Brake lever problem, it "stiffens"?

[MeeLee]

I had the same issue on my GS500.

I put some WD40 on the master cylinder, and it fixed my problem.
Make sure you use the straw, to get the oil very localized behind the lever and between the rubber.
It took a few hard squeezes for the oil to spread.

My theory is that the brake oil is somewhat acidic, and causes rust on the master cylinder.WD40 took care of that issue in my case.

[DevilDesire]

I'll take the whole lever off the bike, clean the pivot bolt again but with WD only, because last time I also greased it. Then I will spray the master cylinder thoroughly from all sides and reassemble.

[MeeLee]

Wd40 is 'creepy'.
just as long as a little can find its way to the cylinder, it'll creep in the cracks as you pump the brake. My front brake is working well now.

[sledge]

If the lever is stiff on the pivot when you pull it slowly why is it free when you do it quickly???
Surely its either free or it isn't 

I think all the possibilities have been covered but its difficult to say exactly what's wrong without  some investigating.

If you decide to go into the master cylinder don't even think about it before getting a pair of these first



There is a deep circlip that HAS to come out and without the tool to do it you are pi**ing in the wind.

[Janx101]

Slow brake squeeze vs quick brake grab... slight angle of force change on lever/pivot maybe? ..

Btw. . Xt500 pics?

[Ron888]

I agree with Sander on page two.Be sure to check the brake lever to master cylinder contact point- that can make exactly this noise!!Do that before pulling everything apart.
Hey when you mentioned your accident and losing a nail,i could feel it!!!Ouch  .I hope it feels good soon.
Btw,can you ride still?

[DevilDesire]

My finger's getting better but will take a couple of months more  The nail is no more but it will be 2-3mm shorter, I have a little part of the bone removed... Yes, I can ride but it's really cold here. It's been raining for a few days, there is now snow yet but still it's cold and wet. My genuine riding problem now is that I cannot put my gloves on I've got a little problem with the brake squeeze too but the pain is bearable.

All in all, a bad experience... At least I'll save up some money that I will later use on a new chain, sprockets, clutch lever, brake lever, front and rear brake pads, a little paint job, new handlebars, bar ends... stuff like that Maybe, if WD in the master cylinder and lever push point doesn't help, I'll get a new cylinder or a repair kit. A front new tire is also on the list.

P.S.: @Janx101: When I change the angle of force while squeezing it's OK. But I have to push down or pull up while on the squeeze to have no problem with it. If I just change the angle by a little bit it doesn't get a lot better, just a like a little relief on the lever stiffening.

By the way, all that started occuring after brake fluid change and  brake bleeding. The rear brake was done in about a minute or so and it works perfectly, the front took 10-15 minutes of bleeding and at the end of the process this started happening... I bled it a couple of times more but no change. I suspect that either I have problem with the pivot bolt or the whole lever, it may be bent a little bit. Also, Sander and Ron's suggestion sounds a lot reasonable. Bad thing is that I can't do anything now, I can't even take a philips screw off damn that right thumb....

[PantheraLeo]

Glad to hear you are improving, DD.  You'll be better in no time...in time for spring riding!

Roaring via Tapatalk.

[DevilDesire]

Today I took the brake lever off, sanded the master cylinder's piston that touch with it, I also sanded the lever and sprayed WD all over the place. Didn't do a lot tho. The cylinder's piston was rough but sanding it didn't fix the issue. The lever's touching point isn't soft either. It looks like the material's gotten mashed a bit where it pushes the piston. Is it supposed to have that little mash or it has to be smooth and roundy? After the sanding process(note that I couldn't sand the lever properly because I can't hold it still with my injured hand) it didn't get a lot better, but when I rode it, it seemed to not make much of a deal like it did before. I mean that when I squeezed the lever while riding before it was really noticable and uneven stopping to the point of almost if not actually blocking the front tire but now the bike seems to stop, say "more properly". I'll be ordering new levers anyway, hope that fixes the issue. If not I guess I'll have to rebuild the cylinder.

P.S: Is the lever supposed to have vertical free play? It goes up and down a bit. Tightening the pivot bolt took away some of the free play but not all of it. Is it supposed to be like this or is my cylinder's lever clamp area bent?

[Ron888]

Levers wear out their little bush type bearing in the pivot point.Tightening the bolt only partly fixes the problem -the looseness will soon come back. The proper fix is to fit a new lever,and possibly a new bolt.

Hmm,i'm not sure what to think of the main brake situation now.So polishing and lubing that main lever/piston contact point only partly fixed it? My feelings now are to go ahead and instal a new master cylinder.at the very least to be on the safe side.They're not very expensive.

One very important bit of knowledge i can give: Be sure to use proper brake type rubber grease when installing any master cylinder parts!Dont make the mistake i made and assume the workshop manual is always right!!The manual didnt mention anything about grease!
I went through several master cylinder kits and one genuine complete master cylinder before i found the problem.Even brand new genuine parts got sticky after a few months of use.What a nightmare 

In fact maybe you should try cleaning and greasing your master cylinder before doing anything else?It cant hurt

[DevilDesire]

I sanded the brake lever again and sprayed the hell out of it with WD-40. Much improvement has been noticed. I am ordering new levers from eBay, I didn't find any cheap ones from the shorty style that fit the GS so I'll order OEM red levers.

P.S.: What I noticed is that my lever has 6 levels of adjustment and the other GS's levers have 4. Guess my lever has been changed by the PO.

And here's some pictures of today's riding:





And here a friend of mine thought his high beams are stronger than my low beams... fool ahahahah




Merry christmas!

[Ron888]

Oops!When i said above
"My feelings now are to go ahead and instal a new master cylinder.at the very least to be on the safe side.They're not very expensive"

What i meant to say was "master cylinder KIT" ,that is, the piston part

[DevilDesire]

Well, I looked at all the kits around the ebays and I can't find one under 50$ shipped to Bulgaria.... I'll change the levers and pads now, if the problem persists, master cylinder kit it is...

[Ron888]

Wow you're in bulgaria?Cool.This forum has people from everywhere

Dont forget the rubber grease,that could be all it needs!
As i said in an earlier post- i couldn't even make genuine master cylinder or piston parts work smoothly for long without it!

To be safe,get a good brand of grease for brake rubber parts.That way you know there will be no issues with brake fluid compatibility. In australia where i am for example, PBR brand costs well under $20.
After taking the master cylinder piston out and cleaning everything, put a thin coat of the grease on the two rubber seals.That's all that's needed