Consumers Reports in the motorcycle reliability study referred to by someone above goes into a lot of detail about what the definition of a "major" repair in the first four years of ownership means. It also breaks the problems down into ten categories (repaired parts) and what % of the repairs went to each category. Electrical was number one at 24% of the problems and these were major problems like a stator failure.
Cost of the same repairs also varied greatly among manufacturers with Kawasaki at the bottom (least expensive for a repair on average) and BMW at the top of the cost range for the same repair (although they noted that many people save money by fixing their own bikes and parts only represented the difference).
12,300 motorcycles were used in their study. Consumer Reports needs to update the study which is a couple of years old. Consumer Reports sought feedback from the various manufacturers on the study to improve it and most had no comment but a few were very supportive even though their bikes were not in the highly reliable Japanese class.
The word is CR is updating it so hang on... we shall see if certain brands are improving (as some claim) or actually did even worse which others are suggesting.
Consumer Reports will continue controversial motorcycle ratings
"There is a four times greater chance that a BMW will need repair than a Yamaha," said Consumer Reports' deputy editor Jeff Bartlett. "That's pretty significant, when you consider the cost of servicing a BMW is substantially higher. BMW makes great bikes, but the BMW owner has to have a few dollars set aside for repairs."
The owners of some brands don't care if the reliability stinks.
Interesting the Polaris killed off the motorcycle line (low sales) that was pretty reliable and had the highest owner satisfaction to pursue Indian. Honda was next after Polaris/Victory and then Harley in owner satisfaction of any brand. Even more shocking but maybe not surprising was they the surveys indicated that paying more for purchase and maintenance may actually support brand image.
"Curiously, despite these statistical results, the most reliable motorcycles were not the best loved by their owners. Harley-Davidson owners rated their machines second-highest, after the smaller Victory brand, among those who were asked whether they would buy the same motorcycle again."