Author Topic: Full lenth to quarter length twist grip modification.  (Read 7222 times)

Offline Leslie

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Full lenth to quarter length twist grip modification.
« on: August 09, 2010, 12:37:23 PM »
For safety purposes. 

Im sure the EU CE folk will now make 1000 laws about this if the see this post.

I cut my full length hand throttle into a quarter hand length throttle, and butted it with the end off another hand grip.



If the throttle pulls off in your hand, being previously damaged by numerous means, while in use, the motor can get stuck at full speed compounded by the fact you can lose one hand on the handle bars for controlling the bike. This can be a very dangerous situation. Some people, like my self, can ride at times single handed on their bikes.

Im not sure how the new full hand throttles compare to the old gm full throttle.  My full hand throttle pulled off just lifting the bike up as it lay on the ground by using the full throttle.


All that needs to happen is the bike falls and or receives a nasty impact, and this puts shock onto the full twist grip, causing damage to the plastic tabs that holds the grip into the throttle chassis, and the twist grip can pull off in your hand anytime after this..

After the above mod was applied to a broken throttle that the twist grip was broken to the point it didnt even stay onto its fixture, always sliding off , and that broken throttle still lasted for years with this mod.

I cut every full throttle I buy now and mod it to a quarter hand length throttle, default mod I say.

Leave 3.5 CM on the twist grip after the cut, maybe more to make sure there is room for error so you can work the edge is square and smooth, and make some slippy washers from some hard plastic to go between the butt and twist grip, smooth the twist grip edge where it is cut, set it up so the butt cant pushed too hard against the twist grip, and it works the charm.

This is the throttle mod I speak of explained in MSpaint.





Bring it on

Offline Sundsvall

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Re: Full lenth to quarter length twist grip modification.
« Reply #1 on: August 09, 2010, 07:02:23 PM »
I think this appears to be a good idea, but is the throttle on the picture GM? If I cut the GM throttle and then realize I shouldn’t, there probably will be difficult to purchase a new.

I can’t see the MS Paint drawing.

Peter
« Last Edit: August 09, 2010, 10:37:43 PM by 317537 »
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Offline Leslie

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Re: Full lenth to quarter length twist grip modification.
« Reply #2 on: August 09, 2010, 10:37:59 PM »
I think this appears to be a good idea, but is the throttle on the picture GM? If I cut the GM throttle and then realize I shouldn’t, there probably will be difficult to purchase a new.

I can’t see the MS Paint drawing.

Peter

These were the old GM throttles.

If you want to do this.  Get or make the slippy washers first and the hand grip butt and then you have all the parts you need, this is honestly the hardest part, I cut my throttle with a knife it was so easy.  You can cut the twist almost 1cm to the chassis but its a pain in the hand to operate.  3.5 CM left on the throttle is good.

Most if not all throttles can be cut like this.  As the hall sensor is inside the throttle chassis and there is no risk damaging the magnet inside the twist grip that operates the hall sensor.

The cut must be very straight and smooth.  You must adjust throttle position along the handle bars so there is no chance of friction between twist grip and butt.  The butt must sit against the handle bar end so it can not slide towards the twist grip to cause friction on the twist grip.

The butt must be solid on the handle bars and not slip off easy.  You can buy good butts at the bike shop for the twist shifter gears.

Once you have all these things considered the mod is fail proof.

As for the MSpaint pic, here ya!




The photo you see is of my throttle that was broken.  When it came off in my hand the wheel started going full speed.  lucky the bike was on laying on the ground at the time  I manages to put it back on and thought id fixed it..

On the way home it came off again in my hand and the bike got stuck full speed while riding and I nearly lost control.  I kept trying to put it on when riding home, it was very awkward to say the least.

LOL a Ebiker riding at full speed with a broken twist grip in hand, waving it around, trying to stick it back on.  You get the imagery here?

I got home did some research and managed to fix it like you see in the photo.  I never had a problem again.  The broken modded throttle was indeed stronger than a the brand new one.

I could pick my heavy SLA bike off the ground with the throttle and it never ever came off again.
« Last Edit: August 10, 2010, 02:13:51 AM by 317537 »

Bring it on