tach slips at 6 grand?

hey, anybody my tach slips when it gets to 6,ooo.
I took the tach off and put it on my brothers z-1 classic and it worked fine! My cable and tach drive seem fine, does anyone know what might be the problem?
thanks

try putting your cable on your brothers bike and see if it works,if it fine check the gears on tach drive!goodluck,happy wrenching!

What do you mean by "slips"? Do you mean that it won't read past six grand or that once it gets to six grand it goes way higher?

KZCSI

I had the same problem with mine. It's not the tach it is the vibration of the bike. I fixed mine by replacing the foam under the tach.

around 6 grand the needle seems to stick or slip, until I keep acclerating, and then the needle will jump to 7500 - 8000.
I'll try putting my cable and tach on my bros bike, and if it still works(wireman), I guess Ill wait until I get my bike back together to add some foam underneath ( when I took the tach off my bike, the orginal foam was almost gone!, your probably right, baldy ).
THANKS to everyone who replyed to my ?.
All by the way, starting rebuild project, already painted engine high temp satin black, just got the frame back from LINE-X, and Im sending my swingarm, fork covers, calipers, and all engine covers to get a powder coat.
ride safe, piece

I would say vibration. Had trouble with dragbike and tach was jumping all over the place after 6000rpm. Not that I paid it much mind after launching anyway. Make sure it is bolted tight, foam is good and bracket is tight to triple clamp.