Thumb Throttle

I'm sure I'll get some negative feedback, but I'm going to put this out there anyway.

I've got an '03 CRF450R. I picked it up used and it's the first bike I've spent any amount of time on. All of my riding prior to this (roughly 20 years) has been on 4 wheelers. With that said, I just can't get used to the twist throttle. This leads me to the idea of installing a thumb throttle with the intent of getting more confortable on the bike.

Any idea if this has been done before?


wow..i am glad i am not the only one!!

i have been running thumb throttle for almost 2 years now on 250F's and a 450 (current ride).

heres what you need.

any honda honda throttle (250r, 300ex, 450r, 400ex)

04 trx450r throttle cable

and a set of atv style grips.

it works great, i have been running it and love it! my buddy recent started (also converted over from quads).

i rode quads for 10 years and also perfered a thumb throttle....

email me if you need more info about it! I currently have mine on a 05 CRF450. Works on all crf's with a FCR carb. if you need more help!

I always wondered that too. It seems like a better system all togther. Twist the entire hand as opposed to just the thumb? Silly. The thumb seems like a much better solution if you take history an convention out of it.

I msut be missing something. They do not use twist throttle stock on quads although some convert to that. Why not twist throttle on a quad? Maybe it has to do with turning the bars and throttle access with a twist? The opposite what is it about a bike tha tmakes it not a good idea? Or is it infact a good idea?

If you put a thumb throttle on your bike, how will you call the quad guys thumbpushers!??

LOL. Someone post some photos! I gotta see this. Whatever feels right to you do it, they always say.

same here post some pics..I have always wanted to see the design in doing this:ride:

eeeeeeew. a thumb throttle.... I can ride all day with a twist throttle, but would get thumb strain in a short time with a push throttle.

Thanks guys for all the feedback. I'll gather up some parts and put it all together.

Are there any tricks to connecting the TRX throttle cable to the CRF carb, or is a direct fit?



its a direct fit, there will be no return cable (the throttle housing has a return spring built in)

To those who say its dumb to run a thumb..i must say, it was the only way i could get away from quads... 1 of the best things i have done to the bike to make the transition easier.

not the best pic, but you get the idea...

you have to move the brake over to the left, but it didnt bother me.. just makes the lever feel like a shorty.


How do you keep a steady throttle in fast choppy terrain or in a whoop section? it seems to me that the bucking of the bars would cause your thumb to jump causing problems.

Thanks for the pic. Looks like I'll have to move the hot start lever back to the left side.


After you install the thumb throttle. Are you going to put on a cup holder. Ice chest rach, and a flag? Ij/k .. well sorta. If you don't like your twist throttle, try a better quality one. They are so much better than the thumb.

Kinda a wierd idea, but being comfortable is what it's all about. Heck I've been putting twist throttles on all my quads for years. I just can't get comfortable with the thumb.

BVC got a gas can to spare?

After you install the thumb throttle. Are you going to put on a cup holder. Ice chest rach, and a flag?

Nope, already have all of those items installed!!:bonk:


Thuimb thnrottle.. if it works for you, great. The important thing is that your riding and having fun.

And I thought I was crazy for rolling my thumb throttle over to a forefinger throttle on my sleds! Whatever works man!!

How do you keep a steady throttle in fast choppy terrain or in a whoop section? it seems to me that the bucking of the bars would cause your thumb to jump causing problems.

its the same exact thing as riding a quad...only your on a bike. i have no issues, im wide open throttle most of the time anyway in the straights, we ride really whooped out sandy tracks..and you have to be wot to keep it tracking in a straight line.

it is easier to stab the gas, and throttle control is a tad harder for some people, because it is more "on or off" than a roll on twist. But i said i rode quads for years and never had issues, and it works for me.

Some of my friends who ride that dont have the best endurance also preferred it over the twist, and claimed they had less arm pump, but only a slightly sore thumb.

I have been curious to try a twist throttle that has less of a turn, my biggest thing is feeling like my arm is moving too far with a twist (call me crazy?), Probably just not used to it.. but for now i'll keep my thumb throttle on it untill i experiment with a diff style twist.


BVC got a gas can to spare?

haha.. yah we had a few at a local "motorsports show" was kind of a joke, just brought a few items that would catch peoples eyes. Ended up being mainly car people, they wernt even into the bikes. Had a few small race car teams ask me if they could have one if i sponsored them......:bonk:

I use a thumb throttle on all of my bikes ktm 200 xc 08,ktm 250 exc 05 ,crf 450r with a rekluse,beta trials 200 ,crf 150,ninja street bike as well love the thumb,lets you pull great hole-shots as well. I ride woods in the A class ,I tell everyone you can laugh at it till you get passed by it.I think it gives more control and lets you ride with the gas on more.I have used this set up for the last 23 years on bikes .

just curious, what throttles are you running on them?

also for your 2-strokes, what throttle and cable did you get to work?

i was going to experiment with a trx250r throttle cable on lets say a cr250 or yz250.

let me know

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