Quote:
Originally Posted by javadog
Suzuki used roller bearing cranks on lots of bikes and many of those are still raced, making ridiculous power. Those cranks can work just fine…
Porsche used roller bearing cranks, back in the 1950’s….
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BMW used a roller crank on the /2 models in the 60s. When they came out with the /5 in 1969 they went to a plain bearing crank. I've rebuilt two airheads with the plain crank and they're fairly simple. Most BMW dealers can install new main bearings. If i find a /2 someday and rebuild the motor I'll have to find an old timer somewhere to send the bottom end to and have him do the work.
Roller cranks were dropped a long time ago by most manufactures, except Harley and anyone still making 2 strokes.
Some manufactures keep a feature that identifies their brand. Porsche has the rear engine flat 6, Ducati has the desmodronic valves and Harley had the 45 deg aircooled engine. Porsche dropped aircooling but kept the flat 6. Ducati dropped the desmo for their new v4 adventure bike and Harley is on its way to getting rid of the roller crank. The new Pan America is probably where Harley is going in the future.
