I would take a hard look at your front master cylinder, sounds like the piston is not returning and leaving the system pressurized.

 

Right.First check ,,Freeplay " of the brakelever.Is there any next remove the lever and check piston comes back.clean it with brake cleaner and put lever back.Attention:theres a nub who push the brakeswitch.
Dont ruin em ...))))

Brake calipers:
Remove brake pads and clean the area around the pistons with brakefluid or WD40.Push back the pistons and pump em out a little.
Brakecaliperproblems come up at mor than 50k miles or so.

 

Well, I started out with draining the brake fluid because the problem stayed after cleaning the calipers (brake cleaner and tooth brush) and applying a bit ceramic grease to the pistons.
I had called the local speed shop owner, who's a friend of mine, and he said it could be corrosion on the pistons between the two seals, so I decided to just take them apart.
When I took the RH brake line off, I noticed iron in the oil that came out of the caliper. And upon removing the pistons, I could see a lot of iron particles in the caliper halves.
I've changed the brake oil 4 times since I bought my bike (new) and never noticed iron in the oil that came out.

It may not be the reason for my brake problem, but I'm glad I took the calipers apart. Iron particles don't belong in hydraulics.

 

Okay.

The pistons are plated,chrome or nickle,whatever.I know these calipers from Triumph & some Japanese bikes and had a few in parts.
Its possible pistons having rust after plating has gone partially at the sealing area.
Theres no iron at all in the calipers.Maybe you find chips from the plating.
Possible this ..Iron" comes from the top,the spring in the pump can brake and parts rusting awhile.
After they fal into the system.Never seen this before but......................

So put the pump in parts or get a new one.I dont know if there is a rebuild kit availabel and its a job for a Pro.
Repair kits for the calipers you will find on flea-bay.Pry the pistons out,one by one, and check for wear.You can block the other pistons by a piece of wood ,no metall.
When the plating has be gone think about a new set of calipers because the complete set of parts maybe killing your purse.
If pistons okay polish em .Put em back in the caliper .Its NO good idea to use any other grease or whatever.!!!Use brake fluid.

The main problem is the DoT4 or 5.1 fluid .
Attention.DoT5 is Silikcone fluid.DoT5.1 NOT.
If water comes into the system rust is the result.Nobody draining his brakesystem regulary.
These XR,s are near 10 years old so parts will go away.

 

Thanks for the reply.

Just took the left caliper apart and as soon as I removed the banjo bolt, I found these inside:

And while taking the whole thing apart it was just like yesterday. More metal flakes and grime.

Master cylinder will be next to take apart.

It seems to me that someone forgot to clean the parts after they were machined in the factory...

 

Pistons are coated,not plated.Good.Clean all the part and rebuilt with a set of new Rings.Flush the pump only and try to get back on the road.Brown debris shows Water inside the system.A common problem of braksystems with DoT4 fluid.
Changin the fluid leaves the debris/water at the bottom of the calipers.a timekonsuming procedere to rebuilt the Brakes.
A shop will take 300,-$.............................good Luck.

 

So you think I don't need to take the M/C apart?

What worries me most is that those big flakes can easily block the ports to the brakes, which are about 2mm diameter. And no way to drain those flakes out since the bleeder holes are about the same size.

 

For my opinion and to keep the cost low or the job short clean the M/C.If you look inside the bowl you will see no chips.So flush the M/C and finish the job.Maybe you find a microscope to detect wat kind of chips you find.
Im not shure but there was a information if the system is in parts clean all the parts and use the DoT5,SILIKONE,Fluid.Check some Forums or google.
Dont mix the fluids.

 

So, been trying to find a fitting seal set with the speed shop owner this afternoon. We ordered a rebuild set for a 1999 CBR600, since it also has the same brake pads. If might just be the same set of seals also.
The HD rebuild set is stupid expensive at 160 euro per caliper and includes the pistons, which I don't need.

I'll keep this topic going and will post info as I have some for further reference as to what seals fit.

 

These calipers are very common on diff. bikes like Triumph and some Japs.Lookin for brake pads will tell you more....)))).
Keep us informed.

 

My rear seems to be dragging a touch more that others I’ve had (Japanese, Euro) I thought it might be a HD thing.
Are everyone else’s wheels spinning freely?
Ill be watching for more info on your rebuild. Thank you.

 

Dragging on ther rear is common.If you think its too much push the piston back 2 x,it works for a while.Racepads with more metal will create some more noise as the organics.
When the pads are out its a good idea to clean the caliper,first brake cleaner,after hot water and a toothbrush and then push piston & pedal a few times.After all change brakefluid and force the pedal twice.

