Whats the differance between a WR400 and a YZ 426

[cooracpro]

I have a chance to pick up a WR400 motor and I was wondering what the differance was between the 2000 yz 426 motor and the 2000 wr 400 motor?Is the wr 400 motor worth 500.00 it looks to be in very good shape,all input will be welcomed.

Thanks Jim

[Doug.]

First off, lets get something straight. A motor is a rotating mechanism that is powered by electricity, and is often found in things like blenders, windshield wipers and garage door opoeners. An engine is a machine that converts fuel into mechanical force. That thing in your Yamaha dirt bike is an engine.

Next, your question. A YZ426F engine will be more powerful, but not necessarily in terms of overall horsepower. The main difference between the two is the power delivery. It is much more smooth and linear in the WRF, which is mainly contributed to its slower cam timing and heavier flywheel effect. If the WR426F engine is in good working order, then yes, I'd spend the money if it is what you're looking for. I would only do it though if your 426 engine is blown to bits. You'll have to modify the WRF engine some if you want it to work like the YZF engine.

And if it's a 2000 WRF, it's a 426...not a 400.

[cooracpro]

Thanks I appreciate your info,I made that mistake with the engine builder for my late model and got the same lecture,guess you could say I was a slow learner.The WR426 engine would be good to have around for a spare.

[Doug.]

The WR426 engine would be good to have around for a spare.

Exactly. And if it's already out of a frame, then I say just adjust the cam timing and maybe put on a lighter flywheel and your looking at YZF power.

[kevin204]

If it's a 2000 it is a WR400. The 426 WR was introduced in 2001. The YZF was made into a 426 in '00 but the WR was not.

[Doug.]

If it's a 2000 it is a WR400. The 426 WR was introduced in 2001. The YZF was made into a 426 in '00 but the WR was not.

Correct, forgot about that. The WRF was a year behind in that respect.