Front brake pulsing - Honda RC51 Forum : RC51 Motorcycle Forums
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post #1 of 22 (permalink) Old 05-15-2012, 09:27 PM Thread Starter
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Front brake pulsing

I recently developed a "pulsing" when coming to a stop using the front brake. It's like the pads let go for a split second then grab again. Of course the slower I go, the more noticeable it is.

This happened overnight so I have a hard time believing the rotors just warped suddenly, but I don't know what else it could be, unless maybe I sprayed some cleaner on there when cleaning my bike? They're galfer wave rotors and I assume galfer pads. Anyone have any ideas? What's a good way to clean the rotors? Thanks.

05 RC51

08 CBR 1000 (sold)

Last edited by Ponch 7M4; 05-15-2012 at 11:40 PM. Reason: spelling
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post #2 of 22 (permalink) Old 05-15-2012, 10:49 PM
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Could be caused by contamination or glazing at the location.
You could try removing the rotor and lightly sanding it with fine sandpaper or a brake
hone, following by cleaning with brake cleaner to see if that changes the situation.

If you hone or sand the rotor, you'll remove the surface layer applied by the pads during break in.
So treat it as if you installed new pads and brake easy for a couple of hundred miles to re-apply the surface layer.
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post #3 of 22 (permalink) Old 05-15-2012, 11:44 PM Thread Starter
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Could be caused by contamination or glazing at the location.
You could try removing the rotor and lightly sanding it with fine sandpaper or a brake
hone, following by cleaning with brake cleaner to see if that changes the situation.

If you hone or sand the rotor, you'll remove the surface layer applied by the pads during break in.
So treat it as if you installed new pads and brake easy for a couple of hundred miles to re-apply the surface layer.
Thanks SubSailor. I will try that. I must have gotten some Honda cleaner on there, as I haven't always been that careful when cleaning down there. What grit sand paper would you recommend?

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post #4 of 22 (permalink) Old 05-16-2012, 12:10 AM
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I also like to use grey or green scotchbrite pads, when I change between brake pad compounds. I would also take a look see when you take the wheel out, at your caliper pucks. You can take this time to push them outwards (using the brake lever) towards a plywood sheet (width of the disc rotor) placed between the caliper pads, that will stop the pucks from over-extention. Clean exposed caliper pucks with brake cleaner and use a soft toothbrush everywhere. 300 grit or greater sand paper should be okay. I like to use abrasive tape from Norton, instead of sandpaper, for this kind of work. Wraps around the disc easier. Much easier on the hands too.
Brake pulsing is common on this machine for some reason. But a cleaning of the disc and calipers have kept it at bay. I use DP Sport HH pads.

Last edited by rc51 Red Rider; 05-16-2012 at 12:11 AM. Reason: wording
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post #5 of 22 (permalink) Old 05-16-2012, 11:42 AM
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That conditions is pretty normal with Galfer wave rotors at slow speeds.

Having said that they are also very well known in the industry for warpage when used aggressively even during street use which will exhibit the same problems at higher speeds.

Basically they are a really cool product at bike night, but aren't worth a damn for high performance riding. I find it amusing that when you see a lot of the pre-race season photos of the World Supersport race teams on their promo and calender pics etc they all have wave rotors on their bikes, but when the season starts and they actually have to use the products for racing those wave rotors are nowhere to be seen as they all have brembo rotors on them when they come off the track
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post #6 of 22 (permalink) Old 05-16-2012, 02:16 PM
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That conditions is pretty normal with Galfer wave rotors at slow speeds.

Having said that they are also very well known in the industry for warpage when used aggressively even during street use which will exhibit the same problems at higher speeds.

Basically they are a really cool product at bike night, but aren't worth a damn for high performance riding. I find it amusing that when you see a lot of the pre-race season photos of the World Supersport race teams on their promo and calender pics etc they all have wave rotors on their bikes, but when the season starts and they actually have to use the products for racing those wave rotors are nowhere to be seen as they all have brembo rotors on them when they come off the track
Kill Joy, squirrel killin ' bastid......Wave rotors are shyt if you over cook them. I've had better durability out of EBC ultralights.



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post #7 of 22 (permalink) Old 05-16-2012, 08:25 PM
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The rotors that were on my bike originally when I bought it were warped alittle. So I bought some used galfers off of old ebay pretty cheap, and well I think they are warped or just noisey. I think they are getting better as the new pads break-in
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post #8 of 22 (permalink) Old 05-16-2012, 10:25 PM
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When you installed your wave rotors, did you mount one rotor out of phase with the other?
In other words, did you offset one rotor so the slots are not matched?
If not, that could be where your pulsing is coming from, especially as you come closer to a stop.

If your rotors are in phase, pull the wheel and remove one rotor and rotate it so the slots are in between two on the other rotor. Usually by one bolt hole depending on the spacing.

Last edited by SubSailor; 05-16-2012 at 10:28 PM.
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post #9 of 22 (permalink) Old 05-16-2012, 10:48 PM Thread Starter
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Originally Posted by SubSailor View Post
When you installed your wave rotors, did you mount one rotor out of phase with the other?
In other words, did you offset one rotor so the slots are not matched?
If not, that could be where your pulsing is coming from, especially as you come closer to a stop.

If your rotors are in phase, pull the wheel and remove one rotor and rotate it so the slots are in between two on the other rotor. Usually by one bolt hole depending on the spacing.
They were on the bike when I bought it. I remember reading that somewhere else before too, but I don't remember if I ever checked mine. I'll check them.

I just got back from Backfire Moto, a local bike night. As I was leaving I almost tipped the bike over because I slipped in the huge puddle of drool that was surrounding my bike, presumably because of the Galfer wave rotors.

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post #10 of 22 (permalink) Old 05-16-2012, 10:53 PM
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lol...its all about the rotors huh....

I like Subs take on this and makes sense. Is that a standard mounting procedure for the wave style rotors??

I know I over cooked my last set and warped them. (Hell, laying them on the flat concrete floor proved that to me)

Make me wonder if a slightly warped set of any rotors could be rotated to find that "harmonic" balance to minimize if not eliminate the vibration.



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