Post mount to flat mount caliper conversion

[Duckfoot1606]

Afternoon all

I have a mark 1 Spa Elan with cable discs, 160mm rotors and 105 11 speed shifters. The frame and fork have post mounts.

I have seen a tempting offer for 105 hydraulic shifters with flat mount calipers, so presume i will need adaptors of some sort to fit the calipers to the frame and fork, which by implication and visual assessment will move the caliper away from the frame and thus suggests I will need a larger diameter disc - how do i work out the rotor diameter i need?.

Thanks in advance

A

[Stuart Anderson]

https://www.wolftoothcomponents.com/blogs/news/add-flat-mount-brakes-to-post-mount-frames-and-forks-with-our-new-post-to-flat-mount-brake-adapter

https://www.sjscycles.co.uk/brakes/cinq-disc-brake-adapter-post-mount-frame-to-flat-mount-plus20-mm-caliper/

[Hot Flatus]

...or

https://www.assolutions.ca/shop/adapters/flat-mount-brake-caliper-to-160-post-mount-frame-fork-with-160-rotor/

But AFAIK these are your only choices

[Hot Flatus]

Good news!

Just found these on Ebay. Much cheaper

https://www.ebay.co.uk/itm/235480362772?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338749377&toolid=20006&_ul=GB&customid=GB_888_235480362772.141484260406~1866858443448-g_Cj0KCQjwiMmwBhDmARIsABeQ7xQh4DXvNA0Ojv9sqUsy-5V7Xn0b0MUzD08I0Dp0ydUYJCWCWLOm_mkaAkcuEALw_wcB

If frame was designed for 160 then you'll need 180 rotors with these.

Why not just get PM calipers??

[rr]

https://www.sjscycles.co.uk/search/?term=Zrace
Considerably cheaper direct on AliExpress or the bay of thieves

[Hot Flatus]

here we are...

https://www.ebay.co.uk/itm/386267032384?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=fua1tykytli&sssrc=4429486&ssuid=fafun6UAQEW&var=653809881724&widget_ver=artemis&media=COPY

But you'll still need 180 rotors

[grams]

You can use absolutely any Shimano hydraulic post mount calliper with 105 levers (e.g. BR-MT200), and they cost about the same as those adapters and new rotors.