anyone have a runout gauge?

[scubasteveRR]

Any one here have a runout gauge to check if I have warping in my brake rotors?

I have a slight pulsating in them and I want to check them out while there's still snow on the ground so if I need to get the straighted I can.

[Rambunctous]

Yes I do. You could also check em with a flat edge steel ruler. But I do not have a press to try to bend them back.

[scubasteveRR]

Super and you are close to me... do the rotors have to be on the bike to test them with the gauge or do you take them off to do that? I have no idea how the gauge works.

If they are warped I plan on sending them out to this guy... http://willsrimrepair.com/ he does rims and rotors.

[Paul_E_D]

Rotors don't usually bend. Just the carriers. A crude way to measure this is just to put the front up on a stand and set up a pointer like 1/4 inch from the disk and spin the wheel. You can eyeball the runout. If you can see it, it's causing pulsing.

A little tapping on the carrier with a 4lb mallet can "fix" the issue to a large degree.

[obsolete]

A crude way to measure this is just to put the front up on a stand and set up a pointer like 1/4 inch from the disk and spin the wheel. You can eyeball the runout. If you can see it, it's causing pulsing.

Quick cheap and easy.

[scubasteveRR]

Rotors don't usually bend. Just the carriers.

So how do I chcek the carriers??


HMMMMM. well basically i have some rubbing of the brake pad on the rotors only in certain places and some very slight pulsating when I'm braking. It's was nothing crazy that made me stop riding the bike at the time but you can feel it in the bike when you are at slow speeds so I wanted to sort that out over the winter.

my first plan of action was to take off the rotors and clean the rivits really good with brake cleaner and a brush to get all the dust out of them and see if that fixes my issue. If not I was going to check to see if they were warped at all with the gauge and send them out to be straighened if they were since the rotors only have 10k on them.

does this sound like a good course of action to check the issue?

[brendanp]

+1 to what Paul said, but any runout in the wheel will also be transferred to the disc.

[Speed Demon 828]

I don't know guys. I've been in the motorcycle biz for 15 years. Most of those as a tech and I've never heard of straightening a bent rotor.

The quickest way to check is with a straight edge and feeler gauges or take the rotor off and put it on a flat plate.

But I would never try to bend one back

I mean I could be wrong about trying to bend them back but I have never heard of anyone that has done it.


edit
I just reread Paul said to tap on the carrier. That would work I guess.

[Paul_E_D]

You don't check the carriers, you check the disks as I described. Fix a pencil or something pointing at the side of the disk and spin the wheel. You might need someone to hold the bars steady.

Find the high spot and tap the carrier at the nearest button.

Rinse and repeat.

So how do I chcek the carriers??


HMMMMM. well basically i have some rubbing of the brake pad on the rotors only in certain places and some very slight pulsating when I'm braking. It's was nothing crazy that made me stop riding the bike at the time but you can feel it in the bike when you are at slow speeds so I wanted to sort that out over the winter.

my first plan of action was to take off the rotors and clean the rivits really good with brake cleaner and a brush to get all the dust out of them and see if that fixes my issue. If not I was going to check to see if they were warped at all with the gauge and send them out to be straighened if they were since the rotors only have 10k on them.

does this sound like a good course of action to check the issue?

[Rambunctous]

Are they floating rotors? Are they floating okay? Are the calipers rusted in position? As speed demon says use a flat plate. I also have a piece of plate glass that I use to check cylinder heads.

[Rambunctous]

And what you want if using a gauge is called a dial indicator.

[scubasteveRR]

I'm just trying to rule out any warpage in my rotors, I can't tell what the issue is but I'm pretty sure there is something going on that is causing the pulsating feeling... NOTE: The pulsating doesn't transfer into the brake lever but i can feel the pulsating in the bike at it comes to a stop or if I am braking at slow speeds?

I don't know guys. I've been in the motorcycle biz for 15 years. Most of those as a tech and I've never heard of straightening a bent rotor.

http://willsrimrepair.com/ I found this site onthe WERA forum and there were a lot of perople who chimed in and said they sent thier rims & rotors to this guy and he straightened them out?

You don't check the carriers, you check the disks as I described. Fix a pencil or something pointing at the side of the disk and spin the wheel. You might need someone to hold the bars steady.

Find the high spot and tap the carrier at the nearest button.

Rinse and repeat.

I'd be hesitant to tap my rotors/carriers with a hammer since I am afraid of warping it even more if it is even warped.

[Paul_E_D]

This is a racer's technique. I fully understand that a tech would never do it. But money is hard to come by and you learn to do what works in the crucible of racing.

