I am having running issues and starting issues that I think might be the CDI but just trying to rule out anything else.

So a few weeks ago I took by bike out (93) and it lost power, got slower and slower before the engine cut out and stopped. Left it about 15 min got it started and made it another mile same issue. Noticed that the exhaust from cylinder 4 was cold. left the bike to cool and tried again but didn't start.
Checked the resistance on the coils, primary was good around 4 Omh but secondary was over range (yes I had changed the range on the multi meter to kOmh!)
I replaced the coils and the bike started, ran would rev fine in the garden. Took the bike out and rode 6 miles to meet with friends, pulled great and all was good. Stopped for 20 min for a chat before setting off for another 3 miles and bike lost power got slower and slower before stopping and not starting. Exhaust from cylinders 3 and 4 were cold this time. For clarity I have numbered left to right 1-4. Cylinder 3 and 4 come from different coils which is why I am confused.

The only thing I can think of is the CDI as it will work for a bit and then not and maybe a issue that means odd cylinders wont fire. Has anyone got any other suggestions about something that I might be missing? Or where is good to get a CDI from!

Thanks

When you replaced the coil packs, did you replace the HT leads? Were the coil packs new or second hand? Also, check the condition of the spark plugs.

I'd be inclined to suspect that the HT leads are failing when warm or there's a break in the ignition wiring somewhere around the engine that only makes it's presence known when everything is up to temperature. The symptoms don't sound like CDI (it's away from any substansial heat) and I can't remember ever having seen a failed Honda one. I've known plenty of Kawasaki and Suzuki CDIs/TCIs fail though.

HT leads were new with the new coil packs. I did reuse the angled plugs that attach to the spark plugs and the plugs last time i checked about 50 miles ago were good..
I have just gone out to check the bike and it started fine (with a slight mocking tone!) . Left it running for 5 mins and I switched it off. Looks like it is heat related so I have a fun few hours checking connections!

But wait! There is more... In case other people have this issue:

I did not get to find the fault in the end so I admitted defeat and took it to a garage. They couldnt find the fault but did check over my work and found that the carburetor Inlet Rubbers that were new on had deformed and melted. A couple of them had shrunk to tiny holes. Quite annoyed that new rubbers would fail so quickly. It had done about 30miles since they were fitted. Garage orded 2 other sets from the same place I got mine from and couldnt fit them because they were of such poor quality. Got genunie parts and all is good.

So in short, steer cleer of wemoto for now. Seems like there quality control has gone to crap.

O.E is the way to go, I know it’s expensive but for certain parts like rubbers and gaskets it’s definitely worth paying for something that has been designed and made to fit the bike not something that has been copied and should fit

it is good to know the root cause and I reckon with a lot of these bits - I would order OEM anyways. If Honda see a lack of demand, however small, then the decision to stop making them or having them available is easier to take.