250SX Rear Brake Problem

[Frankencelery]

After doing wheel bearings and differential on my 250SX, the rear brake doesn't return properly. I've read a couple threads that suggest it's the cam that needs to be removed and greased. That makes sense to me.

So I'm planning to take it apart in the next few days, but I wanted to ask two questions for anyone who has done this:

1. In the Honda diagrams, there is an oil seal and dust seal on the cam shaft on the side where the brake lever and cables attach. Is this something I need to replace when I take it apart? I'd rather order and have these things on hand before I take it apart. The machine is rideable, the rear brakes just suck.

2. Should I put any grease on the surface of the cam where it contacts the brake shoes? I was always under the impression that you don't ever want any oil or grease inside the brake drum. I assume it would tend to migrate and end up on the shoes, which is obviously bad, but someone suggested that in one of the threads I read.

Thanks in advance!

[Frankencelery]

Oh, and one more thing...what kind of grease are people using for the cam? I have wheel bearing grease and lithium grease. The lithium is a bit thinner....

[Dirtcrasher]

If you remove the brake cable, is that lever smooth??

Any light grease would be just fine, most people never replace that seal but if you can get one, I'd change it. Keeping water out of an SX is a good thing.....

[225DX DUDE]

I added a spring. Heres a pic.

[Frankencelery]

DC, let me try that when I get home and I'll let you know....

[hublake]

You can get those seals from Honda. I replace them when I had my SX and BR rear brakes apart just as a precaution.

[Dirtcrasher]

Usually the parking brake is the problem, they get used very little and get rough.

I personally remove them from all my trikes because I ride often and can't be bothered dealing with it seizing up.....

The rear brake pedal itself on many models you guys can use orings instead of the stock Honda seals. I like them because I can use them, grease it up and replace them often for short change.

[Sly'85]

I had the same problem with my 250sx and I took it apart and used DuPont Teflon Dry Wax Lubricant. You can use it on your chain as well as it is o-ring safe. My brakes work like new now.

[Name Brand]

Do not use any grease (wheel bearing grease, lithium, etc) on any brake parts ever!

The grease can get thrown or spread onto the braking surfaces and make the brakes not work as well or at all.

Go down to your local parts store (NAPA, Carquest...) and get "brake lubricant". I know that sounds like blinker fluid, but... it's like a grease, but will stay where you put it. It is an anti-seize compound used on all the spots where a brake may need to move. Spread it on the cam, where the springs hook to the shoes and where the shoes pivot and slide against the backing plate. It will keep all the brake parts moving freely and prevent any annoying squeaks. Be sure not to get any of it on the braking surfaces of course.

I'm a big fan of replacing seals, bearings, o-rings, etc when I have something apart. It's a combination of do it right the first time and me being lazy about doing stuff again.

[Frankencelery]

Ok, I took it all apart (except the shaft itself, I don't have that out yet) and the cable needed to be lubed, which I did, and it improved slightly. But even with the cables removed, the lever sticks in one spot and doesn't come back without a little help. It seems like it's the roughness of the surfaces on the brake shoes rather than the shaft itself. The shaft moves freely when the shoes are out. I'll still take it apart and lube it though.

[Frankencelery]

Another update- Pulled out the brake cam shaft and lubed it. Then I noticed that the surfaces of the cam where it contacts the brake shoes, and the matching surfaces on the brake shoes were rusty and corroded. I took the wire wheel to them and it seemed to move more smoothly afterwards. The biggest thing I noticed was grooves on the shoes where they contact the cam. I finally realized that the drum is probably worn to the point where the cam has to be cocked all the time so there's enough travel to apply the brakes, and I think this is another factor causing them to stick.

Knowing a drum is going to be either outrageous in price, difficult to find, or both, I put it all back together. I also replaced the cable return springs, which I had new in stock. This pretty much did the trick! The hand brake now snaps back the way it should. That's the good news. The bad news is that if I have the adjuster tightened enough to give me good braking, they hang up all the time. I had to back off a bit on the hand brake adjuster, and settle for less than perfect stopping power on the hand brake. The foot brake still locks 'em up pretty good, which is helpful, but it always seems like when I'm in a situation where I really need braking power, the foot brake isn't what I'm thinking of.

Ultimately I'm probably going to have to buy a drum and new brake shoes. Sigh. My original wheel bearing project is going to be about $500 by the time I'm done.