Ducati Monster Motorcycle Forum banner

1 - 18 of 18 Posts

·
Premium Member
Joined
·
3,677 Posts
Look at the white porcelin around the center conductor. If you see fine spray of silver spots, then you're too lean. That's aluminum swept off the combustion chamber from detonations. This can happen without making a sound. (I've seen it) IF you don't have this, then you're not really too lean, you're just being frugal.

:) Chris
 
G

·
Discussion Starter · #6 ·
you're awesome. thanks. No silver..... the top electrode is brown, but one is a little white...that is all.....you have eased my mind a bit ......... oh man, I was htinking it was time for a major engine rebuild LOL I was thinking, there goes my new rear shock, brakes, forks.....
 
G

·
Discussion Starter · #10 ·
Thanks !!

Ducati.com has an article about how to read plugs. They say that the carbon build up is due to leaky valves, etc....

You think there is any truth to this ?
 

·
Premium Member
Joined
·
5,076 Posts
2 problems with trying to answer your question - with unleaded gas, you don't get the same kind of coloration as with leaded gas, & the plugs tend to look "leaner". The other problem is that you cannot really tell how a plug is burning (other than obvious stuff like Chris pointed out)without looking deep into the plug at where the insulator meets a metal ring. You need a lighted magnifier to do this properly.
 
G

·
Discussion Starter · #16 ·
I got a question, if I am running lean, should I downgrade in my gas selection ??? from 91 to say 87
 

·
Registered
Joined
·
45,105 Posts
octane has nothing to do with rich or lean. it avoids ping (detonation). just use the lowest grade that avoids ping. 87 will probably work.
 
1 - 18 of 18 Posts
Top