One last gramlin to wrangle, rear brake kick back?

Hey guys, my bike is almost complete. I took it for a quick spin today and noticed when I apply my rear brake, it damn near locks up and kicks the brake pedal back up really hard. Any ideas what could cause this? Thanks guys, much appreciated.

 

Did you have the brake apart and check for delamination? Or is this happening with new parts?

Did you read this? http://xjbikes.com/Forums/viewtopic/t=15874.html

 

Well it didn't do it before, but I took the rear wheel off and now that it's back on it's started to do it. I guess I will yank it off tomorrow and have a look, I just find it puzzling that it just started doing it after working perfectly fine.

 

Use a Dremel Tool and a Medium Sanding Drum and remove the Rust Ridge on the Brake Drum.
Just remove the Rust; not a lot of the Drum.

Examine the Brake Shoes.

Some aftermarket Brake Shoes have the Brake Material on Shoes ... such that there is a LEADING and TRAILING Shoe.

 

Thanks Rick, I will try that tomorrow.

 

Just curious... You did bolt the retainer arm back on to the bottom of the drum cover, right?

 

Well it's a custom hardtail, so I fabricated a bracket to hold it in place, hopefully that isn't the problem, I really don't want to have to grind it off.

 

Well, the reason I brought it up is that there's really no way for the rear brake to kick back on an XJ. The only way that can happen is if the drum cover spins (even a little) when you apply the brake.

 

I have a feeling that, like Putin, the delamination monster is rearing its ugly head.

 

or if a brake shoe is flopping around inside the drum...

 

This would definitely cause major lock-up issues, but I don't see how this would make the pedal physically kick back.

 

Well I took the brake apart, there is no delamination and the pads are well above the 2mm my Clymer said is the minimum. The only thing else I can think of is somehow the bracket isn't working. I gotta run and take a Math exam, when I get back I'll take a pic for you guys to see, maybe my bracket or linkage is not working and I'm just overlooking it.

 

If the problem persists:

Remove the Brake Shoes.
Place them Side by Side.
L@@K at the Brake Shoe Brake Material.

Is it "Balanced"?
Is the Braking Material --> Equidistant to BOTH Ends.
If they are ... they are Late Model Shoes and cannot be installed incorrectly.

Or ---
Is the Braking Material --> Offset with a GREATER Amount of Brake Material closer to one end.

If the Brake Material IS "Offset" ... The Shoes are LEADING and TRAILING Shoes.
Some aftermarket Suppliers still make LEADING and TRAILING Shoes.

 

Thanks for the info Rick, but they worked fine before, it's just since I chopped the old hardtail off and made a new one.

Here are some pics for you guys, please excuse the ugly welds.

Rear Linkage and Bracket


Front Linkage


Whole Setup

 

The only potential problem I see is the bolt that keeps the cover from rotating... Even a little wobble would allow the cover to turn when you apply the brakes.

Step on the rear brake, and rock the bike back and forth. Watch the drum cover...

(looks very nice though!)