Time to Clean the Front Dual Brake Calipers

[The Mindless Philosopher]

Now that I have addressed/corrected a few minor (i.e. not very time-consuming) issues, the time has come to pull off the front brake calipers and clean them.

I will start with the right side since I suspect it is dragging. The right rotor heats up more than the left, and I hear an occasional metallic groan. I originally thought this was a bearing problem (replaced less than 1,000 miles ago), but I'm not really seeing or hearing any solid indications, especially when testing with the front wheel off the ground.

Both front brake assemblies (Wilwood) are 3 or 4 years old and have less than 20,000 miles on them, but I commute in the desert. Sand gets into everything.

I hope this resolves the problem. The old right side caliper dragged horribly. The right rotor was warped and bowl shaped when I bought the trike. It had cut into the caliper.

If the problem persists after cleaning the new setup, I will replace the front brake lines then go from there. I replaced the front master cylinder at the same time as the discs, rotors, and pads. All that's left are the lines and the T-fitting between the two sides.

I will update this thread with my progress in the days to come.

[The Mindless Philosopher]

Soaking the trike's right front brake caliper in some scalding soapy water (dish soap). Will take a toothbrush to the brake pistons soon.

I love these Wilwood quick release rotors! It makes getting the pads out and removing the rotors a breeze! Only a few seconds.

[The Mindless Philosopher]

No weird deposits or discoloration in the master cylinder (DOT5). Fluid level is good.

[The Mindless Philosopher]

The pistons extended a few millimeters (maybe 3/32 of an inch?) when I started scrubbing them with mild soap and hot water. They look pitted (tiny dark dots) around the areas that were exposed when they extended. So small it's hard to tell for sure. Likely normal abrasions from regular use?

[The Mindless Philosopher]

The tiny dark dots turned out to be stubborn road grime.

The pistons retracted nicely after I re-attached the caliper then inserted the pads. Everything went back together with no trouble at all! I love these Wilwood quick-change calipers!

Will road-test later.

[The Mindless Philosopher]

Cleaning the brakes didn't solve the mystery of the hot right rotor. It still heats up more than the left. At least it's not changing colors from the heat, and it cools down quickly.

This is almost shaping up to be something I'm just going to have to live with.

[Foose1986]

Is the rotor warped? Have you checked flatness of it? An easy test may be to use some blue machinists dye and cover the face of the rotor. Take it for a short test drive and don't use your front brakes. If the dye is worn off in spots, it'll show you that it's warped. I'd suspect this especially if they've gotten hot before.

[rocketsteve]

Also... there are 10 Bobbins holding each disc to the inner disc mounting plate.
These Bobbins keep the disc floating and need cleaning out with Disc Cleaner as they get bunged up with pad and road grime then stop the discs from floating.

My BH is bagged for the winter now so I can't see the front wheel - but somehow you need to turn each Bobbin while spraying in the Disc Cleaner so all 10 on each side turn easily.

If this hasn't been done for a while, you should see a load of crap dripping out of the Bobbins when spraying and rotating.

[The Mindless Philosopher]

Also... there are 10 Bobbins holding each disc to the inner disc mounting plate.
These Bobbins keep the disc floating and need cleaning out with Disc Cleaner as they get bunged up with pad and road grime then stop the discs from floating.

My BH is bagged for the winter now so I can't see the front wheel - but somehow you need to turn each Bobbin while spraying in the Disc Cleaner so all 10 on each side turn easily.

If this hasn't been done for a while, you should see a load of crap dripping out of the Bobbins when spraying and rotating.

No floating discs on this one, just old style 11.5 inch Harley-Davidson rotors (single plates) bolted to the wheel.

[rocketsteve]

Hmmm... back to Foose then

[The Mindless Philosopher]

This video perfectly illustrates what I was getting from my front wheel when it was off the ground and I turned it by hand. No bearing noise as the video title seems to suggest, but brake rubbing.

https://www.youtube.com/watch?v=qArTl1kdb5E

I have since cleaned the brakes, but it appears to have had no effect.

Most of the brake components are somewhat new (around 10-15K miles on them) including the hand control. The only parts I have not replaced are the brake lines and the T-fitting.

I will add that my front tire was unevenly worn before I added the Dyna Balance Beads. I got tired of the lead weights falling off the rim. BUT...only one rotor is still heating up more than the other even after thorough cleaning with expected behavior during cleaning and reinstallation.

Having ZERO prior experience, this has me baffled. I don't mind a hot rotor as long as it doesn't howl, turn colors, or warp. Maybe it's already warped and I just can't see it?

I am not yet convinced this has anything to do with bearings. Still looking into it. The bearings were replaced less than 1,000 miles ago. Don't know what method they used (gently pressed or monkey-hammered??? Done at Harley-Davidson dealership).

[The Mindless Philosopher]

The more I think about it, the more I'm tempted to declare this a (slightly) warped rotor.

[Foose1986]

A dial indicator with a magnetic base would also help check the rotor without removing it. If you know of anyone that has one it'd be a quick thing to try.

[The Mindless Philosopher]

A dial indicator with a magnetic base would also help check the rotor without removing it. If you know of anyone that has one it'd be a quick thing to try.

I'll ask around. Thank you.

[The Mindless Philosopher]

The right front brake pistons are definitely inconsistent in retracting though they are relatively new, have been cleaned thoroughly, and still have good seals. The master cylinder/hand brake assembly is new and still in prime condition, too.

I am now wondering whether I should turn my attention to the T-block that splits the brake line to the left and right calipers. I wonder whether the right side is contaminated with a bur of some kind and partially clogged somehow or if perhaps I should just yank out the T and install a Y-block instead so the fluid path is not so angular?

A sticking right caliper pre-dates the reservoir and caliper replacement, so it seems to make sense. The old caliper had caused the rotor to warp like a bowl and cut into it.

[Paul H]

Just a thought to check the flow to the
2 brakes, Y not have someone pull the
brake lever while you open BOTH bleeder
at the same time??? Then you'll know if
you're getting proper flow to both brakes.
Also, Y not blow out the brake piston
with air and fine sandpaper it down.
You could also lightly run a fine file
around the out side of the piston to check
for high spots???

Paul H

[The Mindless Philosopher]

Just a thought to check the flow to the
2 brakes, Y not have someone pull the
brake lever while you open BOTH bleeder
at the same time??? Then you'll know if
you're getting proper flow to both brakes.
Also, Y not blow out the brake piston
with air and fine sandpaper it down.
You could also lightly run a fine file
around the out side of the piston to check
for high spots???

Paul H

Someone suggested the front brake lines could be too old (I have not replaced them) and might be collapsing/constricting inside the braided shielding. That bleed test you're suggesting could certainly reveal that.

Thank you, Paul!