# Disc brakes adaption?



## mpdoan2 (Aug 21, 2019)

Has anyone put disc brake adapters on any of their pre-war bikes? I'm going to try something fun with my '41 Elgin, but I don't want to damage it (so I have the option to go back to original design). Thinking of either this aluminum one that just slides into the rear drop out (but not sure if rear dropout is beefy enough) or this alloy one that would sit on the axle and clamp to the seat stay (but not sure what the stress to this area of the seat stay when braking might do).
Thanks for any input!
Mike


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## bricycle (Aug 21, 2019)

I think you'd be happier with the black one.


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## rbertjr (Aug 21, 2019)

I have installed the aluminum one on a 1939 Schwinn DX frame.  I had to widen the distance between the chain stays to accommodate the adapter as well as an 8-speed internal gear hub.  In addition, I had to make a shim made from aircraft aluminum to line up the disc.  Once all bolted together, the brake works really well!


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## Mr. Monkeyarms (Aug 21, 2019)

Cool! I've seen people do this to a vintage ride but can't remember who or where. I'm sure the old American steel stays will be strong enough to handle the torque from a disc brake.


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## saladshooter (Aug 21, 2019)

I think we need to see the whole bike! 



rbertjr said:


> I have installed the aluminum one on a 1939 Schwinn DX frame.  I had to widen the distance between the chain stays to accommodate the adapter as well as an 8-speed internal gear hub.  In addition, I had to make a shim made from aircraft aluminum to line up the disc.  Once all bolted together, the brake works really well!
> 
> View attachment 1050879


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## mpdoan2 (Aug 22, 2019)

rbertjr said:


> I have installed the aluminum one on a 1939 Schwinn DX frame.  I had to widen the distance between the chain stays to accommodate the adapter as well as an 8-speed internal gear hub.  In addition, I had to make a shim made from aircraft aluminum to line up the disc.  Once all bolted together, the brake works really well.
> 
> That looks great! Thanks.


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## sarmisluters (Aug 22, 2019)

That’s a nice option for all of our old bikes


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## CURTIS L LINDGREN (Aug 22, 2019)

rbertjr said:


> I have installed the aluminum one on a 1939 Schwinn DX frame.  I had to widen the distance between the chain stays to accommodate the adapter as well as an 8-speed internal gear hub.  In addition, I had to make a shim made from aircraft aluminum to line up the disc.  Once all bolted together, the brake works really well!
> 
> View attachment 1050879



I Second that !     Let's see the WHOLE BIKE !     Clean Set Up there !


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## bricycle (Aug 22, 2019)

are there kits out there, as I have no idea how to mix and match?


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## rbertjr (Aug 22, 2019)

BicycleDesigner.com does have a kit which includes the aluminum bracket and the disk brake/rotor.  Below is the whole bike.  I took it to a modern Klunker extreme with front/rear discs, carbon fiber fork, Renthal stem/handlebars/kevlar grips, Schmidt headlight/dynamo hub, custom stem lock, motorcycle fork clamps for front brake cable and headlight wire, limited edition Sugino Maxy Cross cranks/sprocket, Bombshell rims, JAGWIRE cables, Shimano IGH with trigger shifters, and a Brooks B72 seat.  The frame was silver brazed/smoothed and then triple chrome plated.  I built the bike for my 11-year old son and he loves riding it!  Below are some photos.


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## Hammerhead (Aug 23, 2019)

Could you please post a closer pic of the rear disc side from an angle? Thank you @rbertjr  Sweet bike!
Hammerhead


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## Duchess (Aug 25, 2019)

I used the black-style one on the rear of a '61 Columbia Firebolt—not prewar, but I don't think it matters much. Seemed like it was going to be flimsy until it was all bolted down tight and now it works like it's part of the frame. Getting the right bracket for the caliper and shimming for alignment was a little work, but not too bad. In my case, I was also converting to a 6 speed freewheel and derailleur I had around and I didn't want to dish the wheel, so that's where a little bit of the trickiness came into play. The most difficult part was actually the disc. I used a flip flop hub and a thread-on disc adaptor for the non-drive side. I ended up doubling the adaptors to get enough standoff distance from the hub, which required drilling the threads out of the outer one and grinding down the outer flange so the two could bolt flush and true.


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## rbertjr (Aug 31, 2019)

Hi Hammerhead:
Sorry for not posting sooner.  Please see photos below.  If you need more, just let me know.


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## Hammerhead (Sep 17, 2019)

Thank you @rbertjr  awesome set up.
Hammerhead


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## Duchess (Sep 17, 2019)

The other style:


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## NoControl (Sep 21, 2019)

rbertjr said:


> 1939 Schwinn DX frame.




I'm completely blown away by this frame. I'd love to hear your story on how you did it sometime.


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## El Hefe Grande (Oct 1, 2019)

What an Awesome Build !!!

and a Lucky Son !


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