Disk Brake Conversion on Wishbone Frame

[VonWegener]

I find the last shop dope paragraph about brake relining and adjusting very interesting. Loosen the pivot and applying full pressure? I never thought of that.
Thank you Eric. Great contribution as always.

[richbob]

Don’t you read your manual ? Von .

[FredoTwoWheels]

Hey guys, yeah, the axles are supposed to be the same, but I also prefer the way the big blocky early one looks.

Mike, hugely grateful for the offer but I already had a buddy order one of the rods for me. Im going to try to salvage the clevis, but if I run into an issue, I will let you know! Really appreciate the offer and advise, always.

That shop dope is very interesting. I went out and looked at the brake for the first time since unloading it from my truck. I have a bunch of play front to back in the cam shaft. I looked it up in the part in the parts catalog, 4055-31. I expected a washer, maybe being told to shim to fit, but the part specifies a spring washer. What I assume is the issue without opening it, is that the person I bought the brake from used a washer, and since I didnt know any different, may have perpetuated my issue when I swapped components between backing plates. No spring will allow the slop and that probably translates to the chatter. That would make sense why the rod broke, it was probably whipping around while I braked. I will see if I can get my hands on one of the spring washers, may even rebuild some oem brake shoes I have kicking around to replace the aftermarket ones in there. If after that it still rattles, then I will just have to throw out the whole bike. Ha!

[Dutch Dennoz]

Originally Posted by FredoTwoWheels

Hey guys, yeah, the axles are supposed to be the same, but I also prefer the way the big blocky early one looks.

Mike, hugely grateful for the offer but I already had a buddy order one of the rods for me. Im going to try to salvage the clevis, but if I run into an issue, I will let you know! Really appreciate the offer and advise, always.

That shop dope is very interesting. I went out and looked at the brake for the first time since unloading it from my truck. I have a bunch of play front to back in the cam shaft. I looked it up in the part in the parts catalog, 4055-31. I expected a washer, maybe being told to shim to fit, but the part specifies a spring washer. What I assume is the issue without opening it, is that the person I bought the brake from used a washer, and since I didnt know any different, may have perpetuated my issue when I swapped components between backing plates. No spring will allow the slop and that probably translates to the chatter. That would make sense why the rod broke, it was probably whipping around while I braked. I will see if I can get my hands on one of the spring washers, may even rebuild some oem brake shoes I have kicking around to replace the aftermarket ones in there. If after that it still rattles, then I will just have to throw out the whole bike. Ha!

Can you throw it across an ocean?

[FredoTwoWheels]

Soooo, today the backing plate anchor sheered off on the freeway. This brake wants blood.

[rhysmort]

Originally Posted by FredoTwoWheels

Soooo, today the backing plate anchor sheered off on the freeway. This brake wants blood.

That's not good dude... something is definitely awry with the alignment/spacing. Need to get that looked at before it does get blood!

[joe49]

Who made the anchor stud?

[rhysmort]

Originally Posted by joe49

Who made the anchor stud?

This is like the 3rd? he's sheared, Joe. I've never ever seen 3 go in a short period of time unless there's something wrong (alingment) A friend had one go, but it was 35 years old. It could be a Vtwin taiwan special, but I'd like to think he'd pay a little more for quality being as it's his only brake!

[richbob]

3 studs sheared ? Interesting

[joe49]

One brake, three sheared, his luck is going to run out.

[FredoTwoWheels]

Once I sheared a cotter pin, next time the rod snapped, this time the anchor sheared from the backing plate and engaged the brake on the freeway. It was a Paughco, had it for two or three years.

[rhysmort]

Originally Posted by FredoTwoWheels

Once I sheared a cotter pin, next time the rod snapped, this time the anchor sheared from the backing plate and engaged the brake on the freeway. It was a Paughco, had it for two or three years.

My apologies I knew there had been a few ocurrences.

I think something is misaligned man, 3 things shearing on a there says to me there's forces working with misalignment of some sort. It could be the drum, but I doubt it, Paughco tend to be good quality. Are you certain on spacing and your frame being straight?

[FredoTwoWheels]

Frame was originally straightened by Dr Johns in Anaheim.

So I looked at the bike for the first time since the breakdown, I usually need a cooling off period after getting it home. The damage is much worse than I thought.

I am not sure which came first, the brake issue or the weld breaking, but now they are both kaput. What I think happened is the brake anchor went and the force of the backing plate rotating and hitting the bottom of the axle, it broke the weld and bent the upper tube.

Scenario two is that all the vibration from the brake weakened the weld and the crack developed, allowed the axle plate to flex. This let the backing plate slip out enough to run away from the stay and the damage to the anchor I see is after the fact. This is equally as possible because beginning the day before, I felt the brake grabbing a little like it was wearing unevenly. This could have been from the weld going or the anchor beginning to sheer.

So now I need to have some frame work done. I could go back to Johns, but I'm pretty sure he will want me to just bring the bare frame. I would prefer not to strip the bike down completely, I dont have the space for so much work right now. Anyone have any great frame guys in SoCal I can talk to?

[richbob]

Fuck
That’s unlucky it did so much damage

[joe49]

Not to bad. While that could be fixed with out stripping the bike, most frame repairs are done on bare frames. Easier to check for location and straightness.