Choke control for stock carb

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Davezilla

New Member
Mar 15, 2014
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San Antonio Texas
Not too hard to do... I got a CNS carb with a cable operated choke and all it is is an older style shifter lever but the cable runs into the carb...

To convert a stock carb like the NT or Speed carb you would need to drill a hole in the choke lever to accept the cable then use a shift lever that could be mounted on the handlebar, stem, or wherever it would be convenient. You'll also need to fabricate a bracket to hold the cable, and maybe loosen up the nut that holds the lever so it can move freely so the cable could push the choke on and pull the choke off. If the cable bends too easily to use a single cable to push on/pull off, or pull on/push off, you could hold the cable straight maybe by hanging a weight to the carb end and tinning the cable with silver solder to make the last few inches of the cable rigid.

Another way to do it which would take a bit more fabrication would be to use a series of bell cranks and a long push/pull rod to a remote lever... This would look really cool if you can do it.

Then there's also the rigid cables used on older lawnmowers that can push or pull to control the throttle or choke... Check out a lawn equipment repair shop in your area and I'm sure they can help you on this method, which may be the easiest of the ones I've mentioned. The only drawback here is that these cables don't like tight bends so the cable will need to be routed in a way to avoid as many bends or turns as possible.
 

mercadion

New Member
Dec 4, 2014
13
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New Mexico
Took a bit of trying but I got it working smoothly. The biggest problem I ran into is I had to make a spring to go on the inside of the air cleaner chamber to move the arm back and forth, there wasnt enough torque from the shifter to do it itself, even with the nut loosened way more than I liked. The counter spring on the outside just takes the stree off the one I made for the inside when pushing it back. I have it set to be pushed into full choke and "tension off" is full open. Instead of trying to drill through the chinese brass I fashioned a loop on the cable and tightened it down.

Definitely a work in progress but itll do for now until I can go for more parts. Eventually Ill upgrade to a CNS but this time of year money is tight and I got tired of reaching down every morning lol.

The holes in the top of the carb was done to give more airflow, and replaced the crap foam with a air conditioner filter from the hardware store, between that an sawing of the pipe on the inside of the muffler cap it made the choke a lot more responsive.



 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Here's a remote choke control I made for my first bike. It worked well but since that one I've found little use for the choke. Occasionally when the outdoor temperature is low I'll use about 1/2 choke but it's easy to reach down and move the lever.

Here's some other ideas and discussion about remote choke controls > http://motorbicycling.com/showthread.php?t=7775

If I could make a suggestion, you might want to reconsider "upgrading to a CNS" carb. It doesn't have many fans here except for those who like to tinker constantly. Your NT will perform just as good, probably better and is trouble free. The CNS is notoriously hard to tune for new builders and offers no real performance increase.

Tom
 

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crassius

Well-Known Member
Sep 30, 2012
4,032
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USA
triumphs used to have a spark retard control that mounted on handle bar - pushed & pulled a bowden cable that you could hook to lever

you might try the cable from a cheap lever type shifter

I have no problems using the heel of my shoe - you should at least try it
 

mercadion

New Member
Dec 4, 2014
13
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0
New Mexico
We get to 10-20 deg here and the choke is a must, other than the initial start (which is getting much easier as the motor breaks in) the bike doesnt complain much about the cold, but certain hills I have to choke it to help it out. Im sure I dont quite have something tuned since I have to do that but Im still figuring it all out. I like the tube you used, I was thinking of doing something similar with swamp cooler 1/4 inch copper feed line.

Good to know on the carb, is there anything past what Ive done to mine I should know?
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
If you need to choke the engine after it gets warm to gain performance that might be an indication of an air (vacuum) leak somewhere downstream of the carburetor. Restricting the air with the choke should cause a decrease in performance, not make it run better.

Check the gasket at the intake manifold where it attaches to the cylinder. The kit supplied gaskets aren't the best quality and often are the source of leaks.

Tom