Ok, we tried the coil from the 1VJ, no difference, both showed the same (correct) impedence. The CDi from the 1VJ has different output wiring to the 3AJ, so we couldnt try that. The mechanic is going to have a look at the stator to see if it is gunged up. If not, would the 1VJ stator be ok to try (with its CDi) to try and rule that out?

The bike can have a good blue spark one minute, then a crappy yellow one the next. Would the CDi cause this, or would it just die if not working? Weve been over the wiring with a fine tooth comb to check all the connections and check for broken wires, cleaned some up, but still the same result.When the bike is running it gives a healthy 13.3v at the battery, and switched off, 12.5 volts.

Really beginning to do our heads in!


Pete

Pete,

Has all the makings of a great saga by now.

Still wondering, before the top end replacement, did the bike have any sympton then of a malfunctioning ignition?

If you just swap the sidecover of the 1VJ for yours, and the CDI, with some temporary wiring you'll probably be able to get a functioning ignition system. I checked the wiring diagrams for 1VJ and 3AJ, and they are almost identical with respect to the ignition. So, by cutting and connecting wires you could also make the 1VJ CDI fit to the 3AJ. Afterwards, make sure to solder all wires back to each other and use good insulation tape to protect the connections. Although the wire colours (might) differ, the stators are identical, here's the translation table for the colours (wires on CDI, not stator!) from the diagrams I have:

3AJ - 1VJ
alternator: 3 x white - 3 x white
pulse to coil: orange - orange
stop signal: black / white - black / white
from clutch switch: blue - blue
from sidestand switch: blue / yellow - blue / yellow
pickup 1: white / green - white / green
pickup 2: white / green - white / red
central pickup: green - green
charging wire +: red - red
charging wire -: brown - brown

Another thing that might be problematic, is the protections built in on the 3AJ:
- Sidestand switch: get rid of it; the two wires going there should be connected.
- Clutch switch: also get rid of it, don't know wether the wires should be connected or not.
- Emergency engine stop switch: is it OK?
- The relay under the seat collects the information from the neutral switch, clutch switch and sidestand switch enabling the CDI to pulse to the coil.
All this protects you from driving away with your stand out and doing other things that might hurt you. I removed this sh*t long time ago and never had an accident because of it. What's more, the older models did not have this at all and there's a lot of examples of people surviving ....

CDI's can fail partly, intermittently or totally. No way to test without swapping with another one.

I can only stress the importance of a systematic approach in this, otherwise your brains will be cooked, your wallet empty and your bike not running in a few weeks ....

Succes!
Auke

__________________
Auke
http://aukemarieke.blogspot.com

Thanks for that. The bike stopped for no aparent reason before the head was changed, twice. The second time the breakdown lorry that came to pick it up dropped the bike off the back which is when the bike was stripped to get the work done! However, after the bike had sat for a bit and cooled down it ran fine. I thought the initial breakdown was due to the ht lead shorting on the head so we swapped the coil for a new one.

Obviously, the problem was not what we had thought and is raising it's horns more seriously now. The side cover is coming off tommorow to inspect the stator. I cleaned up the side stand switch yesterday to no avail, not checked the clutch switch as yet or the relay.

Thanks again

Pete

Checked the relay for the side stand etc today, it gives no continuity with either the ignition on or off.

Bypassed it, and the bike ran fine, but cut out (think it may have been due a short on the wires bypassing the relay) and now I have no neutral light, and no power to the ignition at all. Checked the main fuse, it was fine and all the other lights indicators etc work fine.

Any ideas?

Pete

There is a diode (could be resistor, I can't remember) that is embedded well within the wiring harness (just above the battery and slightly forward along the length of harness and not easy to feel for, at least for the XT600E) that was causing my engine to cut off whenever I hit the left side pod (can't quite remember whether the lights were affected). Cleaned and tightened the contacts and all were well. Hope it helps. Cheers.