Brake fluid on rear wheel

[Slaninar]

After winter, opened the garage and saw rear wheel wet from brake fluid. It has started dripping from somewhere, but very slowly. Brake fluid level is at minimum (it was almost top full), but it hasn't all leaked out.


The brake pedal is firm and feels and brakes OK. However, the fluid did leak during winter. I washed the bike and hopefully I will be able to see where the leak is from in the morning. Today I couldn't tell where it leaked from. Disc seems dry, no brake fluid on the disc, but the rear calliper is below the disc anyway.


Any tips? I'm guessing brake calliper seals are busted. Has anyone had similar problems?

[darrsi]

Obviously, as long as the bike is dry, it's easier to spot leaks at night as a torch will make the liquid shine.

[RMT1983]

if its on the wheel I would say its coming from the caliper or the pipe............... everything else would be too far forwards for it to leak on to the wheel.

Check the bleed nipples, then the banjo bolt, then the seals around the pistons.................

If its the seals then probably best bet would be to change the caliper for a 1000 blue spot. If that's the way forwards you want to go give me a shout as I have one for sale

[slappy]

Strange how it has started to leak while not in use, is the pipe still the original one? Might have become porous through age or possibly been mice nibbling it.

[Slaninar]

Strange how it has started to leak while not in use, is the pipe still the original one? Might have become porous through age or possibly been mice nibbling it.

Since yesterday 10 am, when I washed the bike, no trace of leak. It has been well over 24 hours.   


I pumped rear brake hard, to make it leak - none. All the hoses look good, no traces of leakage anywhere. But it was really dirty before yesterday - I wash it twice a year (motorcycle as well    ) - autumn and spring - just to see if anything leaks. Now after washing, I'll spot any traces of fluid leaking easily.


Is it possible that during winter, no use, low temp, something shrunk a bit, but after it has been used, the seal (fluid + rubber) started working again?  Will check it tonight, under flash light as Darrsi advised and see if anything shows. In autumn, after the riding season I plan to change rubber seals just in case. Non OEM ones can be sourced locally for around 10 euros - to little to worry about it.

[fazersharp]

Really - not trying to be funny here, but are you sure that a dog has not just "cocked its leg" up at your back wheel as when it dry s it would leave a mark like an oil leak.

[Slaninar]

Really - not trying to be funny here, but are you sure that a dog has not just "cocked its leg" up at your back wheel as when it dry s it would leave a mark like an oil leak.

    Good idea and yes, I've considered that as well. 


Dogs don't enter the garage, but who knows. I'll see if it starts leaking again. I'll also mark the oil level in the container.