Design Disadvantages of the CB1100

[treytexag_imp]

thessler, good write up here. I learned alot in your short paragraph - thanks for sharing it my man.

Trey

I see a lot of mis-truths posted in this article about inline 4 cylinder vibration. Inline fours with 180 degree cranks have very good primary balance and very poor secondary balance. Primary vibration is at crankshaft RPM. Secondary is at twice engine RPM. Most inline fours have balance shafts. The CB1100 and ZX-9 and most other fours have a single balance shaft that turns at twice engine RPM. Some bikes, like the Blackbird have two shafts that turn in opposite directions. In either case, the shafts help, but rotating weights are a compromise when trying to cancel reciprocating motion. Balance shafts were first invented and patented by British engineer Frederick W. Lanchester in 1904. Most 4 cylinder cars have balancer shafts and rubber mounts. Think of it as belt and suspenders. CB1100 does have one rubber mount at rear. Nearly every engine configuration on motorcycles has inherent vibration of some sort. Exceptions are the sixes - CBX and Gold Wing are quite smooth and need no balancer shafts. 90 degree V-twins are smooth in moderate displacements, but have some secondary vibrations. I have a classic Ducati 750GT that is pretty smooth. I am sensitive to vibration in my hands after riding for more than 50 years and I have studied the subject extensively.