can you put most modern brake systems onto frames with a hayes mount on the rear of the frame rather than the new syle of mount that most manufacturers use now? or do you need hayes specific calipers etc etc.

some hayes mounts sit on the chainstay so thr caliper sits inside the rear triangle. I doubt you'll fit an adapter and a caliper in there. If it is on the seat stay then you can get an adapter. You might be restricted to certain rotor sizes.

yeah chain stay type inside the triangle…thats what im on about…?

As far as I am aware the only brake that you can mount on a hayes 22mm mount that is even vaguely modern is the hope C2. They occasionally crop up on Ebay. It needed a special caliper half and adaptor mount, both of which I have. If you need them give me a bell (email in profile).

I don't think any other brake will fit.

This any good to you?
All Terrain linky