Ok, I'm just about finished restoring my "Pretty In Pink" 86' GT Pro Freestyle Tour. Just have to hook up the brakes! I've always run gyro's, even bitd. I never even owned a rotor! So I'm a little stumped on the one that came stock on my bike. I'm assuming the rear brake cable first attached through the top of the stem and tightened at the bolt just underneath the stem (which would be the bolt attached to the top of the rotor) Then I assume there should be a cable sticking out of the bottom half of the rotor which would then run to the rear brake. Am I right so far?? Ok, my problem is there is no cable coming from the bottom of the rotor, I'm guessing the previous owner may have cut it? Is there any way to take the rotor apart to replace the cable? Or is it too much of a pain in the arse to deal with? Is that a hard cable to find? Sorry for the long winded post. Just wanted to be clear on my problem. Thanks.

If it's a first gen rotor, then I'm not sure if there is an easy way to take it apart. Later models had a hole in the top covered with a plastic cap. I believe that if you pop the plastic cap off then line up the top and bottom holes then you can feed a new cable through. Your local bike shop or even walmart maybe should have replacement cables that have a brake lever fitting at one end and a different fitting at the other. I think it's for gear shifters or something. That's the end that you want to keep. Cut off brake lever end and feed it through.
See the picture below. Keep the end piece on the left and cut off the end piece on the right...




Does your upper headset cup have a cable stop like this?

This will give you the gist of the setup...

It should be a snap ring holding the rotor together on the bottom. Just remove the snap ring and disaseble the rotor and install the new cable.

some of the mid-gen rotors used a threaded collar on the bottom, in place of the snap ring.

But you don't actually have to go through the trouble of disassembling if it has the hole in the top piece right?

right. as long as there is a hole in the top piece, you just line up the holes in the top, bottom and the bushing in between and slide the cable thru.

if there is no hole then you have to disassemble the whole thing, whether it's a snap-ring style or threaded style.

Thanks for the help guys!...Pauly, Yes. My upper cup is exactly like the one pictured. And my rotor does have the removeable cap on the upper half. As soon as I saw the replies I went to work! This is actually a really cool design. I never appreciated it before because so many of my friends bitd who ran rotors hated them because they didn't like the breaking power. And as soon as gyro's came out (in 86' I believe?) everyone switched. Anyway, whoever thought of this design did a really great job. Very simple to hook up once I read the replies here. My only problem now is that my brake lever is tight as hell, lol. The rear caliper won't even squeeze in? Any ideas on what I did wrong? One thing I noticed that I did differently was the way I positioned the upper cup with the tab directly in front of the headtube, so that the tab is right in the middle, directly under the hole in the stem. Could that cause it to not be able to squeeze the lever in? When I had the cups pressed in I never even thought of positioning the tab to the side. Once I saw the pic on here it just looks like it makes more sense as far as cable routing. I guess that's what I get for rushing, lol. But someone please tell me that I don't have to re-position the upper cup

Far too much friction going on in the cables, or else the center brake bolt is too tight. Take the cable off, take the inner cable out of the sleeve, and lube that baby up. Many of us use white lithium, but there's been post after post on what kinda grease to use.. everyone has their favorite. Anyhoo.. after you grease up the cables, and reassemble, check the tension on the rear brake.. don't over tighten the lower nut! It also helps if you take apart and grease up the caliper, pretty much all points of friction, including the corners where the spring ends slip into. Reassemble, and you should be good go go. Also, grease up the stem shaft, where the rotor slides. I, as well as a lot of us on here have dialed in Rotors to work just as good as a Gyro.. it just takes time and patience. You can do it! Don't get discouraged! Frustration is all part of the fun.. you'll be throwing tools across the driveway like it's 1986 all over again, in no time :-) Even better to do this kind of stuff outside at this time of year.. get the red, chapped, painful hands.. instant memory, LOL. Pain.. brings it all back ;-)

Thanks Sunburn. But while reading your reply I think I figured out what the problem is. I have my stem slammed downagainst the rotor, so there is no way for it to "slide" as u mentioned. Am I supposed to just pull the stem up a little then tighten it? If that's the case then won't my headset eventually loosen up? Making sure the stem was always tightened all the way down was my fail-safe against the headset loosening, lol. It never dawned on me that the rotor had to slide up and down, lol. Let me know if I'm correct as far as just raising my stem up a little, Thanks! And sorry for my rotor ignorance, lol.

You use your stem as a headset lock? LOL... interesting idea, but you can't do that with a rotor. Yes, you need sufficient shaft exposed for it to slide. Lube the shaft too. (I can't believe I just said that.)

The rotors I have used seem to work better if you have the top and bottom cable lined up directly over/under each other.

LOL. Yea, it's worked well for me for years! I tighten the headset down and then slam the stem down and tighten it. Never had a problem with a headset loosening up. But you're right, I can't believe I didn't think about the rotor needing room to slide up and down. U know how hard it's going to be for me to come to grips with the idea of lifting my stem up after all these years?! LOL. I guess now I'm going to have to invest in a locking headset!...Oh yea, the shaft has been well lubed my friend, lol. I think I even heard some Barry White playing in the background... ...

LMAO. If you do that too much, it will affect your bunnyhopping skills.

But yeah, dude.. the rotor needs room to operate, up and down. Also, make sure there is no slack in the top cable, when you're dialing it in. pull that !@#$! as tight as you can, with the rotor in the DOWN position, because if you pull it tight in the up position, lol.. where will it go, when you pull the brake lever?

You don't need a headset lock, that would just take up space. Hook up a Tioga Beartrap headset, they are readily available on ebay or wherever. If your headset is in good shape, you wouldnt need to replace the cups either (PIA) just the parts.

I cant think of anything worse than the extra friction a dry shaft can cause. It can help to have friend check that you have the correct lube amount by getting them to look under it while you hold it up......

well thats my handy hint for the day. I think I'll head over to the cafe' and tell some fart jokes.

Gonna hook it up tonight! I wonder if plumbers tape would work for keeping the headset tight? Anyone ever try that?

i always used 2 drops of red loctite in the top nut, evenly spaced. it's enough to keep it tight, but not so much that you can't break it loose when needed.

Great tip! Thanks...Unfortunately I decided to just take the rotor off and not use one at all. But I did have it working great! I just couldn't stand having my shaft exposed ...Seriously though, If I ever come across an old school gyro then I'll throw that on. But to be honest, I'm really not going to be whipping the bike around anyway. The few simple tricks I do won't even require a rotor/gyro at all. I'll take some pics of it and post them tomm night or Sunday. Thanks again guys for all your help!