Wr/yZ 400/426/450 interchangeable parts

2 replies to this topic
  • rkbdizzer400

Posted June 13, 2014 - 10:44 PM


Hello I have a street legal plated 2000 wr400f former woods racer I'm looking to do a a complete rebuild/supermoto set up I stumbled across a 2001yz426f with a 444cc big bore kit and a blown 4th gear I already have a reliable Drz to ride as a commuter the wr will be a "fun" bike with the occasional track day basicly. What fits what ? And what's the best parts for my intended use like is the wr trans better ? Is the yz trans prone to problems ? Will the yz top end work on the 400 ? Wich forks should I use ? Here are some pics thanks for any help .ImageUploadedByThumper Talk1402728220.617478.jpg ImageUploadedByThumper Talk1402728242.357762.jpg ImageUploadedByThumper Talk1402728281.883111.jpg ImageUploadedByThumper Talk1402728303.965179.jpg

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  • grayracer513

Posted June 15, 2014 - 06:33 AM


The head will fit. The cylinder and piston will fit only if you also use the YZ426 crank.

The YZ trans is close ratio vs. the WR wide ratio, but you can swap the whole assembly in.

Probably just a lot simpler to swap the whole engine assembly. If you do that, you will need to use the WR flywheel and stator, or use the CDI and wiring from the YZ.

The forks are essentially the same except for spring rates and valving. The YZ will be stiffer overall.

  • rkbdizzer400

Posted June 16, 2014 - 02:57 AM


Thanks !! That's exactly what I need to know I agree on swapping the whole engine. Think that's what I'm going to do I just need to decide what trans to use I have a complete yz trans that came with the bike thanks for the help

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