Engine Knocks after changing to electronic ignition

I recently moved away from points to an electronic ignition on my 1975 tiller. It has a B&S 80202-0659-01 75110303 engine. 
 
Changed over because wasn't getting a spark. 
 
Runs now but with a very severe knock. Never had this before.
 
Wondering if the two could be related (timing)? Actually hoping it's related and not mechanical.  
 
Really would like to avoid a tear down and hoping the cause (and remedy) is obvious to the experts on here..
 
Thanks in advance for your help.
 
Jeff 
 

Thanks Scott for your reply. 
 
We're thinking alike here...
 
Here's what I did after starting it the first time and hearing the knock: 
 
I went back and confirmed the gap was at .010" and removed the shrouding on the drive side of the 'tiller because that's were the knock seemed to be coming from. I really hoped that was it. I also removed the vertical governor vane just in case it was the cause of the knock.  I also checked the fly wheel. It's on tight and it's not missing any teeth.  The clutch seems to be working OK (lubed it).  
 
I then started it again and the knock was still there.
 
It was then that I posted my question the this forum. 
 
I hesitate to start it again as the knock is pretty severe. 
 
I'll double check things again. Anything else I should be checking and since you didn't mention timing, should I discount it as a possible cause?
 
Thanks again for your prompt reply, Scott.
 
Jeff
 
 

Good suggestions, all, Scott....thanks!
 
I'll let you know what I uncover.
 
Jeff