First as a long-time forum stalker I justed wanted to send out a big 'thank you' to the entire community here for the invaluable information this forum has provided in getting these old bikes running in top shape. My CB400T would still be sitting in pieces in my parents back yard without you!
Here is my situ. I recently upgraded the CDI on my 79' CB400T (recently rebuilt) to an ignitech dc-cd-ip2 unit from stock and am encountering an issue with what I think is a preignition / timing problem at startup. Here is what happens:
1. Pressing start button with kill switch off results in what I would describe as a rough start. Starter gear can be heard intermittently grinding and the bike eventually starts (where no start problem exists with the stock CDI). Bike will also intermittently backfire through the carb with a plume of white smoke on start. No issues at all using the kick start however, it cranks over and starts just fine.
2. With kill switch on, the bike also cranks over without issue, bike doesn't start (obviously) but no start gear grinding occurs at all (hence my suspicion there is some early ignition issues going on).
Once the bike is running it idles a bit rough (vs stock CDI) but when up to speed it runs completely fine.
My question to the Honda twin wizards out there is does this sound like a preignition / timing problem related to some ignitech settings I've bollixed-up and if so, are there any CB400T owners out there who have successfully gotten an ignitech unit to work who are willing to share any learnings?
I'll follow up with the advance map but base is set to 10 degrees with most other settings on defaut. Wondered if anyone knew if this sounded like something obvious who are more experienced with these units.
Thanks in advance.