Anybody replaced rear brake cable on Radrunner 1?

[handlebar]

From the day my Radrunner arrived, the rear brake creaked, and it felt a little spongy. Eventually, I discovered that the jacket on a section of the cable housing appeared to have been damaged by heat. Touching this section, I could feel the creaky vibrations when I pulled the lever. If the damaged housing could be squeezed shorter, that would explain the spongy feel.

Customer service asked me to document it with a video. A video? I responded with a photo, showing how it looked as if the insulation had been melted by a propane torch. Customer service said they'd send a new cable as soon as they could verify my address. They closed the ticket. I didn't know what that was about. I'd had to provide my serial number and address to open the ticket. In the past three months they'd made at least three shipments to me.

That was 13 months ago. It looks as if Radpower lied to me. So I'll buy a cable. Does anyone know how long it should be? Is there a trick to fishing it through the frame?

[Radding Along]

I know it seems difficult to replace the cable housing, but it really is very easy. I can swap a housing out in about 10 minutes. But I have done it a few times. You can buy long lengths of housing and cut it to whatever length you need.

Tape a string to the original housing and pull it through the frame. Measure up the old housing to the new housing and cut to the desired length. Then tape the new housing to the string and pull it through. Running the new cable through the housing is a breeze. But it will get stuck at the end of the housing. So you need to work it a little bit to pop through the housing.

The only tough part is cutting the housing to the length needed. The housing is made of a steel braided line. It can't be cut with normal lineman's pliers. Or even a hacksaw. You need special cutting pliers to cleanly cut the cable. Park Tool has an awesome tool for that.

Good luck!

[handlebar]

I know it seems difficult to replace the cable housing, but it really is very easy. I can swap a housing out in about 10 minutes. But I have done it a few times. You can buy long lengths of housing and cut it to whatever length you need.

Tape a string to the original housing and pull it through the frame. Measure up the old housing to the new housing and cut to the desired length. Then tape the new housing to the string and pull it through. Running the new cable through the housing is a breeze. But it will get stuck at the end of the housing. So you need to work it a little bit to pop through the housing.

The only tough part is cutting the housing to the length needed. The housing is made of a steel braided line. It can't be cut with normal lineman's pliers. Or even a hacksaw. You need special cutting pliers to cleanly cut the cable. Park Tool has an awesome tool for that.

Good luck!

I hadn't seen your reply when the cable arrived. First I had to unscrew the controller to give the cable room. I decided to snip the crimped end off the brake end of the cable, insert it into the new housing, and tape the two housings together. The cable would keep  them lined up so the new housing would follow the old through the grommets in the down tube.

Old cables were easy to cut and could be soldered to end fittings. I don't have anything hard enough to cut the modern stuff. I gripped the cable near the end fitting with lineman's pliers and bent it back and forth until the strands broke. That was messy. A cut off wheel in an angle grinder did a better job. After that, pulling the new housing went as planned. I used a cut off disk on the new cable, then reamed the end with a drill bit.

I'd thought I'd need a 1.75 M cable. The two cables in the kit were advertised at 1.8 M.  They were too short. I found that they were 1.7 M. I ordered 2.0 M cables, and the first one worked.

There was no more creaking from the cable, but the new one felt even spongier than the old. It occurred to me that the housing had three S bends: where it entered the down tube, where it exited, and near the rear brake. When the lever was pulled, the cable with seek the shortest distance, which could entail compressing spaces in the spiral housing spring at bends. I've been trying to retrain the housing spring by leaving the rear brake lever tied tight to the handle when I'm not riding. It's not as spongy as it was.