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Discussion Starter #1
I'm looking to pick up a Lady Bird underslungrear brake caliper bracket with the 64mm spacing. Anyone have a line on one?
 

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Discussion Starter #3
found one. a bit pricey but fairly rare. The plan is to capture it to the swing arm to make wheel changes much easier.
 

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Discussion Starter #5
I was able to get my hands on the Brembo P2.34 caliper. Its a bit smaller and lighter but the biggest reason was it was donated to the cause. Can't beat that with a stick.
 

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that's all fine and dandy, but what holds the bracket in place?

i'm going to be making my bracket captive right away here. just trying to find the best way to do it. a lot of people will just fasten the axle block to the bracket, but this doesn't allow you to pull the block out of the way and slide the axle all the way forward to pull the chain off. i'm looking at options for fastening the bracket to the swingarm. i'm thinking of just milling a slot in the bracket and then putting a bolt through the top of the swingarm bracket to engage the slot.

we'll see though.
 

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Discussion Starter #11
So my plan is to machine a steel sleeve 27mm OD and 25mm ID. I will have to open up the 25 mm opening on the caliper bracket, Giles chain adjuster and the swing arm to 27mm. Slide the sleeve through the giles chain adjuster, swing arm then press it into the brake caliper bracket. The load will be supported by the steel sleeve. The chain adjusters will then be free to slide forwards and aft as they do now. As far as sliding the wheel forward to allow enough room to get the chain over the sprocket, the shelf on the bracket will handled that and just the wheel will slide fore and aft, the caliper bracket will stay in place. I have found that i only really need about and inch or so of forward movement to get the chain on then pull the wheel to the rear and slide the axle in. Milling the slot in the swing arm to allow the forward and aft chain adjustment is going to be the trickiest part though. Its should not be that much of and issue I will just need to be careful to make sure I take off just the right amount evenly top and bottom.
 

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there's no way in hell i'd be machining the swingarm. not only because it has to come off the bike, but also because it'd be a nightmare to fix in a mill.



i don't really like the sleeve thing at all, because if it's only pressed into the caliper bracket then it can still fall out, and if you pressed it into any other part then the whole assembly would bind.


your best bet is to fix it at the locating arm.


i'll post up my solution when i get it done.
 

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Discussion Starter #13
I presently have the caliper bracket captured to the locating arm. It works ok but there is a bit more play in it than I would prefer. Milling the swing arm is definitely not something I'm looking forward to as it will be a pain in the ass but if done correctly the wheel spacer will register on the sleeve preventing it from getting compressed too much and cause binding. I'm planning on making the fit tight enough to not fall off but not so tight as it will never be able to be taken off. But I'm interested is seeing other methods of capturing it too. Another option would be to change the axle size from 25 mm to maybe 23 mm, sleeve it and accomplish the same thing. No milling of the swing arm and I would only need to re machine the wheel spacers and axle nut.
 

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A new axle would certainly work, but is also a lot of work for something so trivial.


How did you capture the locating arm
 

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Discussion Starter #15
I slotted the block on the bracket then drilled and tapped a hole in the inside of the groove then put a allen head bolt in it allowing it to slide forward and aft. There was enough tension on it to allow it to slide, but also enough to keep it in place when the wheel was sitting there. It worked out ok but there is a better more secure way to do it which is where I'm at now. I really like how the HRC stuff goes together but my machine skills might need some improvement.
 

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