What is the relay for the coils for? Does it keep the current from going through the handlebar controls?
Z1/KZ ignition switches, and motorcycle ignition circuits in general can introduce voltage drop at the coil primaries, reducing spark energy.
The relay bypasses the ignition and kill switches, in order to supply full battery power direct to the coils through the NO relay contacts, while still retaining operation of the kill switch. The harness we developed is plug & play, with no butchering/cutting/crimping of any OEM wiring necessary; we just crimp matching bullet and ring connectors the the relay harness and battery power connections, respectively. The relay harness can be simply unplugged from the main harness and coil wiring, enabling the bike to be returned to it's factory original wiring configuration in under ten minutes after the tank is removed.
We were compelled during the resto of our '72 Z1, 'The Seven Year _itch', to disassemble an OEM ignition switch to correct an intermittent issue. The internal construction we found suggests that the design of the rotary contacts was barely adequate, at best, for the current load imposed, particularly on the circuit feeding 12V to the coils. See our post linked below: kzrider.com/forum/4-electrical/606810-z-...-and-troubleshooting
slmjim & Z1BEBE
A biker looks at your engine and chrome.
A Rider looks at your odometer and tags.
The Sohc Hondas suffer from similar electrical issues. I think I will solder up a relay for the start circuit on this Z1, seems like a safe thing to do for increased reliability. Thank you all for the great information.
I’m looking over details on the carb hoses.
the bowl overflows gather together and drop down over the back of the motor toward the swing arm.
where do the two 6.5mm bowl vents go besides just up? They are listed as 140mm long in Brookes.
On another note
i am trying to get a machinist friend of mine to make me a set of the nylon choke plunger collars. If he is interested I may try to get him to make more of whichever style someone needs, would any of you be interested?