[DT175 mx CDI]

In the mag

Ignition pulser coil W/R - B = 12.4 Ohms +-10%

Charge coil Br - B = 420 Ohms +-10%

. R - B 13.6 Ohms +- 10%

Orange from CDI to coil LT

You say the bike has been used off road, what means of stopping the engine has been used, maybe theres a switch in the off position, this is done by switching the B/W CDI wiring to chassis.

Thanks for this.

The kill switch was connected but I have disconnected that. I have cleaned up all of the connections to the CDI (the CDI was not connected when I got it) and earths that I need and with a new plug and it sounds like I have a spark. There is no 2 stroke oil in it or fuel pipe so I will need to get these. I may have to wait until it gets dark and then kick it over with the plug out but earthed to see if I am right about the spark. Thanks for the information so far.

I sent my other half and her kids off to the pictures so I can get some time with the bike. I only brought it yesterday and love it. Non starter and rough as old boots or not.

Cheers but I am sure that I will be asking more questions in the future.

Bad wiring pictures below

[DT175 mx CDI]

You need to expand on 'butcherd' but here is a quick discription:

there are 2 systems,

the 2K4(78-79) and 2X2(79only) Dt 175mx had the following:

Brown, red, white/red,black They come direct from the mag.

orange, black/white, black, come out of the loom.

The 4J4 (80-85) Dt175mx and the Dt125mx (4J3) of the same period had the following:

Brown, white/red, black. They are direct from the mag.

Orange, black/white, black, coming from the loom.

All of these bikes have the orange feeding the coil, the black and white kills the engine via the handlebar stop switch and the black is the battery return/negative.

On both bikes there is also green/white, light blue and yellow.

The yellow being the lighting feed to the ig switch, the light blue the neutral light earth and the green and white which turns to white in the loom?? charges the battery via the rectifier.

Some of the 125s had points.

By butchered I mean that the bike has been used off road and no battery no, presumibly a total loss system?

There is no headlight and a lot of the wiring is connected by connector blocks. The frame starts 2k4 (The frame and engine numbers are matching)

As per the picture I have Green, Yellow, Brown, Red/White and Black coming from the Mag. The orange appears to run to the CDI which has 2 sets of 3 wires.

Brown, Black and White/Red

and

Orange, Black/White and Black.

The Orange wire appears to go to the coil which has 1 LV wire.

If I put a 6v tester to the mag and earth and kick over there is power from the mag from the Brown wire. The rest appear not to be producing power but this may be down to a bad connection.

I cant really test for a spark as I need to shhot out to get a spark plug spanner as I don't have one but should I be getting any juice from anything but the brown?

Thanks

[DT175 mx CDI]

Yes 5 out of the mag and 6 go into the cdi, with the 7 wire version you have an extra red out of the mag going direct to the cdi.

I do have the 6 wires from the CDI bunched into 2 sets of 3. All I need now is to work out what I need to connect as the wiring is butchered.

[DT175 mx CDI]

....My engine is 1979 but the magneto has only 5 wires coming from it, and only one source coil (contrary to what the parts book says I should have) which makes wonder if I have a magneto from a different year, I don't know if this will be a problem or whether I just need to match the CDI to it.

Does anyone know anything about this.

Any help is appreciated.

Regards,

The one I brought today has a 5 wire also

I have just posted in another thread to see if someone can help me out with the wiring.

[DT175 total loss system]

Hi,

This is my first post so nice to meet you all.

I need some help with a DT175mx (I think. 1981 and the frame starts with2k4).

The bike has no battery and someone has wired it so it runs with a total loss system. I have seen some online wiring diagrams however my bike seems to have more wires than the diagrams.

The wires from the crank look like this

The coil looks like this

and the CDI (I dont know if this is right). looks like this

I would assume that the green wire from the crank goes to the coil but what about earths etc???

Thanks.