Quote Originally Posted by milton View Post
Just looked up the maintenance manual of JH600 from Jialing and found that the recommended plug is CR8E. Is there a reason why you selected CR7E instead?
(Don't know much about spark plug, but my Google search results mentioned something about the fact that CR8E is a "colder" plug. Does this have anything to do with your choice?)

By the way, all write-ups about spark plug want the plug "properly gapped" before installation. Is the new plug likely to need adjustment in its "gap", typically?

Cheers.
Hi milton,

my JH600 actually cam with the "hotter" plug, the CR7E from the Jialing factory. A hotter plug means in general, that the "optimum operating temperature is lower. Meaning, if you would ride the bike very hard, the plug might over-heat, burn or ignite wrongly.

I changed to the Iridium, based on a suggestion from Franki and some general research on the internet. I found, that especially idling and low rpm performance was much smoother.

The NGK homepage provides good insight and details on plugs. and there is another good information source here. I am happy with the improvement I got with the Iridium plug, but didn't look more into details since. It might be good to take a look at the plug after a good ride and judge it based on the details provided by those links. Well,... one thing at a time.

Greetings,
AW.