03-14-2014, 07:02 PM
I was cruising down the freeway last Sunday when I noticed I hadn't bothered to shift into 5th (as usual). I was turning 5K rpm in 4th and that feels normal to me, since that's what the CB750 does in 5th at 75 mph. When I shifted into 5th and the rpm dropped to 4200, I noticed that I actually felt more vibes in the bars than I had at 5K. I thought it was a bit strange, so I shifted back and forth and it definitely seemed shakier at the lower rpm. Maybe that's why my brain so often forgets to shift up from 4th gear.
I used to own a lot of twins with 360 cranks, so vibration was just a normal part of motorcycling. When I took my first ride on an I-4 bike ( a Kaw Z-1) I was stunned. I never knew a motorcycle could be so smooth. In fact after I started it, I had to double check the tach to verify that the engine was running. I don't think I'll ever go back.
BTW, the shakiest bike I've ever ridden was a Yammie XS650 twin that was converted to a "twingle". The cam was modified so that both cylinders would fire simultaneously. Interesting bike, but it couldn't be kick started by anyone under 250 lbs. and the electric start would only work if you hooked a car battery to it. The guy that modified it didn't think of adding a compression release
I used to own a lot of twins with 360 cranks, so vibration was just a normal part of motorcycling. When I took my first ride on an I-4 bike ( a Kaw Z-1) I was stunned. I never knew a motorcycle could be so smooth. In fact after I started it, I had to double check the tach to verify that the engine was running. I don't think I'll ever go back.
BTW, the shakiest bike I've ever ridden was a Yammie XS650 twin that was converted to a "twingle". The cam was modified so that both cylinders would fire simultaneously. Interesting bike, but it couldn't be kick started by anyone under 250 lbs. and the electric start would only work if you hooked a car battery to it. The guy that modified it didn't think of adding a compression release