2003 450 exc (Canadian)

Can someone explain what the term "restricted" means? I just purchased a new 2003 450exc and was wondering if there is something that needs to be removed or changed.


I was thinking the same thing... in my manual it mentions a throttle stop... which the MXC & SX versions don`t have.

Do we have to grind it like they do on the Yamaha WR`s ???

I think that it is refering to the jetting being so lean. Resticted intake for California emissions

So the burning question is: Do I need to do anything to my bike other then change the needle out with the one that came in the kit? BTW this is also the same needle that the manual has stated. I put the clip in the same position. Will the bike run okay?


The resrticted models are actually Australian spec bikes. There are a few floating around in Canada. I think most of them have gone to the US though. The "restricted" bikes have a throttle stop like the US WRs have and a screen in the muffler that needs to be removed to achieve max hp. They are jetted even leaner than the "G" models, if that is possible, from what I understand also.

So how do I figure out if my bike has the throttle stop and screen in the muffler?


Pull the carb off and look at the slip with the throttle WFO. If it's not open to the top you have a T stop and if you have one you more than likely have the other.

Did the bike come with signals and all the dual sport stuff? If it didnt, your bike is NOT the restricted models. CDN spec bikes are exactly the same as the bikes you guys get in the USA.

Hope I can clarify some misconceptions out there on the Can Model. It is exactly the same as the American model. That being said there are a few Aussie/Euro model, floating around Canada, and I was fortunate to get one.

The difference is the Australian version comes with full signals, horn, high/low beam, indicators, mirrors, and front and back break lights, and a different sub fender to accomodate the larger tail light.

The restrictors on carb are totally different than YZWR models. The 03 carb is a new model FCR and the throttle stop is inside the slide, it only allows the slide to move 1/4 throttle, limiting RPM to about 3800. The air box has a shroud and baffle which completely covers the filter. The exhaust has a wire mess screen spark arrester visable in the muffler.

The bike also comes with a replacement needle which is the same as the off road version. The air box baffle is removable, and the screen can be cut out if you wish. With all the restrictors in place the bike is 82 db. This was obviouse done to make some legislators happy, but it can all be changed in a hour or so. Hope this answered some questions on the Canadian version.

So I waqs also fortunate to get the Aussie model - is it restricted too? I did not see any covers on the air filter box, did not see a screen unless it is way inside the exchaust and by turning the throttle it seems that it opens all the way up. It did come with another needle which I have replaced. So what is up?

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