Rear brake shoe plate not flush, dragging

[Rlauchard]

Hi all,

Got the girl running and moving with a chain, front brakes are working again, almost there.

I noticed when pushing the bike in neutral, there was a 'drag' coming from the rear wheel.

I got down and saw that the brake shoe plate is dragging on the front of the bike (right side if you are looking directly at it) and a couple of millimetres off of the back (left side looking directly at it). Attached is a pic from the back of the bike...you can see the gap close as it moves up and forward.

I had to do some bending of the tension bar due to an unintentional bend (oops), and I'm thinking it's putting pressure on the plate and pushing it 'in' towards the bike...

Am I thinking about this right, and need to take off the tension bar, adjust and try again until the plate is flush?

Thanks for the help.

 

[5twins]

I guess that could be the problem. I see the brake plate torque arm in your pic and your "custom" bend. That's definitely wrong. Try assembling without the torque arm connected to see if it comes out straight. If it does, bend and fit up the arm while the wheel is installed so it fits correctly.

 

[Rlauchard]

Thanks....so...nope and nope...the torque arm didn't force it in.

I assume that the brake plate and the 'brake shoe housing' have to have some gap. Why am I assuming that? because the brake plate doesn't move and the wheel does...and metal on metal would seem to a) cause things to slow down (wheel revolutions) and b) cause things to get pretty damn hot.

So..if I have good spacing (maybe, again, I don't know what the spacing should be) on one side and not on the other...then, I can only think of a couple things on my own.

1. I'm using the lines on the swingarm to 'tighten and align' the rear wheel/chain. So, if the swingarm was bent or isn't as it should be from previous owner, perhaps that could pull things awry? [I loosened up the chain puller on the right side of the bike, and it seemed to give some reprieve to the part that was 'grinding']

2. I have a bent hub, or I have a bent brake plate...that seems strange because they both appear to be pretty solid. [This brake plate was on my stock 16" mag wheel, and I swapped it into an 18" rear spoke hub/wheel.]

3. I don't have the brake plate mounted into/onto the brake shoe housing correctly. I didn't see a right or wrong. Since it spins, it seems to just fit.

Thoughts?

 

[5twins]

If the hub was bent, the gap would change positions as you turned the wheel. Does it? I think you may have bent the brake plate with your "custom" torque arm mods. If that is the case, I would mount the brake plate in the wheel off the bike with the axle and added spacers (so you can make the assembly tight. Then I would whack the high side of the plate with a big rubber mallet to see if I could bend it back straight.

 

[Rlauchard]

Thanks 5twins....

I haven't ridden with the torque arm...and I didn't modify it while it was on. That being said...a couple of questions.

1. Is there supposed to be a gap between the housing and the plate? I assume that there is...if so, do you know roughly how wide of a gap, so that I can see if anything is correct?

2. Do you have a pic of a not modified 81 torque arm?

 

[5twins]

Yes, there should be a small space between the brake plate and hub, maybe 1/16", but it should be equal all the way around. Something is definitely bent on yours. No pic of the Special torque arm, just the parts drawing. It is offset at one end, the front, and from the looks of your pic, you may have it on backwards ......

 

[XSLeo]

Another thing, when tightening the rear axle, it's a good idea to press and hold the rear brake before you tighten the axle. Now hold the brake as you tighten the axle. This centers the brake plate and shoes in the drum. Doing this makes the shoes hit the drum evenly and at the same time. maximizes contact between shoes and drum.
This may or may help with your issue.
I might pull the wheel and be sure the shoes are fully seated on the brake plate as well as look for any obstructions that may be between the plate and hub. A chunk of dirt can do what you describe.
Leo

 

[XSLeo]

Just had another thought. You might want to look at the axle. It could be bent right where it passes through the brake plate. Not enough to bind as it slides through but maybe enough to tip the brake plate.
Leo

 

[jayel]

a couple of things,
1st the lines on the swing arm are rarely right, better to measure center of swing arm pivot bolt to center of the axle to true wheel in the swing arm,
2nd with the axle nut lightly tighten get the wheel spinning and firmly apply and hold the brake then tighten axle nut, this will center the brake shoes/back plate to the wheel hub

 

[Rlauchard]

Good info/thoughts Leo/5twins!

Since I put on Hugh's Shorty pipes...I ain't got no center stand. My next post will be about my hernia from lifting the bike up onto stands by myself.

it's up and I'm pulling the tire tonight...I'll check all of these options and report back. Turning the wheel doesn't change the gaps...so it looks like my hub is bent, but I'll also look at a bend on the axle...I got that through ebay, so who knows.

Gettin close, gettin close...

 

[Rlauchard]

So...thanks again...I'm so friggin excited right now.

I spent time last night reinstalling the rear wheel and found that it was the 'chain tighten-ers' that were/are causing the issue. I was trying to 'align' the marks on the chain tighten-er the same on both sides. I think I read that in the manual. But if I do the same on both sides, the wheel gets pulled out of straight and causes the brake plate to go wonky.

I backed off a few turns on the right side of the chain tightener and it released pressure on the plate.

I also followed the advice of applying the brake, then tighten..and it worked like a charm.

This is literally the first time that I've been able to roll/walk my bike without nearly getting a hernia. It's really quite a difference when that rear wheel spins.

Thanks for the help....as an FYI...the bike is 'done'. I'll have to re-torque the head bolts and check/adjust carbs after I ride...but after 2 damn years...I'm getting ready to actually take a motorcycle ride!!!!

 

[weekendrider]

Thanks for the help....as an FYI...the bike is 'done'. I'll have to re-torque the head bolts and check/adjust carbs after I ride...but after 2 damn years...I'm getting ready to actually take a motorcycle ride!!!!

Good on ya for sticking to it.
Enjoy your ride.
The second one will go easier. There will be a second? Oops no, now you gotta build 3.

 

[Rlauchard]

Thanks weekend...my second child was a boy...so definitely 2...the third child (about 2 weeks old) was a girl...not sure what she's going to get.