Convert thumb throttle to half twist

[fifthmass]

Hi,

Was transporting my bike in back of car this morning when I was (very) lightly rear ended by another car. The impact jarred my bike in the trunk. Got out, yelled at bimbo to pay attention, saw no immediate damage to car or bike and went on. Turns out the only damage was the thumb tab on my throttle broke off leaving a wonderful sharp stub. Was able to get from parking area to work but really glad for gloves with leather over the thumb.

Has anyone on these boards ever converted a thumb throttle to a 1/2 twist? I imagine it could be done with a short length of PVC and some epoxy. If so how well did it work? Thanks for any feedback.

regards,
Bill

 

[FMB42]

What brand/type of controller/throttle are you running?

E-bikekit has a full twist "hall effect" (IIRC) throttle on sale for $8USD.

http://www.e-bikekit.com/shop/index.php?p=product&id=17&parent=16

 

[fifthmass]

It's the Crystalyte 40A 48volt model. Don't know the actual details (analog/digital, etc) beyond that (i should... ). It was the current controller model as of November of 2008.

The one at ebikekit.com sure is a great price. Need more detail regarding the connector. If it's compatible with the controller, that would be the way to go.

regards,
Bill

 

[dogman dan]

I have no idea how buried the thread on it is, but the conversion is childishly simple.

Cut a piece of 1" pvc pipe about an inch or inch and a half long. Glue to the throttle. Use pvc cement sparingly, so you don't glue the throttle so it can't rotate. That's it. If you have some old shifter parts laying around, the inner part of the grip shifter makes a nice sleeve to go between the bars and the pipe. If not, just a scrap of flat thin plastic will do. The pipe is just slightly oversize.

 

[Lock]

When I snapped off the lever on my thumb accelerator it left a stub that I just filed smooth. There was enough stub left that I could still use my thumb, but also have the option of wrapping my hand over it comfortably to use as a twist... I find being to alternate means less soreness from longer trips
tks
loCk

 

[fifthmass]

I have no idea how buried the thread on it is, but the conversion is childishly simple.

Cut a piece of 1" pvc pipe about an inch or inch and a half long. Glue to the throttle. Use pvc cement sparingly, so you don't glue the throttle so it can't rotate. That's it. If you have some old shifter parts laying around, the inner part of the grip shifter makes a nice sleeve to go between the bars and the pipe. If not, just a scrap of flat thin plastic will do. The pipe is just slightly oversize.

Thanks Dogman,

I have some scraps of PVC available. Will cut a notch in the edge to slip over the stub of the thumb throttle.

regards,
Bill

 

[slowlane]

Might be good to note full throotle can be hacksawed to 1.0" measured on grip not the bevel. Discovered they pop off easily under power and go full speed because magnet has left the sensor on brushed drive.

 

[fifthmass]

OK got it done! Could not get anything less than a full length of 1" PVC so bought a 3/4" PVC coupling and used that. Was same outer diameter as 1" PVC. Solvent welded the end to the rotating bevel part of the thumb throttle. Let it cure and went for 30 mile ride.

Results: Did not snap off, was WAY more comfortable than a thumb throttle with no numbness in the thumb or tingling in the back of my hand. Won't ever go back to a thumb unit now. Actually there is no reason why you could not add on the PVC sleeve to a functioning thumb throttle and have a throttle that works fine either way. Would be good for reducing throttle fatigue by having two ways to use it.

Bill