Join Date: Apr 2005
Location: Guilford, CT, USA
There are several possibilities. Since it is directly under the centerstand, that appears to be most likely. I think a leaking rear master cylinder, leaking brake reservoir, or leaking rear brake line would be off to the right. Ditto tranny output shaft seal. Rear brakes should feel mushy and in need of bleeding if the brake circuit is leaking, and I think the ABS computer would pick up lowered volume in the reservoir. The slave cylinder is midline, but forward of the center stand. However, you might have DOT 4 from the slave cylinder leaking down and then running back toward the location of the center stand before it drips to the floor. Clutch action would feel mushy, however, if air is getting into the circuit from a loose banjo bolt. Rear shock pre-load adjustment mechanism is remotely possible, I guess. And don't quite discount the dealer's suggestion; I think he means that when there was an oil change there was a spill of the new engine oil, which can collect down in the bottom fairing and then blow back at speed. It would look fresh 'cause it has never been in the engine. However, if that were the case I would have thought he would LOOK for the evidence, not just speculate.
I'd suggest you get a 2 x 2 foot square of white cardboard. Cut it in half, and then cut out openings in each half to fit around the feet of the center stand. After parking the bike on the center stand, put the two halves on the ground, fitting them around the feet of the centerstand. Do this every day for a month or so. The cardboard will remain in a constant position relative to the bike, even if you don't park the bike in exactly the same place every day. When you notice a drip on the cardboard, mark it with a date. See if the drips are in the same place or if they are scattered around. Try to find the place on the underside of the bike that is vertically above the drip. With a good light you should be able to see if there is an oil path that leads away from that point or if the oil originates at that point. Do the sniff test to see if you can tell whether the drip on the cardboard is engine oil, gear oil, or brake fluid. This might immediately eliminate some possibilities. Once you have eliminated possibilities (particularly the dealer's speculation), or determined where the drip originates, take it back to the dealer for a fix (unless you do this work yourself). Good luck.
'99 Canyon Red K1200 LT - Buddah Bike