brake fluid only/mainly goes to the right side...

[andylawcc]

i was taking off my calipers, and i notice the brake wear is significantly higher on the pads on the right side than the left. I suspect a stuck piston on the left side, so i took both caliper out. After I took them out, i press the brake lever to push the extra fluid left in the hose, and i notice only the right side banjo bolt (unison bolt?) squirts fluid, and the left one only drips. After completely draining the brake fluid, i spray from brake cleaner in the reservoir (not sure if i should have done that, will it mess up the MC piston seals?), and press the lever again, brake fluid once again squirt out on the right side, and mildly drips on the left.

so, i suspect something is clogged up at the point where the left and right hose+unison bolt meets at the lower triple tree.
Or, this is purely by design: as the hose+unison bolt to the right caliper is placed under the one to the left, and pressure is simply stronger on the bottom one. It is similar to theory like this:

http://thehappyscientist.com/science-experiment/three-holes

so, am i thinking too much?

[jayel]

so, am i thinking too much?

Yes, either the bolt or the left side hose is plugged, the holes in the bottle don't have to push anything, say like brake pads against a disc? how old are your hoses quite possible they may be breaking down inside, dis-assemble and clean everything

[natemoen]

It is also possible that the internal lining of the brake lines are collapsing and restricting flow.

[BA80]

Most likely the hose is plugged either with junk or as Nate said a deteriorated lining. Try taking them off and flushing them with brake cleaner and air pressure. Replacing them would be best.

The brake cleaner shouldn't hurt the master, it's designed to clean brake parts without damaging them.

[DGXSER]

For the science geek in me, there is a difference between gravitational pressure and induced pressure. In the two litre bottle. only the pressure on the quantity of water above is pushing the water out the three holes, so there will be a difference in the amount of water that comes from each. If you took the same two litre and put the lid in it and now used say compressed air or similar to push the water out, the streams would equalize.

Your brake system is under induced pressure from the master cylinder, so pressure would be equal throughout. In your case, you have a restriction in the left side line, so more pressure is required to push the same amount of fluid into that caliper.

Short answer, yes, you need to clean and or replace the brake lines.

[andylawcc]

For the science geek in me, there is a difference between gravitational pressure and induced pressure. In the two litre bottle. only the pressure on the quantity of water above is pushing the water out the three holes, so there will be a difference in the amount of water that comes from each. If you took the same two litre and put the lid in it and now used say compressed air or similar to push the water out, the streams would equalize.

Your brake system is under induced pressure from the master cylinder, so pressure would be equal throughout. In your case, you have a restriction in the left side line, so more pressure is required to push the same amount of fluid into that caliper.

Short answer, yes, you need to clean and or replace the brake lines.

:thumbup;

and thanks guys

[fredintoon]

i was taking off my calipers, and i notice the brake wear is significantly higher on the pads on the right side than the left. - - -

Hi Andy,
you don't say if your bike is a Standard or a Special.
If it's a Standard, yes, the visual evidence is that one set of pads is wearing faster than the other.
If it's a Special, it has those Weird Harold swivelling brake calipers that use tapered pads and that may be confusing the issue.
Either way, clean out the entire brake system and change the stock fabric braided brake lines for stainless steel wire braided brake lines.
It's not cheap to do but it's well worth it, the brake upgrade is like night and day.