what to do to improve......wr 450

I ordered a WR450F for endurance beachracing.

I did that because of the benefits in cooling capacity, gearbox, e-start,bigger fuel tank.

My suspension got to be revalved/new springs anyway.

My question now is how to get my engine at the YZ450F level???

Are there any dyno results available of a standard/prepared WR?

Wich are the major differences between wr and yz engine?



What with the jetting specifications?


A lot of questions, i know, but after reading a few posts here i become to be afraid that i made the wrong decision on how easy it was to transform wr into yz horsepower!!!


Search this forum for mods in the last 2 months. Most are easy to find.

Indy, i did, and i find a few things, but still confused about cams and jetting.

What is the exact difference between yz and wr exhaust cam?

Are the inlet cams the same?

What are the differences in jetting?

When i use a motocross pipe do i have to change the airfilter more than just remove the snorkel and baffle?


Hi Aze,

The following mods are pretty easy:

Air box snorkel removed.

Replace the muffler with one of your choice for noise since the European corks are welded on.

Rejet your carb with a standard YZ needle and appropriate jets. This part can be confusing since there are a lot of jets but you can ask racers in your area what jetting they are running. Get a Zip-Ty fuel mixture screw. Dont worry about YZ timing. Ride and have fun!

That exhaust system looks good. If you want more peak horsepower and you are going to buy this system you will need the YZ450 exhaust cam. It should give you 5 extra hp with the cam. You will loose some bottom end but not to bad. Let us know how it goes.

Indy,the exhaust system arrived today!!

For the long straits in beachracing i need maximum peakpower, so the exhaust cam is on my order book.

Now waiting for the the bike to arrive.

This is usefull info, thank you!!

Let us know when you got it all together. I am waiting to get an exhaust system after seeing what works for most of the TT members. :)

Pick up this months motocrossaction mag. It has a real good article in converting the WR to a YZ spec mx bike. Keeping in mind you want the lights and all as a wr the engine mods and setup may help you out here.

Thanks EGO. I have been meaning to pick up that issue. Sounds like a good article.

Thanks ego.

We dont have mxa over here before next week.

Then i'm gonna buy it.

Is the article worth the money???


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