Cable to transfer turning motion?

[inchpincher]

This is going to be a little hard to describe because i don't know what part i need only the job i need it to do so please bare with me!!!

Ok, what i need is a way of remotely turning a mixture screw (actually an adjustable powerjet) on a scooter carburetor via the headset... I thought about using some model engineers rack and pinion and fabing up a bracket to hold it all (and using just a regular throttle/gear cable) and using a choke lever on the headset but there must be some sort of cable or linking system which will negate the need to transfer a push-pull motion into a turning motion...?

Something like an industrial speedo cable i guess but which has a dial control already nicely fitted at one end?

Need your best lateral thinking please chaps

ta!

 

[brightspark]

use a speedo cable of a motorbike or if u are feeling rich a bias brake cable used on rally car

 

[Tiggy_dorset]

is this setup intended to adjust the fuel/air mixture screw whilst riding the scooter?

 

[wyn]

As Brightspark says, something like a brake bias adjuster cable.

 

[Pete.]

Many motorbikes already have such a cable for adjusting the idle. Some also have it for adjusting the rear shock damping.
Another thing you could use is a control snake for model aircraft.

 

[mr migwire]

alot of exersize bikes have the ratchet dial cable system tha you could adapt to suit your purpose,

just a thought,

 

[inchpincher]

is this setup intended to adjust the fuel/air mixture screw whilst riding the scooter?

Yeah, kind of, but via a powerjet (link) as opposed to the normal mixture screw. I want to experiment using it in conjunction with my Exhaust Gas Temperature gauge so i can adjust the jet on the fly at different altitudes, conditions etc

Like the look of the brake adjuster but it might not be sensitive enough, a quarter turn of the jet is equivalent of upping 2-4 main jet sizes...

Thanks guys,

 

[the snooper]

use a servo motor then all you need is to wire to is a reverse and forward switch

 

[inchpincher]

use a servo motor then all you need is to wire to is a reverse and forward switch

Yeah a servo is what the racers use but more as an on/off function for immediate cooling mid race. Got me thinking though, thanks!

Cheers guys, useful as always...

ben

 

[breezer]

Go on Ben - tell em why you need to do it!

 

[inchpincher]

Ah, sadly this is for when i get back Jim, already dyno'd the scoot without the powerjet so too late in the day to ******ing about with the jetting

For anyone who's curious i'm off on a 3 month road trip around America on a scooter, leave on Wednesday.... Yeeehah!

 

[Dune]

Why do you want to adjust the air mixture screw? This is only used on carbs for low opening running. Other items like the needle, main jet and pilot jet.

Say you where running with half throttle your needle taper and clip position would be the main thing to adjust, 3/4 throttle is part needle and main jet. With WOT just the Main jet. Yes they all contribute but each opening is controlled by one main area.

So adjusting just the air or petrol mixture screw (same thing just depends which side of the ventury it is) would have no affect when at anything over say 1/8th throttle.