Topic: Ignition? Coils? Kill switch?

[shouse76cb]

Hi all,

I have a question about my '76 cb750. I was riding the other day and after 30 or so minutes at highway speed it felt like it dropped a couple cylinders. I pulled over, she it off and restarted it and got home without it happening again. Then yesterday it happened after only a couple minutes running..wasn't even up to operating temp yet. It has a dyna s, 3 ohm coils with a HM resistor pack. I did a search here on the site about this and i found out others have had this problem with the dyna. How do I test if it's the dyna, my coils or possibly my killswitch causing this? My killswitch is kinda notchy as I have to toggle it in order to get it in the spot to where I can kickstart it. Any help is appreciated, thanks

[bollingball]

If it were the kill sw, ALL the cyl. would stop. The kill sw. feeds power to one coil then a small jumper goes over to the other coil Sometimes that jumper is not tight or dirty and one coil will drop out.Check all your connections first. Sorry no help with dyna I still like my points. Hoping for a Hondaman setup for Christmass. How good of shape is the battery, Is there some kind of advantage of 3 ohm coils with the resistors over the 5 ohm coils? Your correct a lot of talk about dyna QC.

                                           Ken

[shouse76cb]

Thanks for the reply...I'll check that jumper wire and my connections around the coils. I hoping for a good Christmas too, I'm thinking Hondaman ignition and new stock coils maybe.

[bollingball]

That is the setup I like going back to stock on the side of the road if you have to try that with any others.

[shouse76cb]

I'll check out the battery as well. It's relatively new but could still be part of the problem. Having the option of going back to stock on the side of the road if needed i like as well. Honestly I bought the dyna and 3 ohm coils as soon as I got the bike without doing my research on it. Then got the resistors to get it to where it should be. This is my first bike and has been a learning process to say the least!

[ekpent]

Could also be a fuel flow issue as I am hearing some things like "it felt" etc. and other assumptions.The fact that it ran better after resting may point to that as in filling float bowls etc. Carry an extra spark plug or two with you and when it happens again pull over and put a different plug on the suspect wire,can leave the old plug in and see if its getting good spark. A temp test on the headpipes should show if one or two is losing power. Hope you don't have one of those bummer Dyna's we have been reading about.

[CoachDoc]

I believe you can bypass the kill switch in the headlight bucket.

[shouse76cb]

Thanks for the replies! The fuel issue is something I'll checkout as well. Actually the first time it cut out on me I had just run it up to about 80mph for a few minutes then it happened. I'll check fuel line routing and float level. I thought fuel until I starting reading some of the dyna issues, hope I don't have one of those bad units either. If so it looks like one of HM ignitions and back to stock coils

[CoachDoc]

I have the Hondaman ignition with Dyna 5 ohm coils. Very happy with it, and of course the plug leads can easily be changed in the future.