How to shorten a throttle cable?

[IOWAracer]

Any one know a way to shorten up a cable an inch or more? The adjustments arn't enough ..not even close. A buddie and I are tryin to put a thumb throttle on a dirtbike. 01 cr125 and the thumb is from a 400ex.

any ideas?

[chadbarger18]

:huh why would you do that
and i dont think there is a way just order a shorter one

[IOWAracer]

He has wrist problems and has a hard time with the twist.... Would any pics help??

[the Z Man]

Try using a thumb throllte cable, I would bet that a 3 or 400ex would work. maybe a 250r if the cable goes in the top of the carb.

[IOWAracer]

Z Man its the 400ex thumb thumb throttle off my old yfz so it has the yfz cable. The end that goes into the carb is too big. So Maybe the 3-400ex cable might work if it has the small end?

[the Z Man]

400ex has a bigger end as well, the 250r has a small end and I think I had a similar problem when I ran a Lectron carb on my 350rx, I think I bought one for a 250r.. I might even still have one laying around.

[IOWAracer]

well how much shorter is it than a 125 cable I wonder? Aslo do you still have that plastic you wanna sell?

[the Z Man]

the 250r is a thumb throttle cable so the pull of the cable is shorter.
I still have the white, missing one front fender, its somewhere at Montezuma, I need a red rear in decent shape.

[IOWAracer]

You said you had a cable layin around? would you send it my way and see if it works and i'll paypal you some cash if it does?

[the Z Man]

lemme check and see...

[wilkin250r]

I've done it, and it worked fine, but it was risky (in my opinion). I don't know if you'll have as much success as I did.


It's a standard Keihin 2-stroke carb, right? The throttle end has a small barrel mounted perpendicular to the cable, and the carb end just has a small cap on the end that fits into the slide?


The carb end is just a small tube that is held to the cable with some sort of solder, and that solder will melt. I had access to a solder pot, but you might be able to use a normal soldering iron, or even a small torch. Heat, and pull the cap with pliers (just gentle pressure, you don't need to rip it off). Once that solder melts, it will pull away pretty easily. If it doesn't pull fairly easily, the solder isn't melted.


Once that cap is loose, you can clip the cable to desired length. The old carpenter's motto applies, measure twice, cut once.

I may have needed to carefully drill my little tube/cap out in order to get it to fit back on, I can't remember. But whatever they used to attach it wasn't normal ordinary electrical solder, because electrical solder won't stick to the steel cable. I used JB weld, it worked for me, but I don't know if you'll see similar luck, but you might.


Now, when I did it, I was careful. I set my throttle stops to make absolutely sure that I never put stress on that cable end. The only stress that cable end ever saw was the slide spring, I was never trying to pull the slide past it's limits. Also, I felt safe trying it because if that end ever DID fail, the slide would close and power would drop. I wouldn't be stuck at WOT.

Like I said, it's risky. It's only JB weld. Like I said, mine held fine. If you attempt it, good luck.

[bwamos]

Originally posted by wilkin250r
But whatever they used to attach it wasn't normal ordinary electrical solder, because electrical solder won't stick to the steel cable. I used JB weld, it worked for me, but I don't know if you'll see similar luck, but you might.

The cable is probably slightly oxidized. Solder wont stick to that at all. You'll need to prep it with some soldering resin (you can get at Radio Shack or the hardware store). Then you should be able to tin the cable just fine. Heat insert and add touchup w/ a little extra solder.

Steel is abit trickier than copper, but if you prep it good it will bind to it just fine.

[KXRida]

If you have a shop close by, take your yfz cable in and match it along some of the bike cables to see if there is a difference. If anything, I'd probably say the twist cable would be longer. No way would I cut a cable, shorten it, and jb weld it back together. If that guy decided to let loose in the woods about 20 miles away, that would be the end of a good day.

[IOWAracer]

We think we may have found a cable that will work but we just need to go pick it up at the shop still have a two week wait because the cylinder needed replated....

[the Z Man]

I will be working in the shop tomorrow, I will look and see if I can find one and bring it to the race..

[IOWAracer]

Bob I wont be at Fort Dodge can you bring it to Duanes?

[the Z Man]

I will try and remember..lol