Join Date: Feb 2011
Location: San Diego, CA, USA
Replace your old hydraulic lines
Hi sport touring owners. Our bikes, along with several other models, are getting fairly old now; mine is a '98 I bought new in late '97. On a ride not long ago the clutch lever pull began to to get more and more firm and over the space of several turns and four or five pulls became virtually locked up. It had operated normally prior to this (no warning signs). Fifty miles home without a clutch was an adventure (and apologies to all those drivers I pissed off while timing traffic lights along the way...!).
I figured that the problem was fairly simple (and it was) but after rebuilding the m/c it still didn't pump - or moved very slowly. The slave checked ok (and was rebuilt 2 years ago), and under no clutch spring pressure the m/c piston was able to push the slave piston out. The basket and plates, bearing and rod all checked out; no binding, warping, leaking, etc. Searching this and other forums turned up nothing that helped (adjusting the m/c piston travel for example).
I had earlier planned to replace the clutch hose anyway and had already purchased one. It turned out that the original stock hose rubber had disintegrated to the point of large chunks broken off inside the line, blocking the transmission of fluid. There was zero evidence externally that the line was cracked or broken or disintegrating. It was also not evident while bleeding - these were larger pieces that were too small to pass through the banjo hole and reveal a problem earlier during routine maintenance. New hose, another bleed, and perfect clutch operation again.
I haven't seen anything on this before so just wanted to mention my recent experience and recommend proactive hose replacement. Cheap, and easy to do. My brake hoses had long before been changed to steel braided lines, but it is a risk for anyone who still runs stock lines on the brake side too.
'98 ST2 (original owner); '11 MTS1200 Touring