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Pulsing front brake


ccriderXX

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I recently had my front wheel off as I had gone back to the stock springs in my forks. I lost weight and my gpsuspension modded forks had too stiff of springs. On my test ride in noticed a strong pulsing / shudder in the front. I had not noticed this before, so I assume I must have somehow bent, or dinged my left front brake rotor. I don't know how this happened as I was very careful with the rotors.

I had a ZX11 that had similar symptoms that I had to replace rotors on, so I was pretty sure I had a bad rotor. I had a Harbor Freight dial indicator left over from that issue a few years back. I fashioned up a ghetto bracket to mount the dial indicator. A picture is attached.

The runout tolerance in the manual is .012in. The left rotor measures at .002in, but the right had a big .020in wave. And both rotors are .193in thick, the limit is .16in.

So my '99XX right front rotor is shot. My first thought is to see if anyone has a spare rotor they would like to sell. I assume either side will work. My next thought is some Galfer wave rotors would be nice too. :icon_confused: Any suggestions?

post-1220-1207541625.jpg

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IIRC the rotors are left/right specific.

I went with EBC pro lights because they were a lot less $$ than the stock replacements from Honda.

Good luck

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straighten it, you have the dial indicator!!!!
I assume you are serious since I don't see a smiley. And I don't have anything to lose. I have heard of someone using a crescent wrench to tweek a rotor, and I was thinking of using a rubber mallet. Can this really be done? And my brother in law is a machinist, I wonder if machining it flat would work.
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straighten it, you have the dial indicator!!!!
I assume you are serious since I don't see a smiley. And I don't have anything to lose. I have heard of someone using a crescent wrench to tweek a rotor, and I was thinking of using a rubber mallet. Can this really be done? And my brother in law is a machinist, I wonder if machining it flat would work.

if you have a good metal lathe, you could turn it without much trouble

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if you have a good metal lathe, you could turn it without much trouble

He does have some good lathes, I will have to ask him, but I think he would have to somehow hold the rotor instead of the carrier. Since the rotor floats on the carrier, it seems like it would move while machining. But maybe while machining it cold it wouldn't move much. The floating on the carrier is probably more for accommodating expansion and contraction in use.

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I wouldn't turn the rotors, bend 'em back into shape. Usually the rotor isn't warped, rather the carrier is bent. It's not hard to bend the rotor carrier, happens way too often during tire changes. Which may explain why only one of yours is bent.

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I wouldn't turn the rotors, bend 'em back into shape. Usually the rotor isn't warped, rather the carrier is bent. It's not hard to bend the rotor carrier, happens way too often during tire changes. Which may explain why only one of yours is bent.

So I should use my rubber mallet near the carrier to tweak it back. I will try that. Oh and I did change my own tire, but that was a while ago and I didn't notice the pulsing in the rotor until recently. But I am sure I could have bumped it somehow. :icon_redface:

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Just a thought, but you might have better luck prying it back into shape using a lever of some sort, maybe a large crescent wrench? Slowly and uniformly heating the carrier should also help. But ask Joe or Stan, I'm sure they have more experience than I do.

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well, I was going to let Joe chime in cause I sent nim the center of the front wheel that I got on the zxxx that was broke and bent.

No metal needed to straighten, Please.

Rubber mallet, as a last resort.

Most can be straightened by hand. I use the move it twice the amount bent. Find the middle, or maximum bend and move the correct way. Not as hard as you think.

Let me know, and go in small steps. start with a little and work up to the amount I said. If it is bent 20, move 10 and see if it comes back to 15. Make sence?

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I wouldn't turn the rotors, bend 'em back into shape. Usually the rotor isn't warped, rather the carrier is bent. It's not hard to bend the rotor carrier, happens way too often during tire changes. Which may explain why only one of yours is bent.

So I should use my rubber mallet near the carrier to tweak it back. I will try that. Oh and I did change my own tire, but that was a while ago and I didn't notice the pulsing in the rotor until recently. But I am sure I could have bumped it somehow. :icon_redface:

Jeff, see HERE - specifically post #3 and post #10 (thanks to Speedygeezer and Walt)

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Most can be straightened by hand. I use the move it twice the amount bent. Find the middle, or maximum bend and move the correct way. Not as hard as you think.

Let me know, and go in small steps. start with a little and work up to the amount I said. If it is bent 20, move 10 and see if it comes back to 15. Make sence?

Yes this does make sense. Thanks for the suggestion Stan!

Jeff, see HERE - specifically post #3 and post #10 (thanks to Speedygeezer and Walt)

Whoa, thanks for the link, I did search but did not find this tidbit. I am going to try this.

If I did bend the carrier myself (somehow :icon_rolleyes: ) then it make sense that I can un-bend it, right. :icon_surprised: Amazing how weak the carriers are laterally, considering how strong they are radially.

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Boy it is easy to move those carriers. I used a rubber mallet and a 3/4" dowel. I gingerly moved the rotor back into place by tapping on carrier arms as needed. I will have to describe it better later. Got the wow down to .0025in at the worst area.

I did take it for a ride tonight and it seems better. The road was wet so it was kind of hard to tell if I was locking up the wheel on hard stops. It is better, not perfect but better. Thanks for the suggestions guys!

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