YZ Camshaft swap, is my info correct?

Doing the YZ camshaft swap to my '03 WR450 and am trying to source the right parts. Is my info here correct:

2003 WR450

CAMSHAFT ASSY 1 - 5TA-12170-00-00

CAMSHAFT ASSY 2 - 5TJ-12180-20-00 <------ REMOVE THIS

TENSIONER ASSY - 5TA-12210-00-00

TENSIONER BOLT - 95027-06025-00

TENSIONER GASKET - 4FM-12213-00-00

2003 YZ450

2004 YZ450

2005 YZ450

2006 YZ450

CAMSHAFT ASSY 1 - 5TA-12170-00-00

CAMSHAFT ASSY 2 - 5TA-12180-10-00 <------ ADD THIS

TENSIONER ASSY - 5TA-12210-00-00

TENSIONER BOLT - 95027-06025-00

TENSIONER GASKET - 4FM-12213-00-00

If that's right then am I right in thinking that in order to perform a YZ cam swap to an '03 WR all i have to do is source the one part (CAMSHAFT ASSY 1 - 5TA-12180-10-00) from any YZ '03-'06?

Also can anyone confirm if the actual camshafts have their part number marked on them so i can make sure i'm getting the right part. And also which ASSY # relates to the intake and exhaust camshafts?

Anyone?

yes, you'll be fine ordering the 5TA-12180-10-00 camshaft.

If you're ordering new from Yamaha, then it'll come in a box marked with that part number, along with a sealed bag.

Will be buying a used one from a bike breakers. It appears that theres no actual part number on the cams, guy says the exhaust cam i'm buying from him came from an '05 yz450 so will just have to trust him i guess?!

Yes your correct. The YZ, WR, and YFZ all share the same intake cam

The YZ has a different exhaust cam. The WR and YFZ quad share the same exhaust cam.

Most people just do the exhaust cam mod by clocking it 1 tooth different to time it the same as the YZ rather than buying a new cam. Only downside is the TDC mark isn't used anymore to inspect visually.

Yes your correct. The YZ, WR, and YFZ all share the same intake cam

The YZ has a different exhaust cam. The WR and YFZ quad share the same exhaust cam.

Most people just do the exhaust cam mod by clocking it 1 tooth different to time it the same as the YZ rather than buying a new cam. Only downside is the TDC mark isn't used anymore to inspect visually.

Cool, got hold of a cam yesterday that i'm told is from an '05 yz. I guess i can tell it apart from a WR cam by where the timing mark is in relation to the cam profile then?

Also, i'm told that retarding the standard WR cam although does give gains, is not exactly the same as fitting the yz cam as the profile is very slightly different.

Yes to the timing mark.

Its very possible the cam profile is different on the YZ. My WR has a lot mellower powerband than most YZ450's I've rode...

Cool, at least I'll be able to tell if its right before I stick it in the engine. Yours may also feel more mellow because of the head maybe, from what I'm told the yz head has better flow. Also gearing may have an effect, the yz is 4 speed I believe and the 'WR' in WR450 stands for Wide Ratio. Other than that I'm not sure how else the yz engine differs?

The WR does stand for wide ratio instead of the close ratio found in the YZ. The 4 speed YZ was only made 2-3 years starting in '03, then went back to 5.

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