clicking brake lever

[Parrot of Doom]

Anyone know what could be causing this annoying noise/feel on my brake lever?

http://www.youtube.com/watch?v=cP3TkONB4js

The audio is slightly delayed.

[snotrag]

Is it an XT? Sounds like the Servo wave mechanism is a bit wobbly. Think you can see the 'knobble' in its slot on the underside.

[Trooper2]

You've got a twist in the cable, un-due the pinch bolt at the brake assembly and let it relax, readjust the brake and see if the clicking stops. The swedged lead end of the cable at the lever needs to sit perpendicular in the lever at all times whether the lever is pulled in or not. Inexpensive aftermarket cables can take a 'set' and nothing you do short of replacing the cable will help.

Kind of a hard thing to describe but if you watch your video and look at the lever end of your cable I think you'll see what I'm saying.

[snotrag]

Aint no cable there! Thats an M770 Servowave Hydrualic lever If im not mistaken, with the top cap off showing the pink mineral oil!

[Trooper2]

Look at this part of the video, not sure what this is that is twisting in the lever, to my old school eyes it looks like a swedged cable end, and you are definitely more current on bikes than I; snotrag, however being a former bicycle mechanic and a present auto mechanic, I say the clicking is coming from the red circled area in my screen capture from the O.P.'s video. Perhaps it's the end of the master cylinder's piston linkage...been awhile since I've even looked at my own bikes!....

http://i5.photobucket.com/albums/y175/dlow64/Brake...

[Parrot of Doom]

snotrag said:

Is it an XT? Sounds like the Servo wave mechanism is a bit wobbly. Think you can see the 'knobble' in its slot on the underside.

Well diagnosed. I looked on the underside of the lever, the wave mechanism ends with a circlip - that end is moving around in the slot.

I don't think it will cause any problems, but I may take it back to Merlin cycles and have it replaced, I don't think there is any adjustment, I've tried tightening the screws to no avail.

Looks like a manufacturing fault.

[snotrag]

that's the reach adjuster, it's moving normally as far as I can see. The servo wave levers are very clever in that the lever does not move the master cylinder in a linear fashion - it takes up a lot of movement in the first half, 2nd half a mucher higher leverage ratio. Thus you get lots of clearance on the pads, but they take up the' slack' quick, and then lots of power at the end of the stroke.

There's a slotted guide mechanism which does this, that's where the noise is coming from I guess.

Edit : bingo! Lucky guess...

Edited by snotrag on Thursday 26th February 02:37