London Road Caliper - Head scratch

ed1973

Hi all
I’ve got a Planet X London Road project I’m on at the mo. Got sent a nice groupset with some trp mechanical brakes. Front brake caliper was no problem, rear caliper would not go on. LBS said I need an Avid BB5 or BB7 as it’s a post mount on the rear. I’m fine getting a BB5 from wiggle (other shops are available but wiggle seem the cheapest). Just looking at how to attach it and just can’t seem to picture it.
Are the bolts provided long enough?
PS Planet X were also helpful and said BB5 would be fine

ed1973

Update
I really like the TRP Spyre-c caliper so am thinking of getting an adapter. The London Road I have has 73mm wide post mounts so the flat mount (I think) TRP caliper won’t fit on. I have attached a picture of an adapter on an auction site. Would it work? I reckon I would also need to a 180mm Centre lock rotor as I reckon the post mounts are set for a 160mm rotor
Thoughts?

whyamihere

That adapter is for a flat mount frame and a post mount caliper, the opposite to what you want. There are adapters (like this one https://www.merlincycles.com/wolf-tooth-post-to-flat-mount-brake-adaptor-271466.html), but generally they require a 20mm larger rotor, and as the London Road is set up for a 160mm post mount brake, you'd be running a 180mm rotor which isn't a good idea. They also don't fit every frame so you'd need to measure it.

I would just go for a post mount caliper. Spyre SLCs are available in post mount: https://www.merlincycles.com/trp-spyre-slc-post-mount-disc-brake-caliper-106632.html or you could just get something cheaper like a BB5. Mounting bolts for post mount are simpler than for flat mount as they only pass through the caliper into threaded holes in the frame, rather than passing through the frame which could require different length bolts.

ed1973

whyamihere said:

That adapter is for a flat mount frame and a post mount caliper, the opposite to what you want. There are adapters (like this one https://www.merlincycles.com/wolf-tooth-post-to-flat-mount-brake-adaptor-271466.html), but generally they require a 20mm larger rotor, and as the London Road is set up for a 160mm post mount brake, you'd be running a 180mm rotor which isn't a good idea. They also don't fit every frame so you'd need to measure it.

I would just go for a post mount caliper. Spyre SLCs are available in post mount: https://www.merlincycles.com/trp-spyre-slc-post-mount-disc-brake-caliper-106632.html or you could just get something cheaper like a BB5. Mounting bolts for post mount are simpler than for flat mount as they only pass through the caliper into threaded holes in the frame, rather than passing through the frame which could require different length bolts.

Thanks so much for the feedback, helps a lot.

ed1973

whyamihere said:

That adapter is for a flat mount frame and a post mount caliper, the opposite to what you want. There are adapters (like this one https://www.merlincycles.com/wolf-tooth-post-to-flat-mount-brake-adaptor-271466.html), but generally they require a 20mm larger rotor, and as the London Road is set up for a 160mm post mount brake, you'd be running a 180mm rotor which isn't a good idea. They also don't fit every frame so you'd need to measure it.

I would just go for a post mount caliper. Spyre SLCs are available in post mount: https://www.merlincycles.com/trp-spyre-slc-post-mount-disc-brake-caliper-106632.html or you could just get something cheaper like a BB5. Mounting bolts for post mount are simpler than for flat mount as they only pass through the caliper into threaded holes in the frame, rather than passing through the frame which could require different length bolts.

whyamihere said:

That adapter is for a flat mount frame and a post mount caliper, the opposite to what you want. There are adapters (like this one https://www.merlincycles.com/wolf-tooth-post-to-flat-mount-brake-adaptor-271466.html), but generally they require a 20mm larger rotor, and as the London Road is set up for a 160mm post mount brake, you'd be running a 180mm rotor which isn't a good idea. They also don't fit every frame so you'd need to measure it.

I would just go for a post mount caliper. Spyre SLCs are available in post mount: https://www.merlincycles.com/trp-spyre-slc-post-mount-disc-brake-caliper-106632.html or you could just get something cheaper like a BB5. Mounting bolts for post mount are simpler than for flat mount as they only pass through the caliper into threaded holes in the frame, rather than passing through the frame which could require different length bolts.

Would this work?

https://www.condorcycles.com/products/trp-spyre-c-mechanical-disc-brake-caliper?siteid=1498975&source=webgains&variant=44384230375745&wgexpiry=1710526111&wgu=281345_1498975_16789901114174_667e86f96a

whyamihere

Yes, it should do as long as you select one of the post mount variants. I'm not sure why they're distinguishing between front and rear as the calipers are the same for front and rear, but that won't cause any problems.

ed1973

whyamihere said:

Yes, it should do as long as you select one of the post mount variants. I'm not sure why they're distinguishing between front and rear as the calipers are the same for front and rear, but that won't cause any problems.

Awesome thanks for this. It will go straight on with no adapter so I’m hoping that the mounts are faced well!