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Discussion Starter #1
This season I've noticed a problem with my front brake lever that seems to be getting progressively worse.

When I apply the brake and then release it, there's a pause before the lever rebounds to it's original position.

The only work I've done on the front brakes is installing speed bleeders and replacing the fluid over the winter. After a few weeks of riding this season, I noticed the problem and redid the brake bleed, thinking maybe I let some air into the system. That improved the situation for a little while, but it's started getting worse again. Now it's to the point where I have to manually push the lever back into place after braking. The brakes, however, appear to be working fine.

Additionally, my ABS light has been going on and off for a couple of weeks, and it's been continually on for about a week now. I don't know if these are related, but thought it was worth mentioning.

All ideas welcome.
 

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The area around the front sprocket fills up with sludge. Take the cover off, clean the area up and most likely the problems will go away.
 

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Lube the lever pivot and where the lever contacts the master cylinder piston.

Has your ABS still be working when the light was out?

The ABS sensors do collect crud and at times that may impede proper signal. Take them out (8mm socket) and clean the surface that looks towards the ABS ring. See if that helps.

Do you run stock size tires or any non stock dimension tires by any chance? The ABS does not like that.
 

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Discussion Starter #4
I'm not sure what "front sprocket" refers to -- any clarification?

The ABS is not functioning when the light is on. I did check the ABS sensors and they seemed OK, but I did try to clean them off anyway.

I swapped stock Trailwings for Shinko 705s a couple of years ago. That hasn't had any impact on ABS before the last 1-2 months.
 

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Remove, clean and lube the brake lever. And the actuator part of the master cylinder. Ensure that the lever moves freely after you reinstall it. The speed bleeders should make no difference, nor should removing the countershaft sprocket cover and cleaning that gunk out.
Clean the brake disks with brakeclean, and as blaustrom says, inspect and clean the ABS sensor and the ABS ring.
If the brake lever still binds, remove and inspect the brake pads.
 

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The problem is with the leaver or the master cylinder. (MC)

The callipers, discs & ABS should play no part in the return of the MC plunger/piston assembly.

The return spring in the MC should have enough force to have the leaver return to it's original position.

Over time the leaver and the pivot pin will wear down, have a good look at both it could be time to replace them, the hole in the leaver and the pin will become oval not round.

There is a rubber boot covering the MC plunger/piston where the leaver meets the plunger/piston, ensure it is in good condition and sliding well so as not to limit the plunger returning.


If you still have the problem there is a return fluid port in the MC, this is to allow the pressurised fluid to return to the MC when the you release the leaver, there could be crud built up and restricting the ports.

If you had a reason to change the fluid in the first place like poor brake performance it could all be linked back to the condition of the MC.
 

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I'm not sure what "front sprocket" refers to -- any clarification?

The ABS is not functioning when the light is on. I did check the ABS sensors and they seemed OK, but I did try to clean them off anyway.

I swapped stock Trailwings for Shinko 705s a couple of years ago. That hasn't had any impact on ABS before the last 1-2 months.
Sorry, I thought you were talking clutch.

Front, pull the calipers and clean the area between the pistons and the caliper.

Here they use a very fine gravel on new seal and creates little hard centered balls of tar than get stuck in that gap. Personally I use a small screwdriver and work it around being careful not to poke the seals or scratch either surface.

However the ABS not working is not a good sign. I've had issues with the ABS, getting the brakes working as well as I could then doing a LOT of hard skiddy stops on wet grass got the ABS functional once more.
 

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As above, check the caliper carefully. Make sure it moves easily in and out smoothly. Clean and lightly grease the boot and pin. Check the disk as well. A caliper that is no longer moving in and out freely will result in rapid pad and disk wear. It happened to me recently on a different vehicle. I replaced the discs and pads only to have the bound up calipler ruin the new disc and pads. All this is a good idea as general maintenance when replacing pads.
 

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Discussion Starter #9
I'm looking to check the master cylinder and brake lever this week. Is this something I can do with everything still in place, or is this more in line with a MC rebuild (something I've done before)?

Also, on a somewhat related note -- how do I know if I have stainless brake lines or not?
 

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I'm looking to check the master cylinder and brake lever this week. Is this something I can do with everything still in place, or is this more in line with a MC rebuild (something I've done before)?

Also, on a somewhat related note -- how do I know if I have stainless brake lines or not?
It's most likely just the brake lever pivot needing lube, so do that before anything else.

On the brake lines, just look at them. Are they rubber or braided stainless steel?
 

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Don't touch the MC. Just take the brake lever pivot bolt out, lube that pivot and the contact area with the MC piston and re-assemble. Should do the trick.
 

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Cleaning and lubricating the leaver can easily be done in place if you need to inspect the internals of the MC that would be easier removed from the bike.

Moisture build up in the fluid over time will cause rust & corrosion stopping things sliding as they should.

I have just opened up the MC on my 1988 R80rt BMW and I found a teaspoon full of crud on the piston even though it seemed to be working fine.

2 screws and a circlip has the job done, then bleeding of course.
 

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Discussion Starter #13
You folks are awesome!

It turned out to be the brake lever pivot after all. I lubed it up and all is good.

As for the brake lines, the reason for my question is that I replaced brake lines on my Concours a few years ago and went with stainless lines. The ones I got were coated with a black sheath so they weren't obviously steel lines when you looked at them. The lines on my Strom are black, but the previous owner was the sort that he would have likely installed steel lines. I wanted to see if there's a way to determine that if they're not obviously steel. I can't find any writing on the brake lines.
 

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Great, now go and lube the clutch lever and the barrel end of the clutch cable that is inserted into the lever (not the cable, its Teflon coated).
 
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