Coil on plug?

[Ivan]

Why wouldn't it work to buy some of these and wore them in series, paired 1&4 and 2&3, on our XS11s? Probably get the high output spark of teh better coils without the hassle of the wires.

FWIW they are stick coils off a CBR600

[xs11jack]

Good question, Ivan, I have been thinking along those lines myself. I think the primary side of the coil has to be a certain impedence in order to get the highest amount of voltage on the secondary side. Basically a coil is just a step up transformer. But there is more to it than that and my knowledge of transformer design is almost nil.
Come on guys help us out here.

[DiverRay]

Looking at them, it seems they had something to "rest" against in the Honda engine. The XS head doesn't have a water jacket, and the spark plugs are on an angle that may lead too the coil breaking. Just my first thought.....

[tw1980]

Don't know Ivan I looked up a wire harness on bike bandit and downloaded a cbr 600 wiring diagram.I'm not sure but I think Honda is using a CDI type ignition.If I'm right then the resistance on the primary is probably less than 1 ohm.You already know what that does to our TCI's.It would be nice to be able to measure the primary on one.I hope I'm wrong you have a good idea.

Terry

[Ivan]

Wiring the primary side in series would help with the impedance. But if it is CDI, then the primary side usually gets a lot more voltage than just the 12, so the coils may not help as much as hoped.

I also looked into some of the 4 cylinder DIS stuff and they seem to have low impedance on the primary side, but one interesting thing is that the older GM coil packs have a module that goes between them and the OEM ignition module, so I am wondering if that isn't something that converts the transistorized ignition to CDI. IIRC from the auto wrenching days those old GM coils had a 12V signal to the primaries.

If there is such a critter that can take a Transistorized ignition and convert it to capacitive, then our stock coils could very well make 60kV spark.

I shall be researching this soon.

I was just excited about the part where they had no wires.

[tw1980]

My concern is that CDI coils are pulsed only when they spark.Where TCI coils pass current threw the primary winding until the Ignition switches off and sparks.My guess is the primary on these coils wouldn't like the constant current flow.I still like your idea though,I'll have to think about adapting a CDI unit.It would be nice to find something that was easily adaptable and inexpensive.

Terry