23 April 2015

Brandon gets his bike back + and tips on installing Denso brushes

I think the gods were against this Ducati ever getting back to the owner. After fixing the original issues (electrical problems, new ignition and tank lock, and fork brace) that the bike arrived with, then replacing completely worn out rear brake pads, I called Brandon and let him know his bike was finished and that he should come over and warm it up so I could change the oil + filter, then send him on his way. He didn't think something felt quite right during the test run so I figured I'd take a ride to see what was up (it wound up just being an under-inflated rear tire). About two blocks away the clutch lever broke off in my hands...

There were signs that this bike had been crashed by the PO, and likely why the bike was turned into a naked rat, and the clutch lever must have been damaged and just needed enough pulls to snap. No big deal, $34 got a nice condition complete lever and clutch master cylinder. Put that on, bled the system, reset the choke, and called Brandon back to tell him his bike was done, again. He comes over and I go to start the bike, crank, crank, dead. The starter motor just stopped. Diagnosing the issue ruled out the solenoid and indicated starter problems. Bad, bad bad... Removal of the starter motor requires draining the oil, removing the shifter, the complete left side case, the alternator, and then accessing the hidden mounting bolts. That being said, access to the brushes can be done by removing the oil cooler hoses on the right side of the bike, then the two long bolts on the right side of the starter. Figuring I'd check the easy stuff before completely removing the starter, that's what I did first. I was expecting somewhat worn brushes, but not this...

What you're looking at is a positive brush that broke apart, followed by the two armature shims that somehow welded to each other, broke off, and then re-welded themselves to the brush spring. I'm speechless. $10 later, a shop put on brand new brushes and returned the brush plate, now time to mount it.

From this angle the install looks really easy and straightforward. What can't really be discerned in the photo is that the oil cooler inlets protrude from the case enough to make it impossible to put the cap back on by going straight in, you have to cock it and fit it. I first attempted to put the cap and brush plate on as a unit (with the slots already aligned), this made the most sense to me at the time, but was a total failure. Way too difficult to get the brushes on the armature along with the cap mounted correctly to the starter. Next I removed the brush plate from the cap (which meant removing the bolts from the cap that connects to the brush and the positive electrical lead). That made it easy to get the plate on, and the cap on, but next to impossible to get the bolt back into the cap and get the cap back on. Finally, an hour and a half later, I came to the conclusion that I'd leave the bolt in the cap, but leave the nut on at the very last thread of the bolt. This would leave me enough slack to get the brush plate on the armature, and wiggle the cap on, and then pull the bolt fully through the cap and tighten up the retaining nut. Voila...

Buttoned everything up, started it up, starter whirred like a jet engine, and everything is good again. I couldn't be happier to return the bike to the owner.

And here's the happy couple. 

It's rewarding to bring life back to a motor that hasn't run in years, restore the driveability and integrity of the bike, and see the owner beaming to go on his first ride in about 3 years.

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