Post mount disc 140 to 160mm

secretsam

Hiya. I have an older bike with 140mm post-mount front brakes; I want to put a 160mm rotor on there, do I need an adaptor?

Wheelspinner

Yes. The fork mount tabs are sized to position the caliper correctly for the disc diameter.

Something like this will do the trick:

https://www.merlincycles.com/en-au/tektro-disc-brake-adaptor-199047.html

The adaptors come with longer bolts which you'll need as well. It says here it comes with the mounting hardware....

There are just spacer kits instead of a one piece like this but they're dearer and look less secure (to me anyway).

There can be issues sometimes with these adaptors fouling the caliper, so it is a bit of a lottery that it fits no issue - I used to have problems with Magura brakes needing quite specific ones as the Shimano or Avid ones didn't work. But that Tektro above looks pretty generic.

secretsam

Cool, thanks