Improving the C model's rear brake

[lonekawgirl]

Hi all! New to the forum, but not to KDX's. I have had a 79 250, a 81 250, 03 KDX220, and still have a couple of 86 C1s, which brings me to my question: How do I make my rear brake perform better? I think when the bike was fairly fresh, the rear brake performed reasonably well. What I think happened, is the brake lining in the hub just got worn out over the years, and now it doesn't matter if I have fresh shoes (and I use EBC) or not....they just don't contact the lining enough to be very efficient. I was wondering if there was a specialty repair shop that could put a fresh lining in the hub, or if there is something else that will help.

[KDXGarage]

Welcome to kdxrider.net.

It might be cheaper to just get another hub or wheel.

[Goofaroo]

Have you put a new brake shoe in the hub to see how it fits the radius? You could use some 60 grit sandpaper and sand the pads to fit the radius. That should speed up the process of them wearing to fit the radius.

Have you sanded the glaze off of the hub? That could make a big difference. Also make sure everything is clean and properly greased including the pedal pivot.

Are your EBC shoes labeled as “Kevlar”? Those are organic and a good choice. Any shoes or pads listed as organic will work best and be more gentle on your disc or drum. They are also less expensive than semi-metallic or ceramic.

Or your hub could be worn beyond the service limit or badly scored from lack of maintenance and metal to metal contact.

[lonekawgirl]

Thanks for the replies. I have replaced the shoes 4 or 5 times over the 35 years that I have owned the bike. Maybe I didn't use the right words to describe the repair that I'm looking for. It's the drum that i am worried about, so I apologize if the original post created any confusion about what i was inquiring about. I'm pretty good about cleaning and prepping the drum lining and making sure the pivots are clean and greased with a high temperature grease, so that shouldn't be part of the problem. What concerns me about getting another wheel assembly or used hub, is that is a definite chance that it would not be in as good a shape as what I have now. That's why I was hoping that somebody had a shop service where they could rebuild the lining of the drum. Factory standard of the drum diameter is 110.00 to 110.16 mm, or 4.331 to 4.337 in. The service limit is 110.75 mm or 4.360 in.. I haven't checked the actual inside diameter yet, but will do so, the next time it quits raining and we have a sunny day here.

[Goofaroo]

It might be possible for a machine shop to fix it but first you need to measure it and see where you stand.

I’ve often wondered on my XR and my 87 KDX what I would do once the hub is worn out. One option would be a disc brake conversion but a decent machine shop might be able to sleeve it.

[lonekawgirl]

I would love to do a conversion to my C1. Have often thought it wouldn't be too difficult, because the rear wheel assembly on my 220 looked like it would easily fit my C1, and with a little fabrication, the foot pedal and the master cylinder looked like it might work nicely too. I always look on Ebay for rear wheel assemblies for the H models, but they are very scarce, these days.

[KDXGarage]

I would be a dollar the hub is beyond spec.

The price to get it repaired would be a lot more than just trying again with a used hub and having your rim, spokes and needles moved over with new bearings.

It ain't cheap, but you got 35 years out of it.

Get a 1989 - 1994 KDX200 rear wheel and rear brake setup. Four brackets as best I remember:

one for pedal
one for pedl height adjustment
one for master cylinder mount
one for reservoir mount

additional 3 mm wider washer that is OEM from 87 or 89?? (can't remember which one)

Also, caliper mounting plate needs to be modified (the piece that fits over the rear axle.

Buy once, cry once. :-0

COOL bike! Glad you have had it that long!!

[lonekawgirl]

additional 3 mm wider washer that is OEM from 87 or 89?? (can't remember which one)



COOL bike! Glad you have had it that long!!

Thanks for the information.
Probably the 89, since the 87 would be identical to the 86.


I think the bike is pretty cool.

[Thebeast]

Just a thought, but You may able to modify the shoe pins to compensate for drum wear...
Or find a brake shop and have thicker material glued to a bare shoe..

[lonekawgirl]

Just a thought, but You may able to modify the shoe pins to compensate for drum wear...
Or find a brake shop and have thicker material glued to a bare shoe..

Interesting option.

[targetman]

I too would like to find a a way to fix the C model rear hubs. The problem is there are no good used ones out there. I scrapped one that was grooved pretty bad, and now wish that I would have saved it. Not interested in a disk break conversion.