Clunk noise when using rear brake

[leenaqvi]

I had a friend put new tires on my GZ250. After putting the rear wheel back on the the arm that engages the brake (the brake cam lever) was pointing straight up instead of straight down. He took off just the brake cam lever and rotated it 180 degrees to make it point down. After everything was put back together when I first pressed hard on the rear brake there was a loud clunk and then the brake engaged. Now every once in a while there is a clunk when applying the rear brake. Does anyone have an idea what the problem could be? I am suspecting that the rotating of the brake cam lever might have caused a problem? Unfortunately that friend is no longer around and my mechanical skills are limited.

brake cam lever.jpg

[blaine]

Trying to wrap my mind around what did but it needs to come back apart & assembled correctly.....Changing just the brake arm would not fix the original problem......If anything make it worse........If the back wheel happens to lock up when you on the road your gonna have a major problem.

[Water Warrior 2]

It may be a good thing that your friend is no longer around to help you. Swapping parts to a different location can be VERY life threatening. Get it fixed by a Pro and be safe. To my way of thinking the brakes are the most important system on the bike.

Just a thought. If the wheel spacers were not reinstalled correctly then there could be a side load on the bearings on one side or both and are ready to self destruct. The clunk could be a warning sign that only shows up under braking. If that is the case then find a real mechanic and have the bearing replaced and get the brake sorted out.

[spldart]

I've had a rear brake grenade on southwest freeway Houston Texas.
Broken brake shoes and everything...
Get the service manual and assemble correctly please!
And use good parts... A defective shoe caused my incident.

Edit:
Oh! And mine was clunking before the incident which broke several parts.

[leenaqvi]

Thanks for the replies. Just to be clear there was nothing wrong with the brake before we took it apart to put on the tires. He just rotated the brake arm to be pointed down instead of up. I don't seem to be getting the clunk anymore, and the brake is working, but I think I better take it apart and check it out anyway.

[blaine]

Originally Posted by leenaqvi

Thanks for the replies. Just to be clear there was nothing wrong with the brake before we took it apart to put on the tires. He just rotated the brake arm to be pointed down instead of up. I don't seem to be getting the clunk anymore, and the brake is working, but I think I better take it apart and check it out anyway.

I'm not sure I understand.......The arm is supposed to point down??????

[Water Warrior 2]

The arm should be pointing down.

It just occured to me that the arm was rotated during the R/R for the tire replacement. The arm should be removed and placed in it's original position on it's shaft. Then the entire arm and shaft can be rotated into a downward position as designed for proper operation. That will allow for proper clearance of other parts and places to get hung up.

[leenaqvi]

Yes the arm was moved to down position as in the picture in the my first post. However to move it to the down position it was removed from the brake housing and them rotated to the down position. The clunk has really only happened when I was testing the rear brake, so I was braking hard at a fairly low speed. The link below talks about this kind of clunk being common from hard braking on rear wheel. I don't normally use only the rear brake. I was just testing it after the tires were changed and since it made a clunk I was testing again with hard rear braking to see if the clunk would come back.

http://www.r6messagenet.com/forums/r...ar-brakes.html

[spldart]

So...
1) You need a tire installed
2) Friend installs it
3) The 'brake cam lever' is facing up not down... Was the brake cable attached at this moment???
4) The 'brake cam lever' was removed from the 'brake cam shaft' and reinstalled roughly where it should be.
5) It's still clunking

A) what condition were your brake shoes in?
B) That clunk can be very dangerous as each time it happens it puts a nasty shock through the brake components.
C) The friend re-installed the wheel with brake lever up?!?! No more help from that friend. Please. Before you die.

[Water Warrior 2]

Originally Posted by leenaqvi

Yes the arm was moved to down position as in the picture in the my first post. However to move it to the down position it was removed from the brake housing and them rotated to the down position. The clunk has really only happened when I was testing the rear brake, so I was braking hard at a fairly low speed. The link below talks about this kind of clunk being common from hard braking on rear wheel. I don't normally use only the rear brake. I was just testing it after the tires were changed and since it made a clunk I was testing again with hard rear braking to see if the clunk would come back.

http://www.r6messagenet.com/forums/r...ar-brakes.html

Little to none of this link has much to do with your situation. Just put your bike back together the way it is supposed to be. Then you can be sure nothing odd is in the mix. Make sure there is a small spring attached to the ends of the brake shoes to keep them pulled up against the cam when the brakes are not being used. This keeps them in their proper position and ready to use. I have a feeling the spring has gone AWOL during the rear wheel removal. Take pics of your procedure so we can see first hand what is going on. We can help you with the job and talk you through anything you don't understand. Most of us have been there done that in our riding careers. We learn through experience and great folks willing to share their knowledge. There are no dumb questions, if you are unsure of something, no matter how trivial, we can help.

By the way, please learn to use both brakes to their maximum. Practice emergency braking so you know what to expect when things get dicey.