Which brake model to Use for GIANT ATX One DH?

[DaHaoZ]

Hello everyone. I just bought a Giant ATX One DH frame. I think is an earlier model, because its brake mount is "inside" the rear angle. Please find below the picture.

I had an in depth search on the web. This earlier model should be equipped with a Hope C2 brake. But I know that C2 has many types of "Numbers", from 1 to 11, which made me very difficult to choose.

Is there anyone who could tell me which "Number" of the C2 brake caliper should I choose for my GIANT ATX One DH?

Thank you very much in advance.

Howard

 

[just jacques]

If the mounting holes are 51mm apart you'll need either a no3 or no5 depending on disc diameter.

 

[DaHaoZ]

If the mounting holes are 51mm apart you'll need either a no3 or no5 depending on disc diameter.

Thank you very much, Jacques. The measurement between the two mounting holes are about 43mm on my bike, not the international standard, 51mm. Do you know which type of caliper shall I choose? No.3?

 

[DaHaoZ]

I found a picture from the web, it looks like the caliper No.1. Please correct me if I am wrong.

 

[sam_white]

Could it be a Formula mount, rather than IS? Check the hole diameter, M5 would be Formula, M6 would indicate IS.