You need a 74,75 or76 DT250 complete ignition. Flywheel ,backing plate coils etc. . Slight change at the wire harness plug next to air filter. They don't come up very often somtimes you can find a motor that still has it installed.

The 1974 DT360 was an all new redesign. Older ignition from a 250 or 360 has a larger outer diameter on the flywheel that is a little too big to fit inside the 1974-on case.

People have done it... but it's not a straight swap.

Best compatibility is 74-76 DT250... consider installing a voltage regulator especially if you get a 1976.

You have to jiggle the harness to fit the points. However, I took the lazy bugger's way out and bought a "plug in and play" connecting harness from DEET here on the forum!

Also, if the earlier 360 at your local wreckers still has the upper chain guard, there's someone here on the forum who wants one!

excellent thanks for the information....
Al

OK, my son did all the standard checks on the pulser, CDi and coil and everything appears normal as per the factory workshop manual......
I reassembled the bike, set the ignition at 2.9mm before top dead centre with my trusty dial gauge [NOT ATDC] and it started up 2nd kick but was running backwards, thats right, running freaking backwards......again....
so I advanced the ignition another 1mm and its still running backwards.
what the hell am I missing?????? It must be the auto advance stuck on or something similar?????
Ive checked the rotor- the woodruff key is all OK, no slippage of the rotor etc.
I dont know what more to do..........
Al

Bikes in the old days would runs backwards if the timing was off, I guess try setting the timing retarded, like maybe try 1.5mm btdc, see if it run forwards. Maybe others will have ideas.

Hey Al Ive got 4 of these bikes with this ignition system sitting in my garage right now and the timing is set exactly the same as yours and they all run perfectly. I have had issues with a DT400 with this ignition kicking back and running backwards and it turned out to be a faulty pulser. I have a dt360 i am working on and I will make sure it works and I'll lend you the electrics to trouble shoot it if you want
Doug

Hi Dirt,
You stated “so I advanced the ignition another 1 mm”. For the test your doing retarding the ignition would make it less likely to run backwards. Also on the DT360 the flywheel running backwards is turning clockwise.

Hi Doug, that might work thanks....Im still looking for that box of DT parts but Ill get serious over the weekend and find it.
A friend of a friend has a new pulser sitting in the original Yamaha box but he wants $300 for it which is pretty outrageous so I wont be buying it Im afraid......not when I can get a complete system from Rex Electrics for about the same $.....
My son is coming around tomorrow and we are going to reset the timing again and see where that leaves us.
Al

Yes I moved the ignition pickup to the right which advances it.....And yes the flywheel is going to the right [clockwise] when its running backwards...…
Ill see what tomorrow brings.
Thanks again
Al