Rear brake squeal and lining gauge reading?

[tml1138]

So I got the GZ250 all ready to go for my wife, and it's running and looking good. BUT, it just started this squealing on the rear brake when you are coming to a near stop. A hard brake it doesn't do it...until you're nearly stopped. Glazing? Normal? Needs look at?

Before I tear into it, I wanted to ask, and a question on reading the gauge on the drum...the manual shows that the lining needs replaced when it's on the opposite side of the range than what mine shows. See pic below. Any input on this? Does it still mean I'm out of lining and need new shoes? Again, I'm not going to be able to get into it tonight and figured I'd ask before I pull the rear wheel off.

Thanks!

[tml1138]

Sorry the image is turned on it's side.

[Water Warrior 2]

That is a common problem with many bikes. Likely the brake lining is glazed from not using the rear brake aggressively now and again to burn off the glazing.
First would be to remove the rear wheel and inspect the lining. Betcha there is lots there but not doing a heck of a lot of actual braking.
The brake drum itself can be cleaned up with emery cloth to remove rust deposits and any glazing that might be there. The shoes themselves can be lightly sand blasted back to new condition. The front pads respond well to the same treatment. A good sanding will do some good if the sand blasting is not an option.

Keep in mind that a previous owner may have moved the arm on the rear drum to get the most from the shoes before replacing them. Not a good plan, and yes I am guilty of that too.
Brake lining and pads(if needed)are cheap when your life is on the line and you need good brakes to avoid something bad.

Give us an update and pics after your inspection.

[raul10141964]

My do it on humid days or after rain at the beginning of the ride, is because rust build up on the drum.
your ware indicator read new pads or almost new.
change the position of the lever do mot affect the reading.
read it when pressing the bakes

[tml1138]

I agree, I would THINK the arm couldn't change the reading (the line on the splined shaft). With the brake depressed, it of course moves further down on the range marking, but still doesn't even hit halfway in the middle.

Maybe I will do a few hard rear brake stops (fortunately I have a long shared private drive to do this rather than take out on the road). See if that cleans off anything. The bike sat for a while unused until I got it, so it could be surface rust. (I know what you mean about rain/rust my little Neon with probably as big of drum brakes as this GZ250 lol, does that until a few stops.)

Thanks for the feedback! I will take pics/give updates, should I need to take the wheel off for inspection.

[Water Warrior 2]

Originally Posted by tml1138

should I need to take the wheel off for inspection.

Yes, the rear wheel needs to be removed to inspect the brake shoes. Remove the brake rod from the rear drum. Back off the chain adjusters and kick the wheel forward after the axle nut is back off. This will allow you to get the chain off the rear sprocket. Now remove the axle and pull the wheel back away from the bike. Be very carefull with any spacers and do not mix them up. Take a pic for your re-assembly to avoid a mix up. I mixed up spacers and destroyed the wheel bearings while out for a ride. You don't want that.
Just pull off the brake hub cover with the lever on it to do the inspection. The innards are really quite simple. Don't loose the springs that hold the shoes in place.
Pics are the best way to keep a record of the way things should fit. Take lots if needed and do your wrenching in a well lighted area if possible.


You will need a new cotter pin when installing the rear wheel. Buy a handfull at a parts store...............you will always need one in the future with every chain adjust.

[spldart]

Just a further bit of data:
Mine was loudly squealing incessantly... So I decided not to check but just order the shoes.
Popped the rear wheel off and r&r'd the shoes along with a deglaze of the drum.
There was a pretty good amount of meat left on the old shoes.
Then no squealing......... but....
I'm now several weeks into the new shoes and it just started, lightly, squealing occasionally.
I guess it's just prone to squeakiness.

[Water Warrior 2]

A little hard braking might keep the glaze burnt off.