Spark plug difference and any issues?

[Windmill John]

Hi All,

My 1981 CM400A has DR8ES plugs fitted.
Both manuals I have say for 1981 it should be D8EA and DR8ES is for 1982.

As far as I can tell, the difference is the DR8ES is a resistor style plug.

Are there any issues running these rather than D8EA in a 1981 model? I know from my Airhead BM days, you would be best matching the plug cap/plug to the coils fitted.

 

[LongDistanceRider]

Use the D8EA plugs only. The DR's have 5K ohm resistance coupled with the 5K ohm resisted caps = 10K resistance and a weaker spark.

 

[Windmill John]

Thanks Jim, same issue with BMs.

 

[Alan F.]

Or you could use them with non-resistor plug caps.

 

[Windmill John]

Thanks Alan, I’ve just ordered a couple of plugs. I mean… I’ve spent enough blooming money so far!….
… Wish I’d check which caps I have…
I think I’m designed to keep emptying my savings!

 

[LongDistanceRider]

Thanks Alan, I’ve just ordered a couple of plugs. I mean… I’ve spent enough blooming money so far!….
… Wish I’d check which caps I have…
I think I’m designed to keep emptying my savings!

You should have XD05F plug caps