thinking about a WR450

[feallock]

Currently riding/racing YZ250 and thinking of a 450. WR, I like the tranny and elec start...don't like the weight. I did a quick search and couldn't find a "list" of WR mods, any links? My project would be to convert a WR towards YZ. Don't need the lights, would replace exhaust with something lighter, any other weight saving tips. Thanks in advance for info, Mark

[jonova]

Go for it!!!!! Pull of the lights, exhaust and do the cam timing, change the springs, sounds like a lot of work...I would love to have the electric start too. I know there are some guys at FMF that I think have done what you are talking about. Check out Baja Designs too.

[feallock]

Sounds crazy, but I do as much desert riding as I do MX, and since I'm not that fast/big jumper on MX, I'd probably leave suspension stock. Are the 05 WR/YZ spring rates different (front or back?)? Are the cams different? Thought I heard they were just timed different. Until I get the weight down, would tackle the easy stuff first....lights, exhaust, throttle/carb. Is there a "list" of 450 mods somewhere? Thanks again, Mark

[tomwr450f]

WR mods are in this form for the bike, it has help me with my WR.

[jonova]

Sounds crazy, but I do as much desert riding as I do MX, and since I'm not that fast/big jumper on MX, I'd probably leave suspension stock. Are the 05 WR/YZ spring rates different (front or back?)? Are the cams different? Thought I heard they were just timed different. Until I get the weight down, would tackle the easy stuff first....lights, exhaust, throttle/carb. Is there a "list" of 450 mods somewhere? Thanks again, Mark

Mark - I do mostly desert riding and a race when they come up and I changed the rear sping on my WR and will be changing the fronts this summer. The stock WR's are too soft for my riding. The YZ springs are stiffer than the WR's. For spring rates to use I would go to race tech's website and poke around. They also have a spring rate calculator you should utilize.

I'm almost 100% sure that the carb/throttle are the same for the WR and YZ. You will have to re-jet after you do the exhaust and cam timing.

You are correct about the cams. The cams are the same only timed different. Do a search for cam timing in the yamaha forum and you will find some light reading on the subject....

happy hunting ?

[wrkaholic]

I ride an 02 WR426 (YZ timed and tuned) and my son rides an 02 YZ250F. We are trail riders. On the YZ we went down 1 sprocket in the front to get a low first gear for tight trails.

Pros/Cons

1. I have lightened my WR, took off lights, speedo, etc.. went with trail tech computer and YZ plastic. I left the stock tank (I like the range). The YZ is still much lighter. It is still easier to ride in the tight trails, really no comparison.

2. The difference in power between the WR426 (YZ timed) and the YZ 250 is big. I weigh 240 lbs and my son around 180 lbs. The 250 is fun to flick around, but, does not have enough power for me to climb the big sand hills. I still prefer the 426 and in California conditions, power is king with me.

3. Drag Race - YZ is good out of the hole, with a light rider close to the WR, but, runs out of gear around 55 mph. The WR just blows by it. So, if you do any desert riding, you will like the WR gearing better.

Good luck, both bikes are great! - but, don't expect to get the WR as light as the YZ250F. You will feel the difference right when you put your leg over the bike. Get the WR if you want power and desert gearing. The YZ250 will always be easier to manuever and flick around.

For what I like, I would not trade my WR426F for the WR or YZ250F, but, those are my preferences. Others feel different. The terrain you ride makes a big difference.