Vibration

76 KZ750 Twin
2 in to 1, Pods, cafe seat, drag bars, relocated electrical, mounting tabs cut off, fenders and instrument cluster removed, and the rear frame removed just behind the shocks.

When I got it I reset the points, bled the brakes, reset the idle and primary mixture, and did some body work.

There is a pretty annoying vibration transmitting through the handlebars. I didn't ride the bike more then a few blocks before I started hacking and grinding and changing parts, so I am not sure if the problem is something I did or if it was a preexisting condition.

I cant seem to find the torque specs for the engine to frame mounts in my service manual or on google, so I tightened them to the point my 3/8 cordless Makita impact stopped turning them. I also checked the rubber bushings around the bars on the triple tree, and it all looks good.

Any ideas what else could be causing this? I dont want to just cover it up by using weighted bar ends and foam grips, but it makes highway riding miserable.

xbmxxx wrote: 76 KZ750 Twin


Any ideas what else could be causing this?

Hard to say, maybe it's normal twin vibration.

Got the carbs supported in back?

Checked valve clearances?

Did you rejet the carbs for the pod filters and exhaust? And did you sync the carbs after jetting?

Its probably just the typical parallel twin vibe you get from those engines. My XS650 did the same thing. Some things you have to get dead on are the timing and carb syncing or else each cylinder is going to fight each other. I changed my sprockets too so that it wouldnt buzz so much at 65 mph.