A question for you bike engined guys running cop coils which I will presume is probably all of you. I'm in the early stages of changing a engine over to a cop coil system for neatness more that anything else, looking at the coils online it seems they all fit in the head/cam cover via ribbed rubber ( no innuendo comments please ) sealing rings, now presuming they are all the same diameter I need that dimension and the dimension of the main body directly under that section so I can turn up some adapters

Cheers

Shooter

I have an R1 4XV engine in my Locost. It came to me with the original twin wasted spark coil packs. I found the COP sub loom from a later 5PW R1 in the box of spares that came with the car and the loom from the ECU had the matching plug and matching wire colours to the 5PW COP loom so I guessed the previous owner had been planning to change it to COP. I bought a set of pencil coils from a later "big bang" R1 as I was told they are physically and electrically similar. I can confirm they fit in the head perfectly and connect to the loom connectors. Next time I'm near them (the car and the various bits are stored across town at my MiL's garage!) I'll measure them. Worth noting that R1 pencil coils are "dumb" so need an external igniter to run off most standalone ECUs. When I found this out I went back to external coil packs/wasted spark using a Polo coil pack (built in igniter) and I'm using Ford Focus Mk1 leads which fit the R1 head perfectly too(once you add the screw on ends to the spark plugs) and fit the Polo coil too.

So, what I'm saying is, for an R1, the head recesses seem to be similar for early and late R1s and also similar to Ford Focus so there seems to be some kind of standardisation in sizes!