Throttle cable

http://motorbicycling.com/f39/norm-shortening-throttle-cable-9010.html

These cables are bone dry outa the kit - lube it up good and check it and the cable routing - making sure it's all gentle curves w/o binding

Look up normans post on shortening throttle cable. His post makes it look easy, and it is(have done several myself).

Your handle bars painted or chrome plated? If they are painted sand off the paint or just enough
paint so the throttle sleeve spins freely on the bars where the plastic throttle sleeve covers the handle bars. The paint can be on there thick enough to make the
plastic throttle sleeve bind on the handle bars or smooth the painted area with 400 wet/dry sand paper to get rid of any high spots that make the throttle sleeve bind.
graphite dry lube or graphite speedometer cable lube will helps slick up that area and should not attract as much dirt oil or grease.

I like Norm's video and he makes it look easy ,but I'm sure it would work i've silver soldered many times but I don't want my soldering prowess to fail and be the cause of a damaged engine so I didn't like the standard cable length that came with my kit 'I've found none of the guys I ride with do ether.So this is what I came up with, it does the cutting on the hand grip side of the cable and starts with a bead I turned on my lathe

Next get de-railer teflon lined cable housing from the BS and a long de-railer cable(if you want to make a really long one for ape-hangers) you will have to grind the end so it will fit into the carb cable adjuster and the slide, or just take the throttle off and measure the length of the cable sticking out from the threaded end to the outside of the bead (write this number down you will need it later)cut it next to the bead and remove it, then put your new cable housing on your bike running it just how you want it to be (without the cable inside)and cut it,take a file and cleanup the ends and install the little caps crimp them on (sta-con pliers work good). Next you insert the cable in the carb end and assemble your carb just like it runs, with the noodle no the end just like it was when you measured before now it is sticking out pull it tight make sure all the ends are seated read the measurement from before and cut the cable. Now take the bead you made(or scored for a bud)and slide it on your cable and using a pair of needle nose hold it flush with the end of the cable, a little dab of flux and solder with an acid core solder I use a propane torch, let it cool clean it up with a file and reassemble and you now have a smooth acting correct length throttle cable. I know the bead thing is a drag , but it is reusable if you put it together and don't like it you can change it. Hope this helps Later Bob

My cable was also too long,but after a while the end broke off at my throttle,so im using a brake lever for throttle and also took the chance to shorten the cable at the throttle end,i cut off over a foot of housing and cable,im using a caliper brake end bolt with hole threw it with nut on the end of cable on the brake lever, its been working great for a long time.

I've shortened bicycle type cables several times and have done so on my recent build. The easiest way for me is to measure the exposed length of the inner cable when pulled all the way out (disconnected from the bike). Then I cut off the twist grip end right next to the ferrule. I use a brass or steel bolt with a shank about the same diameter as the cut off ferrule and drill a hole sideways through it to fit the cable. Once that's drilled I cut off the bolt on either side of the hole to make it a barrel shape the same size and length of the original ferrule. Then it's just a matter of soldering the new ferrule to the cable maintaining the same amount of free cable sticking out of the end of the outer housing. I also solder them on with a propane torch and 60/40 lead/tin solder using soldering flux. Dip the end of the cable into the flux, push it through the ferrule and heat them up with a propane torch until the solder will melt and flow into the joint when touched to the metal. Don't hit the solder directly with the torch, just heat the metal until the solder will suck into the joint. If it balks, dab some more flux on the assembly and try again. Once the ferrule is soldered clean it up thoroughly to remove all traces of flux which can cause corrosion. Dress up the ferrule with a small file if the solder got sloppy and you're in business. I made up a set of brake cables for my ultralight aircraft and flew the airplane for over ten years without ever having a cable end part, and there were times when I was pressing on those heel brakes pretty hard!

This may help also....
SHORTING YOUR INNER CABLE ? how do you know how much to cut off ?