Bike MC Problem
scootz - 18/3/14 at 05:23 PM
Evenin all.
I've been getting my bike ready for going back on the road and noticed there were a dozen or so black flakes inside the front brakes MC reservoir
which have undoubtedly come from the corroding plastic cap.
I'm thinking it's highly likely that some of these (who knows how many!) will have made their way into the MC itself. 
Unfortunately, there's no rebuild kit for this type of MC, so it will be a quite a costly excersise in swapping over to a new one.
Am I overreacting (can you overreact when it comes to brake operation?)? Or should I just fork out and but a new one?
Ben_Copeland - 18/3/14 at 05:40 PM
Why not just clean it out if your worried about it?
chrism - 18/3/14 at 05:49 PM
One thing to try is a tip I read recently to help bleed tricky bike clutch's.
Get a syringe and piece of tube attached to it and fill with brake fluid then make sure all the air is out of it.
Empty most of the fluid out of the reservior
Attach the tube to the bleed nipple on one of the calipers and squeeze the syringe.
The Fluid will push through the system in reverse so if anythings gone into the master cylinder bits will come out back into the reservoir and you
will be able to see if you need to delve deeper with it.
Matt21 - 18/3/14 at 06:01 PM
I would....
remove the mc, pour it out and give it a good clean
attach an easy bleed pipe to the bleed nipple of the caliper and blow fresh fluid through the caliper and hose and out the top.
pop the mc back on and bleed as normal
sorted
though the plastic bits are most likely just sat on top of the fluid and aren't in anything important. but for the sake of £6 for some fluid, you
might as well blow it all through
scootz - 18/3/14 at 06:17 PM
quote:
Originally posted by Matt21
I would....
remove the mc, pour it out and give it a good clean
attach an easy bleed pipe to the bleed nipple of the caliper and blow fresh fluid through the caliper and hose and out the top.
pop the mc back on and bleed as normal
sorted
though the plastic bits are most likely just sat on top of the fluid and aren't in anything important. but for the sake of £6 for some fluid, you
might as well blow it all through
Cheers, I will be flushing the system through, but I'm concerned that the flakes that have entered the MC will have been trapped around the
piston and may cause a braking problem in the future.
scootz - 18/3/14 at 06:19 PM
quote:
Originally posted by Ben_Copeland
Why not just clean it out if your worried about it?
The MC or reservoir?
I can't clean out the MC as the piston seal will need replaced if I go in there, and there are no rebuild kits for it...
The reservoir will be getting emptied and the system flushed.
See previous message for my main concern.
scootz - 18/3/14 at 06:20 PM
quote:
Originally posted by chrism
One thing to try is a tip I read recently to help bleed tricky bike clutch's.
Get a syringe and piece of tube attached to it and fill with brake fluid then make sure all the air is out of it.
Empty most of the fluid out of the reservior
Attach the tube to the bleed nipple on one of the calipers and squeeze the syringe.
The Fluid will push through the system in reverse so if anythings gone into the master cylinder bits will come out back into the reservoir and you
will be able to see if you need to delve deeper with it.
Cheers! Worth a pop!