 

Is it the brake that is dragging, or is it the belt's resistance that you feel?

 

Good one:

I m also not happy with the rear belt setting information from the manual.Knowing the Buells,they allways had a lash belt the XR and other Harleys come along with a tight belt.This forces the bearings to hard.So use your fingers and some experience to set the belt right.
A ,,Humming""feeling in the seat and the A...s.e says at normal speed,belt is to tight.
Im always settin the belt like if it turns 90° in the lower trum its okay.The bike feels softer in the gears at any speed.Use some Beltspray with Teflon and the belt runs smooth.Theres no SQUEEKING noise when handle the bike in the garage.

 

As long as the belt isn't skipping teeth you cant run it too loose. The first thing EVERY Harley guy looks at is my belt, I run it super loose because I also run the hell out of the bike and being on one wheel in a power wheeley or all g-forced out in a turn will raise the swingarm up high tightening the belt considerably. Seriously, don't stress to much on how loose the belt looks, be much more worried about it being too tight.

The absolute best way to tighten the belt to the BEST standard would be to unbolt the rear shocks with the bike on a lift and jack the rear tire up till the swingarm is in the straight back position THEN adjust it to Harley specks. 12Lbs of pull down to the required deflection if I remember correctly. Then rebolt the shocks and measure the pull down lbs to the correct deflection and write it down somewhere. Just an idea.

 

So finally some time to add a few things to this topic that could help people who need to change the seals.

The calipers have also been used on Honda CBR600 bikes for example, so the seals I used are original Honda parts.

The big piston's seals are PN 06451-961-405
The smal piston's seals are PN 06451-166-405

Each pack only holds 1 set of seals: 1 dust seal and 1 piston seal. You'll need 2 for each caliper.


And it may be worth to take the calipers apart when the bike is 7 years old, like mine. Or at least take off the brake lines and leave the calipers upside down over night to drain all the water.
Even when changing brake fluid every year, like I did, there was only water in the caliper with a tiny bit of brake fluid in it (and metal shavings). I believe this is basically due to the fact that the bleeder nipple is ABOVE the brake line fitting, and the brake fluids weighs less than water. The water drops into the caliper and can never be flushed out. I use an SBS brake bleeder that uses compressed air to suck out all fluids, and yet the water never got sucked out.

 

Is it all sorted out? Did the rebuild stop the original problem of the pistons not returning?

 

Yes, all is good now.

 

:clap:

 

Just to start this frikkin topic again, rh disc is hot after a ride, lh just a bit warm. To the problem is back.
There has to be at least one piston not returning after releasing the brake.

Or could this have something to do with different lengths of brake lines of the Free Spirits kit?

 

A front caliper release problem wont have anything to do with the brake line length.

 

I just don't know where to start looking. Calipers have been thoroughly cleaned with brake cleaner and a soft tooth brush, new oil and dust seals, a tad of brake fluid on the pistons and seals before assembly, they all slid in place smooth (the small pistons a bit harder). Left caliper is fine, right is not.

I guess there's nothing else to do but to tear it down again.


But maybe, just maybe, those Honda seals are just a tine bit too thick for the pistons?

I'm going to start with the M/C first and go from there.

 

No big deal.Remove the pads and Spray some WD40 on the Pistons or Brakefluid.Force the Pistons in and out and the Problem will be gone.

 

First thing I would do is lift the front tire off the ground and see if it is free spinning. If it is then the cool rotor either has slipping pads that have some fluid impregnated in them or that caliper isn't clamping correctly and the other rotor is doing double duty.

Sent from my SAMSUNG-SM-G870A using Tapatalk

 

First check was spinning the wheel with only one caliper installed. Left was as it should be, spinning free and stopping the wheel as it should be. The right was always dragging a bit (aprox 1 turn before the wheel stopped because of it), but braked normally.
Then checked and took apart the M/C, it still had a few tiny metal flakes in it. Cleaned it up, checked for burrs and reinstalled it. That big clip is a pain in the but btw...
Then I just figured I might check the right caliper again. Disassembled the whole thing again, checked for burrs, rub marks on the pistons, checks if the nipple passage is clear, checked al other passages in the caliper, cleaned, dried with compressed air, checked pistons for wear again, cleaned the seals and checked them, didn't put any oil or grease on the when I put them in, just al very light coat of ATE grease (specifically for brake parts/pistons/seals,...) only on the oil seal and a light coat on the radius of the pistons. All went together easily.

Today I'm going to refill the brake system and see what happens.

If it's still doing the same thing, I think there might be just a tine difference between the HD seals and the Honda seals.