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Discussion Starter · #1 ·
Here are a couple of home brewed pointless ignitions for vintage bikes. The first is is for a CB450/500T. Pointless ignitions for these are usually pricey and some not very reliable. I had a Nuetronic on my race bike and it went well until it got really wet and it never worked after that.
On 360 degree crank parralell twins you can use one trigger and a dual output coil (like off a harley, avalable at flea markets for next to nothing!), but on 180 degree crank you cannot (or so I have heard). What you need is two seperate ignitions. With slight modifications to the base mounting plate it is possible to fit two Pertronix Ignitors on the CB450/500T points plate at 90 degree angles. In this example I fabricated a jig to make sure both ignitors were drilled exactly the same, a new blank points plate, and a rotor to replace the points cam (must be non-magnetic, I used Delrin), and sink one magnet in it.
Yes it takes some skill and some machinery, but it was not real difficult. Check out the pics

Here is another system for 360 cranks using Compufire or Empi-Accufire Units. Will work on any 360 degree crank paralell twin. In this example on a XS650. Mount the unit using an exsisting threaded screw hole, drill a hole for the indexing dowel on the back of the trigger, fabticate a new points cam that excepts the rotor, punch out two of the magnets and install a dual output coil and that is it. Check out this pic

In both cases I used ignitions designed for air cooled VWs with the Bosch 009 distributors. Empis go for about $40 on Ebay, Compufires for about $70 and the Pertronis for about $80. It may take a bit of messing with the plate or rotor to get the timing in the zone but once you do you never have to adjust it again.

Good luck with your new ignitions.
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