Topic: Dyna S on a '79 CB750 F.

[thrutheframe]

I bought a '79 CB750 F that was a borderline basket case.  I won't go into the whole saga of troubles the bike had but it was $500.00 and worth not a penny more.  Last week I finally got it started and discovered that cylinders 2/3 had no spark.  Obvious problem with ignition coil 2 or something inline in front of it.  Once I chased it all back to the ignition plate I determined that the Dyna S (installed by Hamfisted PO) was to blame.  I wanted to see if there was a test to determine if the unit was bad.  I called Larry at Dyna and told him my issue and his initial response was "Why do you want run a Dyna S on that bike..."  He proceeded to inform me that the Dyna S does not tolerate oil and is not recommended for the twin cam Hondas. 
  Has anyone else run into this situation?  I don't want to go back stock if I can avoid it.  Any recommendations on an after market ignition for this bike?


Queen City Classics

[BobbyR]

He is full of #$%*. The Dynas made in the recent past are notorious for dropping 2&3. The old Dynas were bulletproof.

I had a problem and did a web search and found they are crapping out all over the place. It can run great until you get it warmed up and then they drop cylinders.

Do Google search on Dyna S problems and you will see what I mean.  I went with PAMCO. 

[thrutheframe]

It could be new, old, I have no idea.  It was on the bike when I got it.  The important thing is I need an ignition that will tolerate oil.


Queen City Classics

[thrutheframe]

On a DOHC honda the area behind the points cover, while not under pressure or part of the sump is an oil splash environment.  SOHC it is on the other side and dry.


Queen City Classics

[thrutheframe]

Twin cams are electronic ignition.  I didn't design it I'm just turning the wrenches. and it IS bad, I tested it so I need something I'm cofident with.  I messaged pamco Pete here and he directed me to CB750ignition.com.  I'm waiting for him to reply re: my oil splash concerns.


Queen City Classics

[thrutheframe]

Again already tested it before posting here.  I'm not one to run sonething on a bike that the manufacturer directly says not to.  Sorry that you're not understanding my concerns. I appreciate your input.


Queen City Classics

[scottly]

Thru, if I were you I would try to get the stock pick-up plate and advancer parts. The pulses produced by the stock triggers will operate off-the-shelf GM HEI ignition modules.