Premature rear brake wear

[RichMaund]

Folks

I have read a number of letters in different places about premature rear brake wear on the V11S type bikes. Mine has always had a slight "wup......wup" sound at slow parking lot speeds. But the rotor wasn't warped and the brake functioned well enough. Not strong. But OK. No signs of overheating and melting anything either. So I never gave it any more thought.

Last week with 8K miles on the bike I tore into it for some preventive maintenance. I flushed all the hydraulic systems and tore down the rear drive to grease everything. Actually a much easier job here than on a Tonti framed bike. :-)

I found one rear wheel bearing felt notchy. That was depressing, but I was happy to have found it before it completely failed. The local bearing shop sold me two bearings the next morning for under $17 to replace them. Smooth as silk now. The real surprise was finding the rear brake pads worn to under 1/16" thickness!

Here's how I believe the problem came about.

The rear caliper mounts upside down. So the vent for it is on the bottom. Air bubbles float up right? When I bled it, I did so by removing it and placing it upright to get a good bleed on it. I did find some air trapped in it. Any chance the factory bled the system with the caliper installed so that the vent was on the bottom when they vented it? I think so. Sheesh! If air was trapped in the caliper, it would be warmed by the hot brake pads/pucks and expand as I rode the bike, thus making the brake drag a bit. Remember I mentioned mine made a "whup whup" sound at low speeds? Apparently it was dragging a bit ALL the time. I just couldn't hear or feel it.

I did check to see that the pucks moved inward smoothly as I pumped up the rear brake. No problems there. No binding. After reassembly the unit worked very smoothly. NO dragging and no more noises. May be my imagination, but the rear brake has better feel and power to it as well. 100 miles later now and it continues to work quietly. No more dragging noises. I believe the air in the caliper was the problem.

 

It's very simple to remove, flip right side up and bleed the rear brakes on these bikes. I recommend you try that if you have noises similar to what I have experienced. It could get really expensive if you wear the brakes down to bare metal.

 

Joe Eish got me a new set of rear brake pads in today. (God bless Joe!) I'll install those tomorrow before we ride up for the MD Rally in Hagerstown this weekend. Hope to see some of you there!

[al_roethlisberger]

Rich,

 

I saw the various replies to your question on the MGCL list, where several folks felt that it was more of an issue where the vent was clogging.... if you have any updates on this condition, that would be very helpful.

 

But on another, but similar, note.... has anyone had the gold anodization on their rear disc start to discolor(darken) about 1/4 inch wide along the edge where the gold stops and the real disc material is?

 

My rear drags a bit sometimes too... the infamous "groan", but a quick tap on the brake cures it. I'm just wondering if my disc has been overheated once or twice, and the anodization got a bit "burned". ...wonder if this would be a warantte issue?

 

Anyone else have this happen? It just looks a bit funky, and I'm mildy concerned that the gold will start to come off.

 

BTW, the disc still seems true, and the brake functions fine. It's just aesthetic at this point.

 

al

[RichMaund]

Al and all

I replaced my badly worn rear brake shoes a hundred miles after I did the service to the hydraulics. During that 100 miles the rear brake never dragged again. Now I have gone almost 900 miles on the new rear brake shoes. At first, they dragged a little. Tapping the rear brake pedal solved it. I took the caliper off at the campground and cycled the pucks in and back a few times and put it back on. (I did lube the pins when I replaced the pads.) Problem solved. It hasn't dragged since then. I don't fully understand why it helped, but it did. Works beautifully now.

I completed my 9000 mile servicing today. Both intakes were .001" loose and the exhausts were spot on since the last check. I checked the balance with a Twin Max and it was still perfect. The bike runs like a dream!

Just to make myself feel better, I re-polished my valve covers and buffed up the alloy cans on the pipes while I was at it. Now she shines!

(I rode through so much torrential rain in the last year that the paint started flaking off the fronts of my valve covers. Not covered under warranty. So I bead blasted the paint off and machine buffed them. They look really sweet and aren't too much trouble to keep up!)

[Mike Stewart]

I just finished putting my wheels back on my 2000 V11Sport (fitted new Bridgestone 010s), when I noticed the rear brake pads are almost to metal. This is the first bike I have ever worn out a set of pads. I am off to the Guzzi's by the sea rally this weekend and need to find a set by Friday. I did some research and to my luck Ducati uses the same pad. Well, I have learned to check the rear brakes more often. I guess 13,000 miles for a set of pads isn't that bad.

 

Mike Stewart

[callison]

Hey Mike. I'll see you at the shindig this weekend. I don't know if my ISP is blocking your email to me, but I'm having real problems getting mail these days, so if you could send me a message at guzzi007@postoffice.pacbell.net and/or guzzi007@pacbell.net I would appreciate it. Also, are you going to the SoCal rally in two weeks? I want to hook up with someone to ride down with.

[emry]

I found that removing the pad tension spring, (the small spring with two pins attached that rides under the retaining pin,) solved almost all of the noise. The springs pins are tapered on my scura and were causing the pads to pinch the rotor at the base of the pad.

[RichMaund]

Emry

You may want to consider putting that spring back in. It provides much friction to retain the main pin. If that main pin comes out, your pucks will bail out on you!

I found that gently brass bristle brushing mine and greasing the pins helped as did cycling the pucks back & forth after assembly.

That spring & pin assembly is there for a purpose. Please consider putting it back in.

[dlaing]

I'll second Rich's motion to put the spring back in.

Emry, perhaps you could level out the taper on the springs with a file, or, file the contact point on the pads to better mate with the spring.

I was having sounds come out of the rear brakes for a while, it took two lubings by the dealer to get the sound to go away. He used chain lube or chain wax.

The dealer also lubed the front disk floater, which took away some pulsation that I thought was warped routers. That lasted a little while, and then I had to lube it again. Also, A little brake cleaner to clean the disks after lubing is not a bad idea.

[emry]

I drilled a small hole on the tapered end of the retaining pin so that a small R-clip could be used. Between that and the tension of the internal locking clip the pin it will not go anywhere. Thanks for your concern.