Hello,
Some times ago I bought a strange Hayes calipers. I know that is old pre-G1 style but what years is it??? How it work?
If I understood right - it's "closed" (there are 2 bleeding valves on caliper!!!) hydro system, BUT with using mechanic brake levers? Am I right?
Somebody used this system? May be have a catalog or review?
Thanks!

interesting having two bleed nipples but you would use the one that is uppermost when fitted.

I would guess it has two either because there may have been more half castings to make up different calipers (it is two pieces) or it is there so when mounted on front fork, one nipple is used for bleeding as it is upper most but other bleed niple is uppermost when on the rear. (mounting on rear could be outside the chain stay or within it, the latter being an early and now abandanoned design).

strange mounts though - are they post mount compatible or require an adapter?

My 2p worth........ it's a cable actuated hydraulical caliper. The cable goes straight in the top, as seen from your first picture, fixed with a grub screw. I'd think of the two bleed nipples as an "in" and an "out" , bleed from the lower to upper with a syringe. (total guess work here). I remember seeing these on GTs in late nineties (97/98?) - they weren't a great brake, but I guess it was cheaper to produce that a full hydraulic system at the time.

Reluctant is right, it is a cable actuated hydraulic caliper. They only made them for a year or two and were not popular.

Thanks for help! I was right
And now I don't know where to use it .... Need to buy mech brake levers

well there you go, you learn someting every day - I assumed the "cable in" was the port for cnnectng brake hose but can now see the plunger.

interesting design, should work with either a v-brake lever or cantilever brake lever - my guess again.

PS is it snowing yet in Moscow?

They would need a v-brake lever, were made in 1999.


It was supposed to be an easier and cheaper way to get people using discs from what I recall. I have one of the Dia-comp discs from the mid-90's that works the same way, makes no sense at all really. But I still want to try using it someday just to see how useless they are.

Haha:) No, today was great - sunny and +16-18C temp.....Even in "cold" Syberia still comfortable - +15C
Probably snow come in Moscow in the end of November or even early December.... It's true!

Baulz thanks for answer.