ETZ 125 questions

[Lemonwedge21]

I'm new to MZ motorbikes having just got an ETZ 125 which has needed some repairs which I require help with.

Firstly, when I got the bike the wiring loom was not connected and I've done my best to wire it up using various diagrams and trial and error, but have come to a blank when it comes to the ignition wiring. My ETZ is a 91' luxus model and has electronic ignition but I have not been able to find a suitable wiring diagram yet and was hoping someone may be able to help? There is a sensor pointing onto a splined haft from the crank shaft with three wires (green, black and red from memory) which connect to the sensor and go to a small box under the seat where they go into the wiring but I think it may be after market as I've not seen one the same anywhere else? The other part I believe to be the alternator which has 3 black wires going to a box under the seat which seems to go towards the front of the bike but I cannot figure out the order these wires need to go in so some guidance would be greatly appreciated!

Secondly the clutch mechanism is very heavy. I haven't got round to checking it thoroughly yet but I've put it together and the level needs two hands to operate and doesn't disengage the clutch at all so was wondering if there's any common fault/fix for this?

Thirdly the oil pump appears to be broken and does not pump oil on cranking or any other method so was wondering if there is an engineering service to replace them or if they must be replaced and if so at what price and where from?

Many thanks

[Trogolodyte]

You can get new oil pumps from http://www.Mz-b.com or http://www.os2rad.com or you can look on ebay (on ebay the dealer tailender2 is burwins motorcycles, who are a specialist u.k. based Mz spares dealer), but remember that the mikuni 2stroke oil pump fitted to Mz's only put out a tiny amount of oil per revolution of the engine (works out at something around a mug sized cup of oil per gallon of fuel) ( http://www.ost2rad.com/MZ-Spare-Parts/C ... TZ150.html ) also another good thing to know is that a etz250/251/301 oil pump will not work with the 150/125 engine.


I think I have the order of wiring for the early electronic ignition system written down in my haynes manual, as I had a similar problem with My 301 engine and I think it may be the same system (with a slightly different stator) as the lower part of the picture in the web link below. I will check it against what I wrote down when I disassembled my etz 301 and get back to you tomorrow.
http://www.ostmotorrad.de/schaltplaene/ ... an_12v.jpg

with regards to the clutch, I am sorry but havent touched a Etz 125 clutch in nearly 20 years and cant remember the details of them appart from the use diaphram spring and three bolts...

[Trogolodyte]

Ignition circuit / ignition sensor, The wires on the electronic ignition sensor should be green black and red (looks a little like brown when old and faded) left to right they should be connected this way, on the connection on the block on the stator, start on the end that is to the left/rear of bike, left = black, middle = green, and the right one (towards the front) should be the brown/red one.

The three black wires are the charging circuit, they connect to the rectifier diode plate under the saddle, it is important you get them wired up right else your bike wont charge. Attach a peice of masking tape to each of the the three black wires at the stator end and mark them U V and W. Then use a multimeter and find the other end of each black wire and Mark them in the same way, so you know the the wire marked U at the stator leads to the wire marked U at the diode plate. There are three spade connectors on the diode plate that should be marked in the same way Ie:- U V & W, connect the diode plate in the same way so that
The stator is marked the same, three spade connectors U V & W, just make sure that the wire you maked as U is connected to U on both the stator and the diode plate and the same for the other two and you should be OK... I think, the only way it will be different is if you have the model that has a rectifyer built into the stator (looks like a small green printed circuit on the bottom of the stator)

[Trogolodyte]

Hope the info works mate