'99 wr400 engine swap?

4 replies to this topic
  • dickm

Posted March 29, 2009 - 07:18 PM


'99 wr400 went goofy today; sounded like the decomp lever was held on while driving 55 mph-; stopped immediately; no compression, kicks easily around. O.K. I've done a search or two and can't find an answer to.

1. should I look for A 426 engine to swap out?will newer engines/426/450 fit

2. a cheap 426/yz/ to pirate parts/motor for the plated 400

3. spend money for current motor repair.

4. find a cheap Monster and fab a Monstro on the cheap

I'm in no hurry, all my money goes towards kids braces and a Ducati habit

  • tweeter

Posted March 30, 2009 - 03:02 PM


There has to be a reason why the bike has no compresion. Pull the valve cover and inspect the exhaust cam. This only take twenty minutes or so. Most likley the decompression device is stuck.

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  • dickm

Posted March 31, 2009 - 06:30 PM


thanks tweeter, the noise,etc sounds like what you describe. I'm ready to toss it off a cliff otherwise. Except for there's not too many cliffs here in Seattle where I wouldn't get caught for littering

  • pablo83

Posted April 10, 2009 - 11:40 AM


If it's just a stuck decomp lever you're looking at about $250 in parts (cam, bucket, shim) and not much labor, so I wouldn't throw it off a cliff yet. The 426 takes a different jug, piston and crank (con-rod). I thing everything else is the same. The mounting bolts line up so you could just replace the entire engine if that's what you wanted to do. I don't know anything about the 450.

  • Middy01

Posted April 12, 2009 - 01:43 PM


Chuck it over a cliff to me :p I'll take it..


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