03' WR450 problem after cutting throttle block

I have a new WR450 which I just cut down the throttle block. It gave me more throttle, but now when I reach the top end the bike flattens out or falls on its face. Is it a jetting problem or something else? please help


It's unlikely the jetting would be the problem. Throttle position sensor must now be checked IMO. :)

If not that, disconnect the gray wire.

Good luck.

Thank you Tk421. i disconnected the gray wire but its still the same. As far as the throttle position sensor im not sure what you mean by IMO?


The TPS sensor is in my opinion your problem (IMO).

It is adjustable and can be set up with a Torx wrench and a digital volt/ohm meter.

Check the owner’s manual for the correct ohm readings. There will be two: One for throttle closed and one for wide-open throttle.

Good luck.

He means "In My Opinion" = IMO :D :D :):D :D

What is your jetting?Is it stock :D ? My bike barely ran with the stock jetting and felt weak up top.I tried utvols(sp) jetting recomendations and it has worked out well.

Let us know what your elavation and other area info is.


The Blue One,

Thank you for your input. my jetting is stock, however i am unable to find utvols(sp) jet recomendations. Do you happen to know what the are? :)

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