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Old 07-21-10, 09:39 PM   #1
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Cleaning Tri-flow off disc brakes?

I absent-mindedly doused my caliper and rotor with tri-flow a couple days ago. I've been trying to wipe it (and the accumulating grime) off with cloth whenever I get the chance, but braking performance from that brake is poor now and has not improved. I'm afraid that, with lube in there, I'm now simply polishing my pads and rotors when I brake. Thoughts/solutions? Thanks.
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Old 07-21-10, 10:07 PM   #2
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Your pads are toast, toss them. Clean your rotor with a degreaser, then wipe with denatured alcohol to remove any residue. Watch the tri-flow in the future
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Old 07-22-10, 06:51 AM   #3
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Second the replace-the-pads. I would also recommend replacing your rotor unless you've got a torch and a steady hand.
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Old 07-22-10, 06:58 AM   #4
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Depends on which tri-flow product. Some of their products are water soluble. Go check on their product site.
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Old 07-22-10, 07:37 AM   #5
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Second the replace-the-pads. I would also recommend replacing your rotor unless you've got a torch and a steady hand.
????
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Old 07-22-10, 07:41 AM   #6
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????
Apparently Severian hasn't heard of solvents The pads should probably go but the rotor can be cleaned with a variety of products...from mineral spirits to brake cleaner.
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Old 07-22-10, 12:02 PM   #7
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ok, cyccommute... I hear your sarcasm and raise you;

Burnishing a disc rotor with an abrasive sheet such as emery cloth to remove any surface glaze, cleaning the rotor w/ Dawn Dish Detergent and hot water, then burning the rotor with a torch to remove any solvents, oils and other foreign material cleans the surface of a rotor with more predictable results. That process allows a mechanic to then (properly) bed in a new set of pads with an existing rotor. The burnish, clean and burn process is one that motorcycle and automotive mechanics use to prep a rotor for a new set of pads. They do this prior to cycling the disc brakes on your car or motorbike before you get it back from them to bed in the pads to the rotor and provide a smooth consistent braking surface. This process is also advocated by Calvin at Park Tool and the techs at SRAM/Avid.

I can almost guarantee you that no end-user of a set of disc brakes, whether on an automobile, motorbike or bicycle, knows the correct procedure to bed in their disc brakes to provide the most consistent braking force with the least amount of flutter and noise.

FWIW; Dawn *is* a solvent, and a damned good one that leaves no residue behind. And it's cheaper than a can of brake cleaner.
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Old 07-22-10, 12:25 PM   #8
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Just clean the rotors and replace the pads,they'll be fine.If they got glazed or "burnished" from the oil,use a red scotchbrite pad or 320 sandpaper to scuff them up a bit before you clean them.

In a perfect world ,you really want an omnidirectional finish on brake rotors.

I've been an automotive machinist for 40 years and that's the first I've ever heard of the torch thing,I suppose that's one way of getting rid of contaminates.

Your not going to burnish anything with an abrasive sheet.Burnishing closes or smears the grain,not open it up.

I just machine the rotor surface CORRECTLY when I do them at work.Never seen anyone in 40 years, torch their rotors before driving them ,on anything.I don't know about Park tool and SRAM but take a look at the Bendix site,they have been making brakes and friction material for 100 years.No mention of torches there.

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Old 07-22-10, 01:11 PM   #9
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ok, cyccommute... I hear your sarcasm and raise you;

Burnishing a disc rotor with an abrasive sheet such as emery cloth to remove any surface glaze, cleaning the rotor w/ Dawn Dish Detergent and hot water, then burning the rotor with a torch to remove any solvents, oils and other foreign material cleans the surface of a rotor with more predictable results. That process allows a mechanic to then (properly) bed in a new set of pads with an existing rotor. The burnish, clean and burn process is one that motorcycle and automotive mechanics use to prep a rotor for a new set of pads. They do this prior to cycling the disc brakes on your car or motorbike before you get it back from them to bed in the pads to the rotor and provide a smooth consistent braking surface. This process is also advocated by Calvin at Park Tool and the techs at SRAM/Avid.

I can almost guarantee you that no end-user of a set of disc brakes, whether on an automobile, motorbike or bicycle, knows the correct procedure to bed in their disc brakes to provide the most consistent braking force with the least amount of flutter and noise.

