AMP disc brake caliper adapter to IS...FRONT and REAR

Re:

That explains why on a frame I used to have had one of the rear pivot assemblies fitted the wrong way round compared to the other side. Makes sense now and maybe a partial solution to the rotor clearance problem. The triangle is another challenge....
 
here are finished brackets. ordered M5 bolts/nylocks and buying a "donor" bike with disc brakes and 26" disc wheels tonight. Should have this together by early next week.

Took a look at my frame. I think the rotor will clear the triangle, but not sure of the pivot nut yet. Mine stick out like the pics posted...we'll see
 

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Look the part.
I wonder if the rear will need a spacer on the axle. The rear adapter needs to be in line with the drop out. Otherwise I found the caliper sat inboard of the rotor. On my first attempt I needed a spacer the same width as the adapter. This meant the disc (160mm) cleared both the frame and the the pivot nut.
This was my first attempt. You can just see the spacer.

dscf5493-001.jpg
 
the way these brackets were designed, according to the OP, was to be mounted to the outside of the fork tab (as in pic) and rear dropout (no pic of that).

The spacers then bring the caliper back into alignment with the rotor. In the original thread, it was stated that the same adapter would work for fork and frame. We'll see about that.

All a theory at this point, so we'll see how it plays out!
 

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Ok, got front bracket mounted and it works like a charm! Allows me to get a 203mm rotor/caliper on there and fit is perfect.

The rear bracket was not designed correctly (it contacts frame and does not place caliper far enough away from stay to accommodate a 160mm rotor). I am having one redesigned off of measurement I've taken. Stay tuned

The good news is I was able to get a 160mm rotor/disc wheel to fit the frame by swapping the frame pivot bolt to a panhead M5 and adding a spacer to the non-drive side axle (a crank bolt washer!). The fit is snug, but good to go. I'm also having a small bushing machined to take the place of the hex bolt head that was countersunk into the frame pivot.

This should all be available as a "kit" once I get the rear bracket sorted. As it is now, the fronts are ready to rock!
 

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Looks good. Job well done. 203mm on the front is quite a size for those old AMP forks. Like wise 160mm on rear. There has been chat on here in other threads about older frames and larger rotors and the forces exerted.
Cautious would be my approach. Many have accused the AMP forks of being "noddles" (not my experience) so maybe 180mm/160mm? The size of the original AMP discs might be a good guide.
I'm using 180/140mm (from memory).
 
Yes...203 is what I had on hand, so that is what is on there for now. I'm not so worried as they are mechanical calipers. I don't think I'd run hydraulic calipers with such a big rotor

Hard to believe the whole back of the bike is held together with M5-8 bolts!
 
Front is ready to take orders. I assume the bracket will work with other rotor sizes, but only have the 203mm rotor and corresponding caliper post-mount bracket to test.

Rear, maybe another 1-2 week?

Does not make sense for me to have them fabbed up unless several people have interest, so spread the word. The more that want them the cheaper they get.

Here is an interest list. Fill in your user name if you want brackets and indicate FRONT, REAR or FRONT AND REAR. (is there a better way to do this??) .

1. AmpresarchB3: FRONT AND REAR
2. r32: FRONT AND REAR
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