I need an internal throttle!

[andy120t]

Internal throttles (twistgrip) ......anyone got one, used one, know where I can find one?  (and I'm thinking old bike stuff, not hugely expensive custom built ones).

I know that old bikes like '40's Indians had these. I also read somewhere online that there are a couple of Hondas that had them but I've certainly never noticed one. So, does anyone know if there are any out there from a factory model?

[flc]

c50/70/90 and some early 70's cb125 twins. there must be more but thats all im sure of.

[K2-K6]

I've also seen them on C90 and seem to recall one on a CD175 twin about 1976 year.

[Bryanj]

Yep to all the above but they are special handlebars to work it

[florence]

The twist grip actions you are thinking of have a slot cut into the handlebars and a shuttle which moves in it.  I imagine your handlebars could be adapted but the slot would have to be very accurate otherwise the throttle would stick.  I don't think it would be worth the trouble for a bike that one would actually want to ride.

The throttle on my Indian was on the left-hand side, with the clutch being operated by foot and a hand gear lever next to the petrol tank; very strange beast to ride.

[andy120t]

I found this diagram online - it's a Honda C90 throttle assembly and shows the slots required in the handlebar. These bars look as if they are square too. I'm going to try & source one to see if I can make it work, but probably be more academic than for real use.

I've previously mocked up one from a piece of copper pipe (in place of a bar) but as it's rather soft & not that easy to work with it ended up being very sticky & not that usable. It gave me some insight into cutting slots in round bar though.

I also found a thread that says these twistgrips only open about 3/4 of the way....so there might be a loss of top-end....or high tick-over.

[Dave M]

I had one on my CB125S and found that you needed 2 handfuls of throttle to get it fully open. It was quite stiff too.

[Yoshi823]

The throttle on my Indian was on the left-hand side, with the clutch being operated by foot and a hand gear lever next to the petrol tank; very strange beast to ride.

Wasn't this called a 'suicide clutch' ?

[florence]

Not sure, but certainly difficult to get used to.  Probably brilliant on those long straight US highways but awkward off-road.