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I have a Specialized Demo 9 and I ride at Big Bear. The brakes are HFX 9 with the 8" rotors. So far, other than the levers constantly coming out of adjustment (which I shall soon remedy with loctite), I am really pleased with the brakes--they are powerful, modulate well, and stay cool even on full-tilt DH courses.

On my 3rd trip up, at the end of the day, I noticed 2 things. First, I looked in the pad wear window, and it looked as thought the pads were completely worn out (I have not removed them to check the pads yet, so it's possible that they may still be good). I then felt the rotors, and found that they were grooved. It is a wide, flat groove that essentially occupies the entire area where the holes are punched in the rotor. Both rotors have it. I did not notice any change in braking performance.

Is this normal for Hayes pads to wear so quickly? Are the grooves in the rotor typical? I think the pads are the semi-metalic, not the full sintered metal. Also, if the pads are shot, can I put new pads on the grooved rotors or do I need new rotors?
 

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New pads.

BigDigger said:
I have a Specialized Demo 9 and I ride at Big Bear. The brakes are HFX 9 with the 8" rotors. So far, other than the levers constantly coming out of adjustment (which I shall soon remedy with loctite), I am really pleased with the brakes--they are powerful, modulate well, and stay cool even on full-tilt DH courses.

On my 3rd trip up, at the end of the day, I noticed 2 things. First, I looked in the pad wear window, and it looked as thought the pads were completely worn out (I have not removed them to check the pads yet, so it's possible that they may still be good). I then felt the rotors, and found that they were grooved. It is a wide, flat groove that essentially occupies the entire area where the holes are punched in the rotor. Both rotors have it. I did not notice any change in braking performance.

Is this normal for Hayes pads to wear so quickly? Are the grooves in the rotor typical? I think the pads are the semi-metalic, not the full sintered metal. Also, if the pads are shot, can I put new pads on the grooved rotors or do I need new rotors?
This is fairly normal. More than likely, some type of grit or whatnot found it's way between the pad and rotor. You might try cross hatching the rotor with sandpaper before the new pads go in, but you do not need to. The new pads will find the grooves quick enough. GO ride!
 

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Discussion Starter · #3 ·
damion said:
This is fairly normal. More than likely, some type of grit or whatnot found it's way between the pad and rotor. You might try cross hatching the rotor with sandpaper before the new pads go in, but you do not need to. The new pads will find the grooves quick enough. GO ride!
Thanks Damion,

I figured that was the issue, but I wanted to be sure. My other bike has Magura Martas on it, and the rotors are in significantly better shape with quite a bit more mileage, so I thought I'd check.

Also, is pad wear normally that quick with the Hayes semi-metallics? Should I try the sintered metal pads?
 

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I just looked at my new front rotor that I put 10 miles on and it looks just like you desribed, so I'm concluding its just a new rotor thats not broken in smooth with the pads shape yet. Never used the semi metallic, but you should get the sintered metallic, they wear slow considering.
When you get your new sintered pads take the old ones out with needle nose pliers and push back the pistons so they are at least just below the housings(might take 5 mins to get em there). New pads are thicker yet so you gotta push the pistons back in there bores. Put the new pads in and mount caliper just loose enough it moves side to side, then you pull the lever and the pads close on the roor to set the pistons the caliper should move centered over the rotor. Then snug up the two bolts, and recheck the spacing after first ride. Mine was centered but now after riding looks like it needs recentered. You want the rotor equal distance from the pads both sides or the disc flexes first and you don't get equal pad pressures.
The EBC reds on my rear didn't seem to good in the rain today, they are ok in dry, still not sure if they out stop the sintered metallic Hayes pads in all conditions.
Check Hayes website for more brake tips.
 
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