Thanks so much for all the input. Really appreciated. Good tale there mark T. If only my bike would start and be secretly ridden!
Unable to do anything tonight due to family commitments and Manchester utd being on tv….

But I have made a nice list of things to check and do when I get in there. Maybe not quite time to get the petrol can and matches yet!

On inspection of the stator it’s had work that isn’t great and may need serious work. The wire from the points to the source coil/condenser looks too short and is very close to the crank/flywheel cam area. Could do with re-routing and lengthening. On the same area the points wire/source coil wire and output to ignition coil are not soldered to the condenser but all soldered together with a separate wire joining that soldered group of wires to the condenser. Isn’t right but I am told that electrically it should make no difference. It’s not right though and I should probably sort that out. I don’t know if it’s ok or not.

New connectors and some cable/wire on order.

I will let you know how it all goes but interested in other peoples more educated view on the condenser wiring.

I have tried to see a spark in the dark but no joy and I am not brave enough to stick my finger in the plug cap!

Thanks again one and all..

Ian.

In an early post you say red wire into the coil. I'm assuming the coil has only one wire in & not a two wire battery ignition coil? as red is a little unusual but if the only way in then all good. Coil secured tightly to the frame. Engine mount bolts tight from an all over earthing point of view.

Thanks RT325

The wire from the stator is black. Under the tank it has been terminated for some reason and extended with a red wire to join the red wire coming from the aftermarket ignition coil. There is only the one input. Ignition coil is new but will test anyway with meter.

Earths are certainly on my list to check.

I am awaiting some new bullets and some new wire to make up a bypass wire to get straight to the ignition coil.

Thanks again, ian

Aftermarket ignition coils have created MANY headaches for members here.  

Several have re-installed the original coil they had and it fixed their spark.  Perhaps someone could loan you a "known good" coil to rule that out?

Hi Markt

I have a RT2 here that I have swapped coil, plug lead and cap as well as plug. The RT2 has a great spark. I could fit the RT1 coil on the RT2 to really rule it out. I didn’t think of that at the time.

Thanks for the pointer and making me think of swapping over to the known good bike.

Many thanks.

Agreed, I have two shiny new knock-off coils that came with my DT-250 project. One did nothing at all the other would occasionally squeeze out a single feeble spark and give up. Both were in spec when measured with the VOM. Bought a used OEM coil for $7.50 and been sparking happily ever since.

Dear all
I haven’t forgotten about this but life has got in the way a bit for free time in the garage. Quick update. Not necessarily in order….

Tried 2 different coils. One known good off the RT2 and one new one. No difference

Tried different known plug cap and plug. No joy.

Ran wire straight from stator to ignition coil to avoid ignition switch and loom issues. All other stator wires disconnected. No change.

Removed stator plate and disconnected all wires from points/condenser/output black wire to take reading off stator coil. 2.3 ohms on my meter which looking around seems an ok reading.

Resoldered and lengthened wires to avoid contact with flywheel boss. Condenser seemed ok according to the meter. Points removed and checked over. Faces very clean and good. Seemed to open and close ok.

Checked resistance with flywheel off. Closed 0.4. Open 1.5. But seemed to vary when nothing else changed. As low as 0.9? This seems odd.

One other odd thing is the measurements takes across the points with flywheel back on. 1.9 open and closed! Is the flywheel trapping something? Or is my meter rubbish…

Tried other stuff probably too

Anyway someone I trust more than myself with electrics is calling round Saturday to check what I have checked with his equipment. Hopefully he will find something I have missed or got wrong.

It’s driving me mad….

Any other thoughts or observations are welcome.. thanks, ian

Your points are not making good contact when closed.  Should be a solid zero ohms closed and about 2 ohms open (points open reading can vary between 1 and 3 and still be ok).  Analog meters work best.  

Thanks mark.

Reading another thread on here I will try to clean again (even though they are new genuine and look really clean at contact area) and drag some suitable card through.

I am unsure if friend has analogue meter so will try to source one.

Thanks for input and patience. Ian

Things like this can be maddening.  Kudos to you for sticking with it and actually checking things!  If you decide to buy an analog (analogue?) meter, make sure it has the "Rx1" range setting for ohms.  (Some inexpensive meters have Rx10 as the lowest range, not good enough) Usually can be found fairly cheap.  Here in the US, Amazon has them for less than $20.