FWIW; Dawn *is* a solvent, and a damned good one that leaves no residue behind. And it's cheaper than a can of brake cleaner.
FWIW, Dawn isn't a solvent. It is a surfactant. It surrounds nonpolar substances in water with a nonpolar end of a large molecule and presents a polar end to the water in the form of a micelle which can then be dissolved in the water...which is the solvent.

Raiden isn't talking about bedding a new brake but only about cleaning something off the rotor. While fire will do the job, a solvent will do just the same thing without the problems that would be entailed with an open flame...overheating, fire, etc. A solvent like mineral spirits will clean the rotor and not leave anything behind. Can't say the same for burnishing as Booger1 details above.
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Old 07-22-10, 08:09 PM   #10
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Thanks for the replies, guys.

I was lubing my chain, got distracted, rested my wrist (holding the bottle) on the rear tire, and turned my body 180 degrees. My wrist turned, too, and I shot a stream of lube straight into the gap on the top of the caliper. Quick way to waste a set of brake pads

Feel free to continue....
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Old 07-22-10, 08:20 PM   #11
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Holy crap. What are you guys on?
Clean the rotor with isopropyl alcohol and a toothbrush. It will clean up just fine.
If your pads are metallic, you can use alcohol on them too - or a propane torch if you're feeling dramatic.
If they're organic or semi-metallic... you can try swiping them with an alcohol-wet rag, but they might just need replacing.
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Old 07-22-10, 09:00 PM   #12
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I say take off and nuke the site from orbit. It's the only way to be sure.
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Old 07-23-10, 07:48 AM   #13
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Holy crap. What are you guys on?
Clean the rotor with isopropyl alcohol and a toothbrush. It will clean up just fine.
If your pads are metallic, you can use alcohol on them too - or a propane torch if you're feeling dramatic.
If they're organic or semi-metallic... you can try swiping them with an alcohol-wet rag, but they might just need replacing.
Alcohol...of any kind...is not the best choice to remove lubricants. Lubricants are generally nonpolar materials, i.e. water insoluble, and alcohols are polar, i.e. water soluble. Think oil and water. If you want to dissolve the lube and not just smear it around, use a solvent that is nonpolar too. Mineral spirits are nonpolar and will dissolve the lube.
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Old 07-23-10, 11:11 PM   #14
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I've revived contaminated pads and freshened up really used ones using these two simple moves:

1. Clean the rotor with a solvent. I've used rubbing alcohol, methyl hydrate, varsol. I'm sure some are better than others, I seemed to get pretty good results regardless.

2. Clean the pads on the stove. Put the pads braking surface down on a hot element. Step back, turn on fan if you have one. When they stop smoking, take 'em off (use pliers, not fingers!). I've had good luck with Hayes and Avid Jucy pads. Don't touch the braking surface with your fingers when handling the pads.

Good luck!
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Old 07-24-10, 09:25 AM   #15
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... rubbing alcohol, methyl hydrate, varsol....
Rubbing alcohol = isopropyl alcohol or, more properly, 2-propanol

Methyl hydrate = methanol

Varsol = mineral spirits

Mineral spirits is the best on the list. 2-propanol is less good. Methanol is just bad. It won't work very well and it's the most toxic of the 3.
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Old 07-24-10, 10:36 AM   #16
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Good info, thanks! I assumed that they were all alcohols due to the -ol suffix, so I just used the most powerful one (methyl hydrate) that I have on hand. I've always thought of varsol/mineral spirits as "dirty" and likely to leave a residue so I've tried to use something else to minimize this problem.

You'd recommend Varsol for this then?


Not that bicycle disk brakes are that fussy, this isn't a flask in the lab after all, but a hunk of metal wailing around in the dirt.
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Old 07-24-10, 10:50 AM   #17
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Mineral spirits do eventually dry away but it takes a long time. However it IS superb stuff for loosening any oils or greases. But because it does this by just thinning the oils/greases and spreading them around you'll never wipe ALL of it away. That's where the second line of attack comes in if you're trying to totally degrease a surface. And that would be either a liberal hosing down or multiple wipings with a degreasing solvent such as automotive brake cleaner or one of the citrus degreasing detergents or Simple Green.

