Re-thinking my rear brake.

Thuban
Couple of questions.
What kind of brake shoes did you use? OEM or aftermarket. It could be the linings are so hard they don't create enough friction.
Is the peddle firm or spongy when applying the break?
 
Machine, I put those marks there. It had none. Bike was a one owner, brother-in-law. He was not a mech. All work was done by a shop. Shoes were original Yamaha. It had 14K miles on it when I got it. I think the front and rear tire were original also. ( There around here someplace) Could a shop have gotten the cam in wrong and then I marked it wrong? Yes. But I won't know that until I pull the wheel and for that I'd have to pull the RH peashooter. So I'm going to wait until the rear wheel has to come off to check the cam.
GLJ, Spongy, like your stepping on a big spring. Pretty sure brakes are after market from Mikes. I marked the arm exactly in the spline. I think you can set the arm anywhere you like but that is where everything was when I took it apart. Could be those shoes. I'll cabbage onto an OEM set and I'll have them when needed.
 
Yes, the dimple on the cam looks original, the one on the brake arm was added (by you?). It's assembled wrong, even if that's how it was to begin with. It was wrong to begin with, lol. Like I said, I think many came from the factory put together wrong. Apparently nobody (designers or engineers) told the assembly line guys it had to be installed a certain way, so they just threw them together any which way.
 
Ok, 5Twins, that about makes a consensus. I'll wait until I get the shoes and a day you can't ride and pull it down. I have 2K on these shoes. I'd rather have new ones on hand before I pull it down.
 
Spongy, like your stepping on a big spring.
You might want to look into that. The rear brake is all mechanical linkage. What is flexing to give you the springy feeling?
My XS2 is rear brake challenged. The section of the frame where the brake shaft pivots is not round anymore and the exhaust limits the travel of the pedal to a inch and a half. It works well enough. I think I have Mikes shoes in it.
In a panic stop I think/hope I would revert back to my racing dirt bike days and use the shifter if I needed more rear brakes. Dirt bikes in the early 70s were drum front and back. After a water crossing you had no brakes for a mile or so and only if you made them drag a bit to dry them out.
 
...GLJ, Spongy, like your stepping on a big spring...

You might want to look into that. The rear brake is all mechanical linkage. What is flexing to give you the springy feeling?

Here's a simple test.

Bike on centerstand, stoop down alongside the bike's right side, watch the rear wheel while pressing down on the brake pedal.

If you see the rear wheel rotate backwards a bit with each press of the brake pedal:
That means that the bottom (trailing) shoe is contacting first, at the cam, pulling down on the hub's drum.

If you see the rear wheel rotate forwards a bit with each press of the brake pedal:
That means that the top (leading) shoe is contacting first, at the cam, pulling up on the hub's drum.

When that rear wheel rotation test stops rotating the wheel, then both shoes are making simultaneous initial contact, indicating that they're finally bedded-in...
 
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