stiff throttle return spring

The throttle return spring on my Z1-B is too strong. Does anyone else feel this way? I can twist the throttle but it is really over-kill on the resistance. The linkage is smooth. It is just the spring force. Is there a way to heat treat the spring to weaken it a little? Or perhaps a new spring?

I have ridden my brother's '77 KZ1000 LTD and his throttle pull back is way lighter than mine. His carburetors have a different spring set-up. His spring is pulled. My spring is twisted. I am thinking that's the difference. Any ideas?

I know this sounds obvious, but have you taken both pull and return cables and adjusted them in both directions? I had the same thing on my z1b, but it was just too much tension on the return cable at the linkage AND at the throttle grip. Can't hurt to check!

Had the same symptom when I first got my KZ650-B1.

I went to my automotive store and bought a similar enough spring with much less pull.

I would never go back to the original.

I even added one of these crouse-control throttle-lock accessories for highway driving... with zero tension. Much more relaxing IMHO.

Best of success.
Bill

Try and removing the returm cable. I just run one cable on my bikes. Roy

Am thinking the spring at hand is the earlier carb spring, which is not so easily replaced at the hardware store like the later KZ900 spring.



Don't know if still available, but once upon a time there was an aftermarket accessory adjustable counterspring that fit inside the handlebar connected to the throttle grip. Its purpose was to offset the carb spring with a twisting force toward "opening" the throttle grip. I had one and remember that it worked pretty well. Haven't seen one in a long time, but doesn't mean they aren't still around.

Good Luck!

J, After eliminating cable/carb stiffness, you might give Sudco a call. I seem to recall an optional "lighter' return spring avail. for VM's.at @ 6-7 bucks a pop. Bear in mind, at full throttle in some cases there existed the possibility on some models for enough vaccumn to keep slides from closing w/out assist.(thus heavy return spring) do as you will, But I would retain "close" cable as insurance.(also in a press, it can be re-installed to A cable mount to get one home abett working backwards) Note, this only applies to VM carbs w/ external "free standing" springs, luck G