Shortening throttle cable with basic tools

mew905

New Member
Sep 24, 2012
647
2
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Moose Jaw
So I spent the last oh... 5 hours trying to figure out how to shorten my melted throttle cable. I bought size 4 Split shot weights, because they slipped into the brake lever hole. As well as a new generic brake line (for the outer sheath). Got home, turns out the split shots are waayyyy too soft to be useful. So I ditched that, and tried to solder (normal rosin core, I cant find silver solder). Solder doesnt stick to the brake line. I was ready to give up... then I thought... what about the small crimp butts? So I came up to my following method that actually works!

Take off your throttle cable, completely, you need to know how much "Draw" you need for the throttle. The RT carb is about 78.5mm long, I havent measured the standard NT carb yet, but the method is the same

Step 1: Measure the cable draw (how long it comes out one end when you pull it all the way)

Step 2: Cut off the throttle nipple, you wont need it

Step 3: cut your throttle outer sheath to the length you want it, the part that enters the throttle grip is crimped on, so you need to cut the other side.

Step 4: measure out your draw length and cut the actual cable at the proper length.

Step 4b (RT carb only) put the carb cable guide on the cable BEFORE putting the new throttle nipple on the cable. Trust me, this will save you a lot of headaches and filing.

step 5: Crimp a 18-24ga. electrical butt crimp onto the end of the cable (the small red ones), take the plastic off however you choose (I melted mine off with a torch). Leaving only the metal crimp.

Step 6: Cut the crimp end to about 5-6mm using side cutters. Slip into throttle slide, and reassemble, and enjoy :)

Successfully shortened my throttle cable to 33 inches using this method. Throttle is snappy again for once. watch the nipple length though, carbs have an area where the nipple can catch and leave your slide sitting high, round it off if you need using pliers or another tool.
 

massdrive

New Member
Oct 3, 2013
454
2
0
Las Vegas
I've made several attempts to shorten the throw on several cables several times and failed. The easiest way I have found to shorten a throttle cable is to take it to a bike shop or motorcycle shop where they make cables. Here in Vegas I go to the Motorcycle Tire Center for all my cable needs. $15 for a new custom cable $5 to $10 to modify an existing cable. By the way the distance the cable extents from the case is called "the throw".
 

Desert Rat

New Member
Jul 30, 2012
565
8
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Apache Junctoin Az
I took a small piece of copper telephone wire wrap it about five turns on end of
cable making sure it's a tight wrap, melt the split shot on stove and dip cable
end in melted lead, has held up for more than 500 miles so far :)
 

mew905

New Member
Sep 24, 2012
647
2
0
Moose Jaw
I do it like this. Works perfectly for me. http://motorbicycling.com/showthread.php?t=9010
Haha, yeah I actually tried that, never thought of melting the split shot on it though being that I dont have silver solder. Didn't work. We have no bike shops around here, only things I could find were motorcycle throttles and they wouldnt sell me any unless I had a bike model that would work, of which I don't know any.

The plan was to cut off the round nub in the throttle handle and use the split shot in there. Didn't hold, so I took an old metal brake lever and tried to use it as a mold. Didn't work either.

It's great there are several ways to do it though, I find mine works the best for me and requires no specialized tools, just a set of crimpers and side cutters, something everyone should have when working on bikes.

I've made several attempts to shorten the throw on several cables several times and failed. The easiest way I have found to shorten a throttle cable is to take it to a bike shop or motorcycle shop where they make cables. Here in Vegas I go to the Motorcycle Tire Center for all my cable needs. $15 for a new custom cable $5 to $10 to modify an existing cable. By the way the distance the cable extents from the case is called "the throw".
Proper terminology is always helpful, thank you. As for shortening the throw, the throw was fine on my cable. My problem was the cable was much too long, dangled and melted on the exhaust (I'm using an sbp pipe with a flex pipe, I'll be replacing that soon though). Now my throttle is nice and snappy, and looks good.
 
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2door

Moderator
Staff member
Sep 15, 2008
16,325
114
63
Littleton, Colorado
Just a word; solder of any kind will not adhere to stainless steel cable. If your cables are stainless you can't solder anything to them.

I feel you are over-thinking this whole process. Shortening a throttle cable is an easy task. Someone suggested wrapping the cable with small gauge wire and soldering. That works but takes a little more labor. I like to use 1/16th I.D, (inside diameter) brass tubing, available at any hobby shop, to make the carburetor cable end. Determine your length, draw or throw and solder a 3/32" long piece of brass tubing to the cable. High temp solder isn't necessary but the cable can't be made of stainless steel.

I see no reason for trying to make the twist grip throttle end of the cable yourself. Almost any bicycle brake cable will work in the throttle 'thimble' the part the cable wraps around, and then you only need to worry about cable length and the length of the draw, or pull distance required by whatever carburetor you're using.

Tom
 

mew905

New Member
Sep 24, 2012
647
2
0
Moose Jaw
Just a word; solder of any kind will not adhere to stainless steel cable. If your cables are stainless you can't solder anything to them.

I feel you are over-thinking this whole process. Shortening a throttle cable is an easy task. Someone suggested wrapping the cable with small gauge wire and soldering. That works but takes a little more labow. I like to use 1/16th I.D, (inside diameter) brass tubing, available at any hobby shop, to make the carburetor cable end. Determine your length, draw or throw and solder a 3/32" long piece of brass tubing to the cable. High temp solder isn't necessary but the cable can't be made of stainless steel.

I see no reason for trying to make the twist grip throttle end of the cable yourself. Almost any bicycle brake cable will work in the throttle 'thimble' the part the cable wraps around, and then you only need to worry about cable length and the length of the draw, or pull distance required by whatever carburetor you're using.

Tom
That's the same thing I thought about the grip end of the cable too, but the brake cable I bought to mess around with... was too big. The end that goes into the grip is slightly smaller diameter than a standard brake cable. I had no idea how to make the carb end nipple, so I figured using a split shot would be easier, hence sizing it out to fit a brake handle. But not only did it not fit, but it wasn't nearly strong enough, so I had no choice but to cut the carb nipple off and shorten it from that end.
 

Goat Herder

Gutter Rider
Apr 28, 2008
6,248
10
38
N.M.
Just a word; solder of any kind will not adhere to stainless steel cable. If your cables are stainless you can't solder anything to them.

Tom
I use silver solder. Any kind of a lead solder just never worked in my travels. Have yet to see a properly soldered cable give away on any of my moped stuff. Just been my throttle cables mostly.

My buddy just lets a drop on the end with no wire wrap at all when he did my throttle cables for me. Forgive me for asking. I must be missing something 2door? Thought mebbe all my cables were some kind of steel. Prolly a percentage is stainless dunno?