Throttle Stop Swap 08 wr250f

i have been looking at these threads for a long while now and they are very very handy  ive got an 08 wr250 and i was wondering if you guys could tell me on a diagram which screw is the actual screw im looking for or maybe pictures of the location of the screw because i dont want to remove the wrong thing. gray wire made the bike a rocket compared to what it had been.  and the exhaust has gotta be flowing better too without the restriction


I don't see it on that diagram but if you take the cover off of the throttle linkage(right side of the carb) it's pretty obvious. It's an allen screw that stops the wheel from turning fully preventing the carb slide from opening all the way.

It is not in the diagram. Many parts are not listed


On some parts diagrams it is listed, though it is not apparent unless you know what you are looking for as it screws in on the air boot side of the carb and works on the throttle wheel (part the inner throttle cables attach too). On the outside of the cab, it looks like a 6mm Allen bolt.

The part number for the one that allows full throttle usage is 5NL-14591-00-00

oh very good thank you guys.  are there any pictures of it anywhere else in the forum that you know of?

and doing the grey wire mod wont hurt the bike in any way will it? motor wise

Gray wire won't hurt a thing, just changes it to YZ map and gives more power.


Remove the throttle linkage cover plate on the right side of the carb (2 allen bolts) and you'll see the allen bolt that stops the throttle wheel from turning all the way, restricting how much the carb slide will lift. Turn the throttle and you'll see it. I've read where others have just shortened the original bolt and put it back in. I think it should be an inch long to match the YZ bolt, but you might want to do a search on that.


okay.   thanks again  are there any differences from the bike pictured in that thread to the 08 that has the different frame etc?

okay.   thanks again  are there any differences from the bike pictured in that thread to the 08 that has the different frame etc?

A lot. But none that are material to the throttle stop. Being able to do it 'on bike' is a matter of the tools you have and your ability to use them.

Do a search for 'LucGallant' (I think that was /is his user name). He did a write up with pictures on an alloy framed bike I beleive.

So, pricing the 5NL-14591-00-00 throttle stop put's it at $20 which seems excessive for a screw.  I would rather not cut down the original screw.


So, what is so special about the YZ screw that it is $20.00?  Why can't one just go to the local h/w store and find a screw with the correct thread pitch, length and diameter and pay a few $$ for it? 


What am I missing here? 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now