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Clutch Or Brake Plugged Return Port

Clutch Symptoms

Clutch works fine at first, but after riding for some time, begins to slip.

Brake Symptoms

Brake works fine at first, but after riding for some time, the brakes won't release after being applied or will apply all by themselves.

Clutch Diagnosis

Pump clutch lever repeatedly to see if slippage can be induced. If so, the return port in the clutch master cylinder is probably plugged.

Brake Diagnosis

Ride and brake repeatedly to see if the brakes won't release. If they won't, then the return port in the clutch master cylinder is probably plugged (alternative culprit is stuck caliper pin).

Confirm Diagnosis

The easiest way to know for sure is to open the lid on the reservoir, remove the splash guard over the return port, squeeze the clutch lever and then GENTLY release the clutch lever. If you see a squirt forming in the reservoir as you start to release the clutch, your return port is fine and you should look elsewhere. If you don't see any action in the reservoir, try releasing the clutch lever with normal action. If fluid does not fly skyward (protect your paint first), the return port is plugged.

Quick and Dirty Fix

Crack the bleeder valve on the offending slave cylinder/caliper(s) to relieve the pressure to get you home.

Correct Fix

Unplug the port. Can't find it? Cliff Koch writes:

clutchmaster.jpg

If you have a problem finding something small enough to clean out the return port, get yourself over to Wally World and head for the sewing section. After going through my small stuff, down to the #80 drill at 0.0135 inch I found that the smallest needle in the Singer brand assortment of 45 "hand needles" worked fine. Cost all of $1.25 so it is a Maggot priced tool too. UPC 75691 30020 Jim Mc Adams