wr450 head (03) on wr400 cylinder

[arnego2]

Hi all

I got a bike from someone to repair a WR400 year 1999 which dropped a valve. After 6 month waiting on parts and the cylinder coming back from PowersealUSA I got most parts and wonder if I can use a WR450 head, with cams and all on the Wr400, the head fits allright but its a tat smaller. about 1cm shorter too. Has anyone done it or tried it?

[FORMA MOTO]

NO

[arnego2]

Well, thanks for the explicit answer Anyone else who tried it?

[grayracer513]

It simply will not fit.

[arnego2]

It fits at least nicely on the cylinder. But thanks if no one did a try I might see if I could make it.

[FORMA MOTO]

It fits at least nicely on the cylinder. But thanks if no one did a try I might see if I could make it.

There is nothing to try!

It's the wrong head.

What else do you need to hear to be convinced?

[grayracer513]

Did you notice it was missing a couple of studs in the head?

I'm not sure why you bothered to ask if you're going to ignore the answers you get.

[arnego2]

I did but if the head of the 450 just needs 4 studs it still could work out with 4 studs IMO. Most likely the cam chain will be too long.

The head is better as the WR400 head as the WR400 did loose a valve.

[FORMA MOTO]

I did but if the head of the 450 just needs 4 studs it still could work out with 4 studs IMO. Most likely the cam chain will be too long.

The head is better as the WR400 head as the WR400 did loose a valve.

All right, this guy is obviously a TROLL, trying to push our buttons.

Either that, or he thinks his WR motor is built like a lawnmower engine.........

IGNORE

[L. Euler]

Go for it. Report back. I have an extra 03 450 head if you need it.

[arnego2]

Thanks I got one already and in quite good shape.

It'll be just a loose trial as I have also to see if I can use the wr400 valves.

[grayracer513]

In a 450 head? No, you can't use 400 valves, either. Looking at the cam chain tunnel, how would you intend to seal it?

The 450 head is "alright" with only four bolts because it sits on a cylinder that was made to work that way. The 400 cylinder won't hold the gasket, even if it actually seals to begin with, with only 4 bolts.