MZ ETZ251 battery + wiring

[alexxx]

HI,
Just got an MZ ETZ251, opened the battery case to find a couple of extra wires that I am not sure about.
The main battery leads are easy to id but the other two (black/red and black/blue)..no idea what they should be connected to, any thoughts?
Can the 1991/92 MZ ETZ251 be started without a battery? it is the 12 volt version with (I think) electronic ignition

Thanks

[Blurredman]

Those two wires should go to the indicator relay..

[alexxx]

Thanks, now I know I need to buy a flasher relay.
Do you know if these bikes should have a 9Ah battery.

Regards,
Alex

[Skorpion]

Hi alexxx,

The ETZ 251-301 came with a 5.5Ah battery.

The ETZ 250-300 came with a 9Ah battery.

I'm sure I've heard that a 9Ah battery will fit into a 251 you will just need to check the dimensions .

[alexxx]

Thanks to everyone for such useful information
great wiring diagram too.
I wonder why the later bikes had a smaller Amp hour rating, the trend is usually for more.
Will it be ok to use a larger Ah battery? just thinking of old japanese bike where the indicators and lights would dim so much at tickover and at night..virtually nothing but a dim headlight at tickover.
Never had an MZ before so not sure what to expect.

[DAVID THOMPSON]

did you mean an A not a V

[Blurredman]

I use an 9ah battery in my '90 251. It fits, physically in the provided space and although the headlamp dims a little at idle, it's no way near as bad as a magneto system. It's noticable, but not dangerous.

[alexxx]

Thanks to all.