Solvents are quite a study and we bicycle tinkerers only ever see a small number of the possible options. But there's no doubt that of the entire list the alchohals are by far the weakest and least effective. And as pointed out so ably above it's because of a basic chemical incomaptibility to mix with petroleum products to properly dig into them and flush them away.
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Old 07-24-10, 10:58 AM   #18
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Automotive brake cleaner (CRC Brakleen) will remove brake fluid, grease, oil and other contaminants from brake linings, pads, drums and calipers. It is non-staining, non- corrosive and leaves no residue and evaporates fairly quickly.
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Old 07-24-10, 11:22 AM   #19
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Ah yes, but it is still a solvent that works by dissolving and thinning any oily contaminants. So to ensure that the oils are removed well enough you need to use a LOT of the brake cleaner. When I use CRC Brake Cleaner to clean my rotors I squirt it onto a paper towel and rub the rotors. I turn the paper around and use a fresh surface often. I then repeat this until the paper towel has no signs of oil or grey particle staining. I then clean it ONE more time since the eyeball is a poor judge of truly being clean. The only other way to ensure a clean rotor using brake cleaner is to forcefully hose the rotor down with a quarter to third of the can of solvent so it dissolves and flushes away any contaminants. And that's a rather expensive cleaning job.

These two options for the one product is an example of what I mean about knowing and correctly using a product with a suitable method.
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Old 07-25-10, 09:45 AM   #20
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Mineral spirits do eventually dry away but it takes a long time. However it IS superb stuff for loosening any oils or greases. But because it does this by just thinning the oils/greases and spreading them around you'll never wipe ALL of it away. That's where the second line of attack comes in if you're trying to totally degrease a surface. And that would be either a liberal hosing down or multiple wipings with a degreasing solvent such as automotive brake cleaner or one of the citrus degreasing detergents or Simple Green.

Solvents are quite a study and we bicycle tinkerers only ever see a small number of the possible options. But there's no doubt that of the entire list the alchohals are by far the weakest and least effective. And as pointed out so ably above it's because of a basic chemical incomaptibility to mix with petroleum products to properly dig into them and flush them away.
Mineral spirits evaporates very quickly. It is about on par with isopropyl alcohol. A 5 to 10 minute wait after application is about all it takes for it to evaporate.

Mineral spirits don't just 'loosen' oils and grease nor does it just thin them out or just spread them around. Depending on the amount used...and the amount needed would be very small...it dissolves the oils and greases and removes them. Commercial parts washers use odorless mineral spirits to degrease parts.

Brake cleaners might do a better job but they cost more and are more harmful to the user and the environment. Citrus degreaser and all other water based degreasers don't do a better job...if you measure better by volume of degreaser needed to do the job. Citrus degreasers are surfactants and surfactants are great for washing clothes but they are only marginally effective against heavy grease loads.

If you want the brake rotor surface really clean, remove the bulk of the contaminate with a rag soaked in mineral spirits (soaked doesn't mean dripping), then flood the rotor (or the effected area) with clean solvent. Place the rotor in a hot sunny place for 10 to 20 minutes for the mineral spirits to evaporate ...just to be sure. Then reinstall.
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Old 07-25-10, 09:53 AM   #21
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Get some brake cleaner that's used to clean car rotors. It was good enough to get ATF off my Subaru's rotors, and it will be good enough to get Tri-Flow off of your bicycle's rotors.
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Old 07-25-10, 11:49 AM   #22
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Mineral spirits evaporates very quickly. It is about on par with isopropyl alcohol. A 5 to 10 minute wait after application is about all it takes for it to evaporate.......
The low odor paint thinner mineral spirits I get from the hardware store takes a good couple of hours to dry away unless the surface is wiped clean so there's only a very thin layer of the spirits left. The solvent is much like Varsol cleaning solvent in this manner. Maybe your stuff is something a little further up the petrochem food chart?

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.....Mineral spirits don't just 'loosen' oils and grease nor does it just thin them out or just spread them around. Depending on the amount used...and the amount needed would be very small...it dissolves the oils and greases and removes them. Commercial parts washers use odorless mineral spirits to degrease parts......
You may want to try dissolving some grease in your mineral spirits and then spread out the result on a clean sheet of metal or glass. Once the solvent evaporates away you're left with the same original amount of grease or oil that was originally mixed with the solvent. It doesn't remove the stuff at all other than by flooding the part with clean solvent. This is the nature of solvents, they dissolve the oil or grease in this case into a solution but the oil or grease is still there but spread around in the solution. The only product that lifts and encapsulates an oil or grease as you're suggesting is a detergent. So if only a small amount of solvent is used to clean a part then it is wiped off the residue left behind will be a solution of some solvent and some of the original contaminant. Hence the need for repeated solvent washings to remove a little more of the grease or oil with each wash. The parts washer you mentioned will only do a nice job of degreaseing when the solvent is new and fresh. Once it has been used for a while and it's an amber color from the grease and oil held in solution it does a very nice job of leaving a light coat of oil/grease as a rust preventative film once the solvent dries away.

