Alternative coil for airhead?

[The Other PaulG]

Thanks Ian, I think that's the route. If I get it right, I'll document it...

 

[ianboydsnr]

Thanks again guys for all the great info - it well help others who might ask the same question in the future.

OK so....

I sourced a K100 coil (two, in fact, so if all goes well and you need my spare one, let me know).

The original coil has 2 connectors, one with a twin black wire and one with a single green wire (pic 1). This is exactly per the manual (pic 2) so it suggests I'm starting with a standard set-up. So far so good.

The K100 coil has three connections. The one on the left of pic 3 is marked '+' and '15'. The one on the right, facing the first, is marked '1'. The one at the bottom, between the other 2, has no marking. This is the coil that powered plugs 2 and 3, by the way, if that makes any difference.

Please, can anyone who has successfully carried out this conversion, tell me how to wire the existing R100GS loom to the K100 coil connections?

Thanks,

Paul G

The two at each side connect to where the original R100 was connected, it matters not which of the R100 wires you use, the center is merely earthing the coil, as it's rubber isolated on the mount, which can be ignored, unless you rubber mount it on the R100!

 

[Steptoe]

BTW, I can see that common sense would suggest that I match up the 1 and 15 on the K100 coil with the 1 and 15 on the R100GS wiring diagram, but I don't know whether that 3rd connector needs to be incorporated / bridged too.

Garry H you mention a small adaptation, what is that?

Paul

Thanks, but I was referring to the third connector on the K100 coil, rather than the third wire on the R100GS loom.

Can anyone definitively tell me what the correct connections are, and what the required modification is?

Thanks,

Paul

Modification is the mounting bracket, not the electrics. Wire it up in the way you've already stated, ignore the third terminal.

 

[The Other PaulG]

Thanks all for the good advice.

Great, OK so I wired it per the description above and all works perfectly, including the rev counter.

In terms of the modifications, the ones I made were:
1) I removed the two surplus mounting lugs from the K100 coil. Bear in mind they're only surplus because of the particular way I chose to mount the coil, but removing them made positioning the new coil a little easier. The pic below shows a before and after de-lugging.
2) A couple of simple L-shape brackets allow the coil to fit securely, tucked under the frame in the same position as the original.

I do have an extra K100 coil left over - if anyone can use it, donate the £4-odd postage to Bakerman's charity I'll send it to you.

Paul G

 

[Kenny]

Cracking update Paul....big thanks to you and Steptoe for this. Thinking of replacing the two coils on my 1986 R100RS..I wonder if this can be done with this single K100 coil ?