Idea for a crank mounted electronic igntion

Snakeoil · Post by **Snakeoil** » Wed Oct 12, 2011 2:46 pm

I've been thinking about what it would take to build a crank mounted electronic ignition. The brain piece should already exist with the ability to set the advance curve in products like Sparx, Boyer, etc. The challenge for the 305 is mounting the firing mechanism.

I think the easiest place is on the end of the alternator rotor. Mechanical layout as follows.

Plate mounted to the alt rotor under the locking nut if there is sufficient threaded area to accept the added thickness. Otherwise, a special nut with the ability to mount a rotating plate would be required. To the plate would be mounted two small magnets 180 degrees opposed.

Mounted to the stator mounting bolts would be a stationary plate on which would be mounted an adjustable circuit board plate that would have the hall sensor.

It more than likely require either a spacer ring to move the alt cover out a bit along with some longer mounting screws, or just a new, deeper cover.

The system would be a lost spark system, firing each side on every stroke with the sides firing alternately 180 degrees.

The question is, would the hall effect sensors work in such a high magnetic area as the alternator? If so, this would make for a rock solid system with an electronic advance curve. The mechanical advance could be eliminated.

Any electrical engineers out there that could answer the question regarding the hall effect sensors working in that magnetic environment?

Gotta go research Hall effect sensors after posting this.

regards,
Rob

cknight · Post by **cknight** » Wed Oct 12, 2011 3:12 pm

There is a German crank-trigger assembly available. Check out elektronik-sachse.de for their offerings. The CB72/77 unit has 9 pre-programmed advance curves, and takes the standard advance mechanism out of the picture. Regards, Chase

Snakeoil · Post by **Snakeoil** » Thu Oct 13, 2011 10:05 am

Thanks. I've been talking to Dyantek and they gave a name to me of a guy that modifies their Dyna S to work on 305s. The S unfortunately maintains the stock advance mechanism.

Funny that nobody replied to my inquiry about Michael Stoic's electronic iggy. I would have thought somebody would have something to say.

regards,
Rob

davomoto · Post by **davomoto** » Thu Oct 13, 2011 10:10 am

Rob,

I have installed a couple of the e ignitions available on this site. They are an easy install, and the trigger is crimped and loctited on, and is very secure. They work well, and in my opinion are a good option for anyone that doesn't want to fool around with points. That said, I find that these bikes run so well when tuned properly, they don't need the e ignition. JMHO, of course!

Davo

Snakeoil · Post by **Snakeoil** » Thu Oct 13, 2011 10:18 am

cknight wrote:There is a German crank-trigger assembly available. Check out elektronik-sachse.de for their offerings. The CB72/77 unit has 9 pre-programmed advance curves, and takes the standard advance mechanism out of the picture. Regards, Chase

Thanks for that link, Chase. Looks like they already beat me to the punch. Pretty much identical to what I was thinking about. But then again, there are not a lot of options for that little area. Looks like it will work. But for $410 US, you can buy a lot of points and condensers.

regards,
Rob

cknight · Post by **cknight** » Thu Oct 13, 2011 12:17 pm

Hi Rob, like Davo, I've installed about five of the Stoic/Silver/Probe ignition systems on CB's. Everything has been straightforward, no trouble with the trigger wheels moving, and reliable. Used the Vintage Connections Honda style sockets and bullets to clean the wiring up for that factory look. I will admit to condenserphobia, having encountered some unhappy pieces in the 60's. Chase

Snakeoil · Post by **Snakeoil** » Fri Oct 14, 2011 11:53 am

I talked to a shop in Davo's neck of the woods on the left coast yesterday. They are working on a modification to the Dyna S that will allow it to mount similar to Michael's system, which is on the points cam. Yes, it maintains the old mechanical advance, but I would think the price will be more in line with what other higher market volume ignitions sell for which is in the $150 +/- range.

regards,
Rob