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If you want the brake rotor surface really clean, remove the bulk of the contaminate with a rag soaked in mineral spirits (soaked doesn't mean dripping), then flood the rotor (or the effected area) with clean solvent. Place the rotor in a hot sunny place for 10 to 20 minutes for the mineral spirits to evaporate ...just to be sure. Then reinstall.
Now we're talking! This will certainly work as mentioned but it contradicts what you wrote in the first part.
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Old 07-25-10, 09:35 PM   #23
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The low odor paint thinner mineral spirits I get from the hardware store takes a good couple of hours to dry away unless the surface is wiped clean so there's only a very thin layer of the spirits left. The solvent is much like Varsol cleaning solvent in this manner. Maybe your stuff is something a little further up the petrochem food chart?
I doubt very highly that it takes a couple of hours for mineral spirits to evaporate from any surface unless the surface is submerged below several inches of the liquid. The vapor pressure of mineral spirits...even odorless ones...is just too high. If mineral spirits took that long to evaporate, it's be hard to ignite like diesel fuel. While mineral spirits that contain aromatics, i.e. odored mineral spirits, are more volatile and flammable than odorless, you can still ignite the odorless kind very, very quickly with effort.

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You may want to try dissolving some grease in your mineral spirits and then spread out the result on a clean sheet of metal or glass. Once the solvent evaporates away you're left with the same original amount of grease or oil that was originally mixed with the solvent. It doesn't remove the stuff at all other than by flooding the part with clean solvent. This is the nature of solvents, they dissolve the oil or grease in this case into a solution but the oil or grease is still there but spread around in the solution. The only product that lifts and encapsulates an oil or grease as you're suggesting is a detergent. So if only a small amount of solvent is used to clean a part then it is wiped off the residue left behind will be a solution of some solvent and some of the original contaminant. Hence the need for repeated solvent washings to remove a little more of the grease or oil with each wash. The parts washer you mentioned will only do a nice job of degreaseing when the solvent is new and fresh. Once it has been used for a while and it's an amber color from the grease and oil held in solution it does a very nice job of leaving a light coat of oil/grease as a rust preventative film once the solvent dries away.
You've just described a physical separation of a solvent and a solute. I do it all the time at work. I have better ways of controlling the evaporation of the solvent and recovering the solute but it is essentially the same. But that has nothing to do with cleaning the surface. If you put the solvent on and then just let it evaporate, you won't remove the grease. But that isn't what I've been suggesting. Removing the bulk of the contaminant with solvent on a rag and then switching to a clean rag with fresh solvent or flooding the area with solvent will remove the grease. It dissolves it and traps the material. As long as you don't let the solvent evaporate in place, the contaminate will be removed.

Detergents aren't the only way to remove grease. Fresh solvent will do the same job. That why brake cleaner is in aerosol cans...lots of fresh solvent. But, for a small surface like a bicycle brake rotor, you can do as good of job as you need to with a very small amount of solvent.

Additionally, if you leave the detergent in place, you'll end up just as you would if you let the solvent evaporate. The micelle only works if there is water around to keep it as a micelle. Evaporate the water, i.e. don't rinse the soap off, and the grease will still be there. It's somewhat self-explanatory that more then one step is needed when using a solvent, if the goal is to completely degrease the part. If you were dumb enough to have enough grease on a brake rotor to need a parts washer to remove it, a rinse in clean solvent after using the parts washer would be as sensible as rinsing with clean water after using a water-based degreaser.

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Now we're talking! This will certainly work as mentioned but it contradicts what you wrote in the first part.
I see nothing that contradicts what I have written previously. I didn't include details on how to do it but as I said before it seems rather self-explanatory.
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Stuart Black
New! Pokin' around the Poconos A cold ride around Lake Erie
New! Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
An Good Ol' Fashion Appalachian Butt Whoopin'.
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