Rebuild Complete

AJ’s motorcycles finally finished the rebuild of my Burgie’s engine after I suffered from a cracked and bent drive shaft I wrote about before.  They finished back in July and I was on the road that next month and riding to work.

Having purchased the scooter with 24,000 miles on it I was unaware of what a new Burgman scooter was like.  Having had almost daily conversations and updates about the scooter’s engine during the time it was being rebuilt I learned that the engine, while I thought was in fantastic shape, was in fact in a precarious situation.  The engine produced plenty of power however I did notice before the mishap that led to my repairs that the engine was beginning to emit a whine that was becoming increasingly louder over time.  As it turned out, two of the main bearings at each end of the flywheel had signs of being spun in their housings.  Additionally, I handled said bearings and was immediately shocked at how rough they were to spin in their races.  I immediately decided to have all bearings replaced.

As I mentioned in the Long Weekend post, the engine sounded great when I first started it up.  Sadly as I also indicated, I was unable to get the scooter to move.  The problem it turns out was that the primary pulley wasn’t set properly into a position that the computer could understand and so it tried putting the pulley into a position that bound the motor which resulted in a near failure of the rectifier due to an over-current condition.  Near meaning that at slow RPM it worked as expected however at higher RPM’s the rectifier couldn’t produce enough current causing the voltage to drop at the battery.

Before I realized the damage to the rectifier I was able to get the primary pulley, with the advise of the mechanic, Larry, of AJ’s motorcycles, into a position that the computer could work with by removing the pulley position sensor and manually turning the pulley to a mid position.  This meant that I had to get the back tire off the ground by putting the bike on the center stand and starting up the engine with the pulley motor unplugged.  Once I had done this I plugged in the motor, started the engine, and noticed as I watched through the hole the sensor occupies that that computer tried to position the pulley into a position that was once again wrong.  Having observed this I unplugged the motor, put the pulley into what I thought was center of it’s range.  With the scooter shut down I plugged in the pulley motor and remounted the position sensor.  I started up the bike and it came to life.  I was on the road again.

So what was it like?  As I mentioned before when I learned the scooter wouldn’t move, the engine sounded great.  It has the sound a high performance motor is expected to have and knowing the heritage this scooter motor comes from I shouldn’t be surprised, yet was.  Solid pops from each cylinder as they fired; instantaneous throttle response; split second from idle to 8000 RPM.  For a scooter, amazing.  The first thing I noticed when then CVT was alive and working was how much more quiet the whole scooter was.  The bearings were in fact worn significantly with the reason forever lost.  The sound I was hearing before the failure, and getting worse, had to have been the bearings failing.  Did the machine get run dry of oil by accident?  Bad Oil?  What causes such large bearings to begin to fail uniformly throughout the engine?

Not only did the scooter sound better and much quieter, it accelerated much more smoothly and consistently than before.  Gone was the slight hesitation just as the throttle was applied.  Gone was the flat spot in the RPM range between 2000 and 3000 RPM.  Those problems were replaced with the sounds of the wind in the helmet and the whine of the final drive, a sound I find pleasant to my ear.

Acceleration wasn’t much improved, but was noticeably smoother.  Vibration was significantly reduced in the feet, seat, and handlebar.  I already loved this scooter and here I was falling in love again.

Sadly however earlier this year I wrecked another scooter of mine.  A 2006 Honda Helix.  A cult classic of a scooter.  The damages to my body and the subsequent care required me to sell my Burgman to cover the balance of the hospital costs.  I still have what remains of the Helix, however I don’t believe I have it within my desire to get it repaired.  Time will tell.