I very much doubt that 50cycles would do the throttle mod, if it's my twistgrip mod you mean, and I'm detailing that below. For legal reasons they wouldn't derestrict. If you mean adding a throttle to a bike without one, I don't know how a user could do that, but 50cycles might be able to change an EAF bike to a throttle only one if you ask.
Derestriction and the split mod of an existing throttle are well within anyones capabilities though. I've just given derestriction details on
this posting only today.
The split throttle mod I've detailed on my site
here.
The text there is a bit long winded because I've made the mod reversible, but since no-one ever wants to reverse it, you can look at in a much simpler way.
That is, first free and remove the twistgrip rubber. To do that, you can probe between bar and rubber with a slim screwdriver, add a spot of soapy water and twist the rubber to free it and slide it off. Then remove the insulation around the throttle plug connection, unplug it. Then slacken the allen bolt on the twistgrip and slide it off the bar. Now place the throttle on a level surface and with a hacksaw, cut the handle section exactly in half, keeping the saw perpendiculat to get a straight cut. Discard the outer bit.
Now replace the half twistgrip, also loosening the brake lever and moving that in a bit further, so that both are about an inch further onto the handlebar. Now you need some rubber grips. An easy way to provide the swollen part on the twist section is to bind it with PVC insulating tape back and forth to make a mound, then moisten and slide over a section of the eZee handgrip you removed, cut to the half twistgrip length. Now fit any suitable twistgrip rubber to the outer bar section. The one I'm illustrating below on my Q bike was done in minutes in exactly this way:
The only tricky bit in this is getting off the existing rubber grip. If you use a craft knife to cut off the end cap part first, you'll be able to gently slide a slim screwdriver blade a little way between the rotating plastic sleeve and the grip. Lean the bike away from you a little and trickle in a little drop of soapy water. Rotate the screwdriver either way and the blade will wind around inside the grip and it will suddenly free up. You'll then find it very easy to slide or twist off. Always do that before removing the twistgrip from the bike.
Some users prefer the twisting section a bit shorter, as comfort depends on individual hand sizes. As you see, it's easily altered afterwards if it's needed a bit shorter.
Don't hesitate to ask if you need further help with this.
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