the flywheel/magneto thing.

3. Clutch catching on the cover (too many clutch plates or too thick)

4. Piston hitting valves (bad timing or jumped a few teeth), or Piston rings not seated and jamming.

5. Something obstructing con rod (One guy had a piece of his piston skirt break off and jam it)

6. Seized or bad bearings on the crank (Pretty sure this is my problem)


Well i went through 1-5 this afternoon. all are good, i will need to take the head and bore off (Again!) and see if there is still friction or stiffness. I'm hoping that's the problem as the other problem is the bearings, and i really cant be bothered haha. but might as well rebuild the bottom end while I'm at it.


I will post up my progress when i get to it, but i am heading back to NZ for 3 months due to a family crisis so will be putting the bike on hold for now.


If you have anything else you can think of to check, please post it up as I'm still learning also, and its good to share info





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