--400ex thumb throttle on 250R ??? Will it work???

[TatTooL23]

Need a thumb throttle for an '85 250r. Wondering if any newer thumb throttle will work for fit on the bars and for the cable? Like a 400ex or 300ex or anything like that. Let me know. Thanks.

[Xpress]

I don't see why it wouldn't work, as long as it can pull the throttle cable the same distance.

[Dirtcrasher]

I believe they pull like the 350X, not the leverage pull like the R carb has, it may not raise the slide all the way.....

[Mosh]

No they wont work.
Not without making a custom cable to pull the slide all the way open.
In other words, you need to shorten the steel portion of the cable to pull the R slides open all the way.

[MyMistress86R]

Derrick Adams and I both just went thru trying to figure out this issue. A mutual friend of ours is running one on his TRX and seemed to think he used a CR125 dirtbike throttle cable to make it work. I went about it a slightly different way and actually fabbed a spacer to screw into the throttle housing then screw the stock cable into that for the added length needed to open it all the way. It's slightly complicated but it can be accomplished.