I've never heard of straightening a disk. You could certainly pull it off and check it for flatness, but it will likely be flat.

The "floating" buttons do not float enough to eliminate pulsing caused by a tweaked carrier. Another racer's trick is to remove the spring washers from the buttons so that the disks truly float. This can ease the pulsing problem, but makes your brakes rattle.

[gamorg02]

let me know if you need any more help. i work in westboro and have a indicator i could bring up, has a vice-grip type clamp system.

i dunno what your guys personal specs are, but i know galfers is no more than 3 mils of runout. my galfer rotor after 1k miles had 7 mils of runout when measured on the bike, i sent it to 'em and they replaced it even though they saw 2.5 mils.

[scubasteveRR]

Are they floating rotors? Are they floating okay? Are the calipers rusted in position? As speed demon says use a flat plate. I also have a piece of plate glass that I use to check cylinder heads.

I do not believe they are floating rotors, they are stock 2005 600rr rotors.

I haven't taken the calipers off yet but I plan on doing that, cleaning them out really well and replacing the brake pads incase this is were the issue is comming from. I figured I would get all my ducks in a row and have a plan before I started taking it all apart.

I guess I can just take the rotors off and check them with a metal ruler, i just figure using a gauge would give me a more accurate reading.

Should I take the rotor out of the carriers before I check them since the carriers could be causing the rotors to not be straight?

[Paul_E_D]

Where's that picture of the Ducati factory race shop? The one where the only tools visible on the bench are hammers?

[scubasteveRR]

one more question, what should I use to clean my calipers? I was planning on using some brake cleaner and tooth brush? Once they are clean do the pistons (or anything on the calipers) need to be lubed in anyway.

[FireboltEric_MA]

Low speed pulsing usually means warped rotors, if that is the case chuck em and get new ones.

If it is the wheel, I would send them out for fixing (a little over 100 bucks usually)

I wouldn't be "Fixing" anything on there with a hammer.

If the carriers are warped, I would expect the rotors to be the same. Cant see how one would warp and not the other.

Keep in mind I am only guessing here.

[Paul_E_D]

Brake cleaner, then a light scrub with emory cloth(400-600) or scotchbrite, then brake cleaner.

No lube near the brakes. There is such a thing as lubricant for the pistons, but you only use a tiny bit. Most don't use it as it's possible for it to get on the pads/disks when things heat up.

[Paul_E_D]

Sorry, you're guessing wrong. Rotor are very very hard steel or iron. Carriers are cast aluminum. One little bump into a chock, or a bad trailer setup and they are tweaked.

Low speed pulsing usually means warped rotors, if that is the case chuck em and get new ones.

If it is the wheel, I would send them out for fixing (a little over 100 bucks usually)

I wouldn't be "Fixing" anything on there with a hammer.

If the carriers are warped, I would expect the rotors to be the same. Cant see how one would warp and not the other.

Keep in mind I am only guessing here.

[gamorg02]

Sorry, you're guessing wrong. Rotor are very very hard steel or iron. Carriers are cast aluminum. One little bump into a chock, or a bad trailer setup and they are tweaked.

you would expect a constant friction noise then right, if the carrier was off, not spot noises? Every bike i've had makes some noise when spinning the tire in spots, but imo pulsating - replace disk

[Paul_E_D]

Whatever guys. I guess I have learned nothing in 10 years at the track. Spend away!

Low speed pulsing would NEVER get my credit card out.

To each his own.

[Speed Demon 828]

Didn't he say he couldn't feel the pulsating at the lever.


Me thinks you might have a different problem. Check the rotors make sure they are good-clean everything and then road test. If there is no pulsating at the lever you have a different problem.

[gamorg02]

Whatever guys. I guess I have learned nothing in 10 years at the track. Spend away!

Low speed pulsing would NEVER get my credit card out.

To each his own.

didn't say that, just said what i would do.

Didn't he say he couldn't feel the pulsating at the lever.


Me thinks you might have a different problem. Check the rotors make sure they are good-clean everything and then road test. If there is no pulsating at the lever you have a different problem.

i think he said he could feel it.

[scubasteveRR]

Whatever guys. I guess I have learned nothing in 10 years at the track. Spend away!

Low speed pulsing would NEVER get my credit card out.

To each his own.

See this is my point, I don't want to spend $600 on a new set of rotors or buy a used pair.

I rode all last year (about 7-8k miles) with it and the the bike stops perfectly fine. I feel like there is something that is tweaked somewere causing my issue and before I spend $ I figured I would exhaust my options first.