Signal flashes faster on right side than on left,

All my signals work correctly ('75 KZ400), but the right side flashes twice as fast as the left side. Usually this means that a bulb is out, but all of them work. The flasher is a standard thermal flasher, probably the original.

Another issue is that the "stop lamp" indicator is always on, even though the brake light works normally on front and rear brakes. Could these two problems be related?

For the flashing question; I would swap the 2 left bulbs with the 2 right bulbs and see if the problem moves with the bulbs. If so, just put in 4 new bulbs, if not it may be in the Left/Right handlebar switch or wiring. I wouldn't expect it to be the flasher unit. Ed

Have you replaced any bulbs lately?
It has been reported that new bulbs don't work right w the old flahser. One fix is to get a heavy duty trailer flasher from the auto parts store.

Make sure the bulbs are the correct wattage or they will flash at the wrong rate. I think these bikes use the 1157 type bulbs.

Can't be the flasher because it is common to both circuit branches, left and right, but selected by the TS switch.

Audinos wrote:

Another issue is that the "stop lamp" indicator is always on, even though the brake light works normally on front and rear brakes. Could these two problems be related?

Make sure you have the correct bulb in there. All of your problems could result from somebody installing LED replacement bulbs or lower wattage bulbs.

Audinos wrote:

All my signals work correctly ('75 KZ400), but the right side flashes twice as fast as the left side. Usually this means that a bulb is out, but all of them work. The flasher is a standard thermal flasher, probably the original.

Another issue is that the "stop lamp" indicator is always on, even though the brake light works normally on front and rear brakes. Could these two problems be related?

Another issue is that the "stop lamp" indicator is always on, even though the brake light works normally on front and rear brakes. Could these two problems be related?

Am thinking the "stop lamp" indicator being referred to is actually the brake light failure indicator light. It's supposed to glow red during brake application and stay dark when neither brake is being applied.

A steady red glow during brake application simply means a brake is being applied. It does NOT prove the brake light bulb is functioning. So the rear brake light itself may be inoperable regardless of the steady red glow.

If the indicator flashes when it's supposed to be dark (no brake being applied) -- such as just cruising along and happen to notice it flashing -- the flashing warns of an existing brake light problem. Could be a blown rear bulb or wiring issue or fuse problem. The flashing is to warn and inform the rider of a non-functioning brake light.

In the present case where the indicator is reportedly "always on," am thinking perhaps the rear brake light switch is adjusted too tight and is thereby failing to switch off when the rear brake pedal is released to its normal non-braking position. If adjusted too tightly, the switch thinks the brake pedal is always being pushed down. If loosening the switch fails to allow it to turn off, maybe the switch itself is broken. Sometimes it helps to spray WD40 into the switch. New switches are available at Z1E.

Imo, the above is not related to the reported turn signal issue.

Good Luck!