sticky front brake

[mattster31]

I've been experiencing a sticky front brake over the last few weeks. I thought it was just the lever so I greased it and made sure the bolt was not over tight......yet no change. My next thought is the master cylinder. It feels like stiction I've never had this happen but anything is possible guess. Thoughts? Thanks in advance.

 

[FJRay]

When my 03 had a similar issue it was the pistons in the caliper sticking. Took it all apart and did a good cleaning and life is good. Make sure you take everything out and clean it good. spraying the outside with brake clean doesn't work.

 

[wfooshee]

+1. Pistons aren't retracting. I just went through and replaced all the caliper seals, four kits in all. There's a kit for the small pistons of one caliper, and a kit for the large pistons of one caliper. You need two of each kit.

Pulling the pistons and cleaning them wasn't enough for me, I still had dragging front brakes, enough so that the pads were gone in less than 20,000 miles.

 

[mattster31]

Thanks for the advice guys but I don't think I was clear enough. The stiction I feel is when I am applying the brakes at the lever. The calipers themselves are releasing just fine. If I could compare it to a front fork that is sticking during compression. I think its sticking in the master cylinder.

 

[wfooshee]

So the lever moves, catches, moves, catches, right? You have not quite enough brake, squeeze a little harder, and it releases into too much brake. BTDT got the t-shirt.

Still the seals, same cause. Non-smooth motion, piston grunge catching on the seals. Pulling them and giving them a thorough cleaning to restore shiny-smooth piston walls will help, but those seals have been chewed and will need to come out. May as well do it while you're in there. Take it from one who's been in there twice now because he tried to skip that step and hope for the best.

It's at the bottom end of the brake system, not the top.

 

[mattster31]

So the lever moves, catches, moves, catches, right? You have not quite enough brake, squeeze a little harder, and it releases into too much brake. BTDT got the t-shirt.

Still the seals, same cause. Non-smooth motion, piston grunge catching on the seals. Pulling them and giving them a thorough cleaning to restore shiny-smooth piston walls will help, but those seals have been chewed and will need to come out. May as well do it while you're in there. Take it from one who's been in there twice now because he tried to skip that step and hope for the best.

It's at the bottom end of the brake system, not the top.

Thanks for the advice......guess I'm going to have to suck it up and tear it all apart :-( the season will be winding down in a month or so. I may try and hold off and make it a winter project ........

 

[garyahouse]

I've been experiencing a sticky front brake over the last few weeks. I thought it was just the lever so I greased it and made sure the bolt was not over tight......yet no change. My next thought is the master cylinder. It feels like stiction I've never had this happen but anything is possible guess. Thoughts? Thanks in advance.

Motorcycle brakes, by design, need a lot more TLC than most of us give them. Not sure this applies in your particular case, but in the future, it'd be a good idea to flush out that fluid every so often (ask the pros on this site for advice on frequency) just to keep things a little cleaner. It's amazing how grungy the inside of the calipers can get when not properly maintaned. I've also had sticky brakes with other bikes because of air in the lines, though I thought I did a good job bleeding them. The dealer fixed the problem. You describe a sticky master cylinder or lever it seems. Never heard of that one, but I'm sure it can happen. Good luck.

 

[madmike2]

I flush my brake system every Winter/Spring, just before the heavy rideing season. I have used a Q-tip to get the splooge from the bottom of the master cylinder. Brake fluid, being agroscopic, tends to turn "funny" when it collects enough moisture.