Topic: Brake backing plate rubbing (UPDATED - pics and info added)

[Scott S]

 It appears that the brake backing plate is rubbing on the wheel. I'm using the '71-76 style backing plate and Henry Abe wheels.
 I can hear and feel a little grinding noise when pushing the bike around, and I see some shavings on the wheel.

 Is there anything I can do to remedy this? I'm nearly positive that I have all the spacers and such installed.

[Flyin900]

I don't know your mods/wheels, so someone else may have an opinion there.

How are the wheel bearings? I had a later model bike disc rotor rubbing a rear caliper because a wheel bearing had too much play and was not rotating uniformly anymore.

[Scott S]

 Wheel bearings are new All Balls bearings.

[strynboen]

have you tryed a 78 f/ k plates.. late .f and k plate"s is a bit different..i had some problems mixing old and newer hubs and brake plates

[Scott S]

 I thought the later K plates were larger? Isn't the rear hub larger on the later bikes?

 Now that I think about it, I believe that the bike these wheels came off of was a '77 or '78, but its been so long since I bought them that I can't remember for sure. And the swing arm is definitely an F model.

[jonda500]

My HenryAbe 16" mag came with the later model 550(77/78) brakes. I have never tried putting a 500 backing plate in it though, John

[Scott S]

 Hmm....and wouldn't you know it, I gave my set of wheels with the later style backing plate to the guy that bought my 550F!
 Guess I'll have to search for a later style backing plate.

[Scott S]

 Wheel bearings are new All Balls bearings
 


 This bike is my "Sweep The Floor 2" bike, so it's a K frame with an F swing arm. I found out a while back that I needed the F spacer. The longer F spacer is what's in there now.



 Thanks to forum members Nicks2319, here are some pics showing the height difference between the early brake backing plate (what I have now) and the later '77-78 style (the kind with the ribs).



 He also informed me that there are two different spacers for the sprocket side. I'm not 100% sure which one I have, but I think it's the shorter of the two. Also, I'm not sure which one is supposed to be used with which backing plate. Anyone know?



 Here's where the plate is rubbing. It's hard to get pics, but you can maybe see the plate is more flush than it needs be. It's especially rubbing at the front.






 One other sanity check I'd like is on the sprocket side spacer or collar. I used the parts diagram when assembling the wheel, and I did them just like the Lester's I rebuilt (and no issues with them). Is the collar in the correct place? Shouldn't you be able to see it like this? Unfortunately, I just sold my other 550's and now have nothing to compare it to.

[Scott S]

 It looks  like the collar on the sprocket side is the same part number from '71-78; part # 42311-323-40. That pretty much leaves the backing plate as the culprit, no?

[jonda500]

the sprocket side spacer only comes in two sizes - the longer one is an 'F' and the shorter one is a 'K' one. they are normally trapped under a sprocket cover(chain guard) which has a seal in it which the spacer goes through - the 'K' type barely shows as it only pokes out slightly. The brake side spacer is different (shorter) for the later model backing plate and also different (longer) for the 'F' swingarm - so there are 4 different ones, but it is very obvious when the wrong one is used as it wont be even close to the right length! So it looks like the backing plate must be the culprit, John

[Scott S]

 I most likely have the shorter K collar. And I have an F swing arm. Is that going to be a problem? I definitely have other spacers for the RH side.

 I googled and saw pics of the H.A. wheels using both backing plates.

[mystic_1]

Do you have room to fit a shim in between the wheel bearing and the brake backing plate?

mystic_1

[Scott S]

 That's kind of what I was thinking about doing. It probably won't take much. I think k I have some VW alternator shims somewhere. Very think and stackable to get the right thickness, as long as they'll slip over the axle.

[Terry in Australia]

Do you have room to fit a shim in between the wheel bearing and the brake backing plate?

mystic_1

+1 mate, you should be able to pack some shims between the brake plate and the wheel bearing on the brake side until you've got clearance. I didn't have the problem on my 750 though, my wheels went straight on with no issues. Sort it out though, because those wheels look sweet! Cheers, Terry.

[Scott S]

 I found ONE spare VW alternator shim in my nuts & bolts bucket. It fits over the axle perfectly. Luckily, I can get a 10 pack for $6.25 shipped. I like this idea because they're thin and I can stack them to get the correct height.
 I'll report back later.

[Scott S]

 Fixed. Three shims from the VW alternator pack between the backing plate and the bearing and no more issues.

[Scott S]

 Well, the darn thing is rubbing again.
 I found some pics that I nabbed from the eBay ad WAY back when I first bought the wheels and it clearly shows them with the same style backing plate I'm using. And I rebuilt these wheels with new bearings and re-used all the spacers and such that were in them.

 Any idea why a backing plate would rub ad what to do about it? It also seems like the plate is slightly cocked. It's sunken in more at the front and rubbing there.

[strynboen]

try to loosen the shaft vho hold the rear hveel..just so you can tyrn it.....and thek id the brake plate moves bu turning the shaft..if it are bend..it vill give a moving aut/ inn moving of the vhole plate..moving from the front side vearing..to move the vearing to the back side...by a half turn of the shaft,,..( if itr are bend)

[Scott S]

 Gotcha. Think I should loosen the brake stay rod a little bit too, or leave it snug?

[strynboen]

it have that littel rubber thing..so are never real solid..so no need for loosen that up

[Terry in Australia]

The only way that the plate could be rubbing after you shimmed it again is if the internal tube/collar thingie that sits between the bearings in the hub is missing, or is the bearings aren't fully seated. You've replaced the bearings Scott, so go back and make sure that the internal spacer is there, and that the bearings are fully seated in the hub. Cheers, Terry.

[Scott S]

 I take it you mean either part #11 or #12?

[Terry in Australia]

Yeah mate, that's what I'm talking about. They're there to stop the bearing being pushed further into the hub when you tighten the axle nut, so if they're the correct items, and properly installed, the problem you're having shouldn't be happening. Cheers, Terry.

[strynboen]

i had to chim a ekstra on that pos 12..as the bearings vas not running total free.that vas the different-   problem as you have.
.easy fix is to machine a bit od the spacer to get the ekstra free room betveen the bearings to go..
..there must be abaut 0,5 mm free move for the bearings to take heat movement...but not more..think you got a lot more...bad thing is the bearing you vall remove first vill be dead..but that is a low cost..to get it right..but renember the pos 12 must be ca 0,5 mm longer then the machined autbored innerspace for the bearings..

[Scott S]

 Luckily, I have a set of brand new rear wheel bearings on hand for the current project. Even have the rear wheel disassemble at the moment and all parts and spacers on hand. I can rob them to repair this if needed and replace them on the current project later.
 Probably pull the wheel this weekend and see what I find. The bike is for sale and I can't sell it like this. I need to repair it properly.