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New Hayes Prime Disc Brakes – More Photos, News

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Hayes Disc Brakes’ new Prime hydraulic brakeset is reinventing a few ideas around disc brakes, which we covered in this post, but they continue to trickle out new bits.  Here are the official photos, albeit with the Poppet Cam Stroke Adjustment still fuzzed out.

More pretty pixels after the break…

The PRO model gets titanium and aluminum hardware, a titanium master cylinder push rod, and laser-etched graphics (shown), giving it a higher-end look and feel than the black EXPERT.


Click any image to enlarge. The top loading pads are held in place with a small allen bolt pin (gold), and the larger opening will help vent excess heat quickly.  The silver bit between the pads is a “sandwich” spring that pushes the pads out when not engaged, eliminating that dreaded pad rub / brake drag.  Both of these are new developments for Hayes, which has in the past used a patented pad spring retention system that “hooked” the pad to the piston.  This new system should not only ease maintenance but also increase long-term durability.

The PRO level hose is extremely stretch resistant, giving the brakes a more responsive feel at the lever and preventing power loss.  Not shown here, but the production banjo on the PRO model will be anodized aluminum.  Both the PRO and EXPERT models get new seals to further improve durability in foul conditions.

Note the absence of a visible bleed port.  On the Stroker brakes, there’s a small rubber nipple covering a bleed port.  With the Prime, you’ll thread a bleed fitting directly into the bolt that holds the banjo onto the caliper and bleed as normal.  There’s a video tutorial on this here.


The rotors get a new machining pattern to reduce noise.  The aluminum center section reduces weight, but they retain the proven stainless steel braking surface.  Showing the XC-to-Downhill versatility of the Prime, rotors will be available in 140 (rear only), 160, 180, 203, and 224mm diameters.



Still no official word on the Poppet Cam, but word on the street is it’s a tool free pad contact adjustment that you can thumb into submission while riding.  Oh, and it’s a totally redesigned bore for the master cylinder.  And it’ll bring about world peace…at least, that’s what we hear.  And if it’s on the Internet, it’s gotta be true.

Pricing, weights and more info in this post.

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14 years ago

The caliper looks like a clone of Avids Elixir caliper

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