Pencil Coi;ls

[iceman]

George,
Those pictures were on the German link that was posted by skorpion.

Now I know why the heat shield is there by the exhaust !!

[Mach IV]

I think we need to find a Denso or Mitsu that will work.
I've converted a few ZRXs from regular coils to stick coils because of the reliability.
And they are cheap here,I get 4 for less than $100.
I can research it if you know the impedence of the stock MZ sticks.

[boilermaker]

Mach
We have found a couple of coils that will do the job (see other threads) but the information re the impedence etc has been difficult to track down as the original coils were made by SAGEM in France and supplied via Siemens in Germany to MZ. The problem now is that SAGEM were taken over by Johnson Controls and have no technical department to talk to. What we do know is that the same coil was supplied to a number of car makers starting with Renault and the coil now recommended as a replacement can be used (all V6 engines Renault/Peugot,Alfa. a minor mod to the mounting is reqd.)

[Mach IV]

Mach
We have found a couple of coils that will do the job (see other threads) but the information re the impedence etc has been difficult to track down as the original coils were made by SAGEM in France and supplied via Siemens in Germany to MZ. The problem now is that SAGEM were taken over by Johnson Controls and have no technical department to talk to. What we do know is that the same coil was supplied to a number of car makers starting with Renault and the coil now recommended as a replacement can be used (all V6 engines Renault/Peugot,Alfa. a minor mod to the mounting is reqd.)

No offense but I'd rather go with Japanese.
Does anyone have an MZ shop manual?
That should have the specs in it somewhere,maybe in troubleshooting.

[tomtom]

...

[boilermaker]

Mach
Page 235 gives primary and secondary winding resistance figures, also page 179. Not being an electrical man I do not know how to translate that in to the impedence and then to talk to a sales person quoting an impedence and hope they understand what I am saying because the usual response that I get is one of "what car is it for sir" followed by "a bike? we don't do bike stuff" at which point I usually lose both patience and interest.
I wish you luck

[Mach IV]

Mach
Page 235 gives primary and secondary winding resistance figures, also page 179. Not being an electrical man I do not know how to translate that in to the impedence and then to talk to a sales person quoting an impedence and hope they understand what I am saying because the usual response that I get is one of "what car is it for sir" followed by "a bike? we don't do bike stuff" at which point I usually lose both patience and interest.
I wish you luck

That's all I need,I'll post my findings here.

[speedshop]

I build ignition systems. The coil resistance is not as crictical as you'd think. The type of coil is more important. Coils are measured by their reactance. This is not easy to test so to give the mechcanics a chance at trouble shooting the static resistance of the coil is quoted. This figure means very little in terms of how the coil works when installed.

You'll find that manufacturers follow fads; on one type of igintion I deal with a coil with a primary of 1 ohm and a seconary of 12,000 was popular in the 80's. You will struggle to get this coil in the correct format now. However you can get a 0.6 ohm/8,000 coil that give the exact same output and does not place too much stress on the box.

Finding Japanese parts is difficult as the minimum order quantities from the factories is vast.

[djsbriscoe]

Hi Speedshop,
For curiosity how are these pencil coils driven? Is the current driving them just simple DC that's turned on and off or is it a pulse width modulated square wave thats turned on/off? I'm assuming the coil is driven directly from the EMU.
Thanks.

David

[speedshop]

It depends, some automotive systems are very hi tech and measure the coil's performance to see if the cylinder is firing correctly and adjust the spark to suit.

However, I can't imagine that level of system being installed on a motorcycle. I would expect to find these coils are nothing out of the ordinary and a very basic set up driving them.

If my time wasn't taken up by developing a high voltage CDi system for a re-phased XS650 at present I'd look in to this set up more and see what they've done. Underneath all the flashy hi tech exterior, very often you'll find some bit of standard electronics they have been using for the past 20 years altered so it can't be used on any other model!

[iceman]

I know if I needed an ECU for the MZ the first thing I would do is a stare and compare with the unit on my Aprilia Futura which uses a Sagem unit.

Problem is getting to the point where you think the ECU is bad is usually the very last thing you look at because it always has to be" something else"

Last year when I went on my xcountry trip to get my MZ i had a call on my machine from my local Aprilia dealer when I got back.

They had a customer with a Futura and came to the conclusion it was the ECU and asked if they could use mine to prove it.

As much as I like those guys I didn't return the call as I made my living as a telecom tech. for thirty years I didn't want mine being used as the test mule.

ECU's are fine when left in place it's when someone that's not sure how delicate they are when off the bike handles it in the wrong way.As little as a static discharge and I would be looking for a new unit.

[speedshop]

well possibly- but they are very well protected, you are supossed to leave them connected if you have to do welding. The circuits are that well protected. Disconnecting them causes more problems.

With digital stuff you can bet your bottom dollar it ain't going to work on another model, its so easy to program it not to.

[boilermaker]

Speedshop
Are you sure that it is recommended that you leave ECU/EMU units connected when carrying out welding operations? I have known the HF energy emitted by the starter unit on a TIG set to fry a computer at a couple of hundred feet. Protection from such effects would involve the use of a substantial Faraday cage surely?

[peaster]

I tend to agree with boilermaker. Any Mig, Tig or arc welding with the ECU and associated microprocessors connected raises the possibility of accidental electrostatic discharge into the wiring due to the high voltage and current circulating. I would recommend removing the susceptible components - do this by earthing the bike properly and then use a wrist type esd strap (as used when working on computers - available from electronics components stores for a couple of dollars) connected to the chassis to place your body at the same potential. Careful removal of the components is no problem - place them into the sort of bags you get computer components in, e.g. motherboards, video graphics cards etc, to contain them and prevent any esd when off the bike. Just reverse to re-instal. I'd rather do this than possibly fry an ECU or controller, which will be infinitely more expensive to fix.

Anyone out there had any ECU issues on thier bikes. Mine is a 1000SF with about 20,000 trouble free km so far. Also can anyone tell me if Meyers in Hungary have taken over the bulk MZ spares distribution ??

Cheers ....

[boilermaker]

Peaster
I was speaking to Ian at Grahams M/C yesterday and he was saying that they were still being used as the main international outlet for MZ (four stroke) spares. He is still not impressed by the lack of communication with the present MZ management.