New WR450 or YZ450FX?

The cams are most likely different to accommodate Estart like on the 250FX

The cams are most likely different to accommodate Estart like on the 250FX

I was thinking of the 450..

Edited by patrick2wd

I was thinking of the 450..

Yeah, exactly. Same deal for both bikes.

I think the cams are milder for the woods bikes compared to the YZ because that's how it's been for years.  If the decomp pin was the only difference they would share the same intake cam.

If you look up the part numbers the FX and WR share the same cam, and the YZ is different.

No one knows yet if the cam grind is different. 

Period.

I really can't wait to read ride reports on the new bikes.  Ive gotten back into riding after I bought my 12 WR450 after several years out of it.  I want to know how the new WR has evolved...  and how much further the FX is from the (uncorked) WR.  I really love my 12 WR but after buying a 250X 2 stroke, Im thirsty for another bike and want to replace or add a 4 stroke.  I almost went orange last bike, but glad blue has some great product to offer.  Lots to look forward to in the WR/FX debate.  The future looks great!

Staight from Yamaha's own literature (this should put the cam profile question to bed once and for all):

Enduro-Tuned YZ450F Power

YZ450F-style 449cc liquid-cooled DOHC four-stroke with four titanium valves and forward intake and rearward exhaust shares the YZ450F’s piston and cam profiles, with WR450F-specific silencer and ECU tuning built for enduro racing.

Staight from Yamaha's own literature (this should put the cam profile question to bed once and for all):

Enduro-Tuned YZ450F Power

YZ450F-style 449cc liquid-cooled DOHC four-stroke with four titanium valves and forward intake and rearward exhaust shares the YZ450F’s piston and cam profiles, with WR450F-specific silencer and ECU tuning built for enduro racing.

 

A cam profile does not include cam timing, or it's relationship to FI or IGN timing.

A cam profile does not include cam timing, or it's relationship to FI or IGN timing.

FI and Ignition timing are controlled by the ECU and have nothing to do with cam timing. You are correct in that the profile has nothing to do with the degreeing of the cam sprocket. The only way to verify that is to measure YZ and WR cams.

In the recent past (06 - 09), the WR and YZ cams had different profiles (06 YZ being by far the most agressive), you could actually see the difference in lift/duration visually. 07 through 09 got progressively milder profiles for a softer initial hit. WR profile was milder yet..

I put the 06 YZ cam in my 2012 WR as it was supposed to provide a substantial incease in power across the range...did not and actually decreased the snap off the bottom so pulled it out and put stock cam back in...much better.

Edited by JDLowrance

as the engines are the "same" and both engines have an e-start, would be logic (??)  to think that the deco would work the same on WR AND YZ

FI and Ignition timing are controlled by the ECU and have nothing to do with cam timing. You are correct in that the profile has nothing to do with the degreeing of the cam sprocket. The only way to verify that is to measure YZ and WR cams.

In the recent past (06 - 09), the WR and YZ cams had different profiles (06 YZ being by far the most agressive), you could actually see the difference in lift/duration visually. 07 through 09 got progressively milder profiles for a softer initial hit. WR profile was milder yet..

I put the 06 YZ cam in my 2012 WR as it was supposed to provide a substantial incease in power across the range...did not and actually decreased the snap off the bottom so pulled it out and put stock cam back in...much better.

 

Yeah, you really have to open the head up to get an accross the board improvement.

I tried the Hot Cams stage with a stage 3 ported head first, and it was much faster, but you could no longer short shift at all.

So I tried the '07 YZ cam and it is fantastic. The torque starts at idle, and you still have a great midrange and great over rev.  Totally flat power delivery.

Still revs 'slow' compared to a Honda or KTM, but that doesn't really matter to me.

The wr has a 5 valve head and the fx has a 4 valve...

The wr has a 5 valve head and the fx has a 4 valve...

No, WR has a 4v head too...

Cams between 16 YZ, YZFX and WR450 are supposed to be the same profiles. The difference would be the decompression pin on the kick start only YZ would be different.

Green sticker... What a load of crock. It's a non issue for 49 of the 50 states yet is made out to be such a big deal in all of the magazines.

 

I agree.   According to the mags, if it doesn't happen in CA, it is not worth reporting.  CA may be big, but it is not bigger than the rest of the world.

I put the 06 YZ cam in my 2012 WR as it was supposed to provide a substantial incease in power across the range...did not and actually decreased the snap off the bottom so pulled it out and put stock cam back in...much better.

 

Which cam did you put in, intake or exhaust or both ?   Did you time it right ?  Are you sure it was an 06 YZ and not a WR cam ?

So if you buy a FX in AZ will it have a green sticker? If you buy a WR in AZ will it still have carb and EPA nonsense?

Does the FX have a radiator overflow catch tank?

No the fx is not green sticker. No overflow catch tank on the fx.

Which cam did you put in, intake or exhaust or both ?   Did you time it right ?  Are you sure it was an 06 YZ and not a WR cam ?

INTAKE

YES

YES

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