want to buy a new 2013 yz450 or 2013 wr450, need advice

[grayracer513]

There are at least 3 WR's competing at the Expert level in my local desert races; two EFI bikes, and an '08.  The guys on the '08 and one of the newer ones are in the top ten in their classes all the time, and they guy riding the '13 is not a very big person.  As a desert racer, I'd give the latest WR's a very serious look. 

[Navaho6]

One other thing, not sure if its significant... the WR engine has a longer stroke, 95mm versus 90mm.  Its also pretty stall resistant, so you don't have to deal with things like this.

https://www.thumpertalk.com/topic/1101326-a-relluse-clutch-or-weighted-flywheel-to-prevent-stalling/

 

However, Yamaha isn't the only one to make bikes that stall.  Many KTM450XC owners add flywheel weights and fudge with various things to improve stall resistance. 

 

I agree that the WR is more stall resistant than the YZ.  That is one thing I really liked more about the WR.

 

I think the WR would be a great woods bike if you strip it down like MidlifeCrisisGuy has done AND get the suspension revalved.  If you can get the WR close to 240 dry WITH all the stuff you would want for offroad (hand guards, radiator guards, stabiilzer, skid plate, kick stand), that would be a very impressive WR.   I did the math and there was still a 10 lb difference between the YZ and WR with all things being equal.  Some of that is in the FI system.

 

No matter which route you go, YZ or WR, you will thin your wallet and have to spend a lot of time with your tools.  I personally think that the newer WR has a better chassis than the older YZ's.  It turns good yet is very stable.

 

My decision to sell the '13 WR and get a YZ was based on cost and laziness.  I just didn't feel like spending the time on the WR when I had a chance to buy a really good YZ that was already built and had the best suspension I'd ever ridden. 

[grayracer513]

One other thing, not sure if its significant... the WR engine has a longer stroke, 95mm versus 90mm. 

 

The bore and stroke of the current WR450 and all earlier models is the same 95 x 63.4mm as all the Gen1 and Gen2 450's were, including the '03-'09 YZ450F's.  The new Gen3 ('10+ YZ450) engine is 97 x 60.8.  The reason WR's stall less it that they come with a significantly heavier flywheel already, heavier in fact than anything you can buy for a YZ, and in stock form, they have a lower first gear and less aggressive valve timing.

[DTM Industries]

Wow these are alot of great input and advice ! Thank you everyone !

[MidlifeCrisisGuy]

Some quick updates in case anyone comes to this thread thinking about a WR for hard core use.

 

1) I installed an 08 YZ exhaust cam.   The bike rocks with it.   Better pull everywhere, better lugging, it never stalls, smoother, runs cooler, etc.  For reasons unclear to me, the 08 intake cam had clearance issues.  With the cam, I think this is the best woods engine you can buy, period.   And I'm still running the stock comp ECU map, all zeros, so there is room for further improvement.

 

The YZ cam reduces the engine braking quite a bit.   Makes control much easier in slick conditions.   On/off throttle transitions aren't nearly as abrupt.

 

2) I updated the TCs to 22mm.  Stock was 25mm.  Used 2010 YZ450F TCs. $150 on ebay.  Had to bore the upper fork tube holes out 2mm to 56mm.  Everything else is bolt on.   This dramatically changed the feel and steering of the bike.  My friend thought it was lighter.   The weight didn't change, it just turns way better. 

 

3) I'm doing the suspension now.   The WR shock is a 46mm unit with the 16mm shaft.   All the usually YZ parts are interchangeable, including the shock body.   One thing to note... the 2012+ WRs use a special compression adjuster assembly.  The ports on the WR piston are 2.3mm, versus 2.8mm or 3mm on the traditional KYB adjusters.   The small ports make the WR shock harsh on roots, ruts, etc. at speed.  Its a simple process to drill them out or use a YZ piston with the larger ports.  It is my opinion that no amount of special valving or whatever in the rest of the shock will fix this.  It must be addressed directly.   If your suspension tuner tells you they don't touch the compression adjuster, find another tuner.

 

I have 2 suspension threads (shock and fork) over in the suspension forum. 

 

A few more "hard core" details...

 

A lot of people talk about need Rekluses on these bikes.  I'm running a 9.5mm Magura clutch and with C1 adjusted, the 08 exhaust cam and the KX cold start knob mod, this thing is basically unstallable.    And if it does stall, 1 kick usually gets it going.  About the only time I ever stall it is when I'm loafing along and I go over a log too slow in 2nd gear, when I should be in first.

 

The newer WRs (2012+) have faster primary gearing than the old ones.  Take this into account when selecting your sprockets.  If you don't need the top speed, don't be afraid to gear the bike down, especially with the cam.   Makes 2nd and 3rd gear much more usable.  With 12/51 gearing, my bike loves technical terrain.

 

Stock WR450Fs are good bikes, but nothing to write home about.  However, with a little work they can become absolutely awesome.

Edited October 2, 2014 by MidlifeCrisisGuy

[grayracer513]

The newer WRs (2012+) have faster primary gearing than the old ones. 

 

Unless you mean "older than '05", no, they don't.  It's the same 2.652:1 ratio as every other WR/YZ450F made from '05 onward.  Same two gears.

[MidlifeCrisisGuy]

Unless you mean "older than '05", no, they don't.  It's the same 2.652:1 ratio as every other WR/YZ450F made from '05 onward.  Same two gears.

 

======================================================================

         Primary ratio           drive gear pn      driven gear pn             Ratio

2005 WRF    62:22    5TJ-16111-00-00    5XD-16150-20-00        2.818

2013 WRF    61:23    2S2-16111-60-00    5XD-16150-60-00       2.652

 

I'll leave you sort out the YZ ratios.

 

Edited October 2, 2014 by MidlifeCrisisGuy

[grayracer513]

My bad.  Once again,  the WR lags a year back of the YZ450.  The Primary ratio that was installed in the '05 YZ450 was transferred to the WR450 in '06, not '05.  But it has been the same ever since.

 

You should also know that this change had nothing to do with gearing the bike itself higher overall.  The purpose was to reduce the torque load applied to the clutch and transmission by going to a lower numerical primary ratio.  On both bikes, the change was made up for by a one tooth change at the front sprocket, resulting in nearly the same overall reduction ratio in any given gear.