I'll probably forget something and I have only owned my RE G5 for about 2 1/2 months but here is a listing of the problems I've had/read about on the UCE bikes (mostly American imports).
The problems are listed as I think of them .
Burned out light bulbs. (Easily replaced)
Shorts in the wiring system. (Poor protective insulation consisting of a great use of plastic electrical tape combined with sharp metal edges. Much of this can be avoided by using slit rubber/plastic tubing to cover the wires in the vicinity of sharp metal edges)
One defective alternator.
Several electrical start sprag clutch failures.
Several cases of loud unexplained ticking/knocking noises.
Instability at high speeds. (often fixed by lowering tire pressures. Some people suggest replacing the white swing arm spacers with the newer black ones. Also, loosening the front suspension bolts, bouncing the front tire on the ground and retightening the bolts.)
Electric Starter solinoid failure. (The best fix seems to be replacing it with a non RE part).
Loosening of fasteners. (Check often and use the Blue Loc-Tite thread locking adhesive to secure)
Chain and rear sprocket wear. (Lube often, adjust to factory specs (1" loose) as required.)
Difficulty replacing oil filler cap. (Install redesigned cap assy. or add a screw to hold the filter retainer/filter bypass valve disk in place.)
False neutrals in shifting transmission. (usually get better with using fully synthetic oil and additional break in milage).
Computer does not boot up when trying to start. (Check sidestand switch. Disconnect if defective).
Engine searching for correct idle speed. (Replace Bosch spark plug with NGK BPR6ES and reduce idle speed slightly by turning the brass screw in the top of the throttle body clockwise about 1/8 turn).
I'm sure there are more but for now these are ones that stuck in my mind.
As you can see, the new EFI, UCE powered bikes are prooving to be pretty "Bullet proof". (small pun there.
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