New (hopefully) observation on weak HT 80cc motor - anyone seen this ?

[arceeguy]

Just want to jump in and remind everyone that reading the plug is only accurate if you start off with a new plug and perform a "plug chop". I've seen plenty of engines with wet, oily plugs that suffered from "lean bog" and needed a larger main jet. The fix in these cases was lowering the jet needle to lean out the low/mid range and enlarging the main jet to fatten up the top end.

I'd hate to see someone seize up an engine because they thought they needed a smaller main jet from a misdiagnosed plug reading.

 

[TREEWK]

Arce, Good Info. And Correct. Ron

 

[AussieSteve]

Somewhere on this site there's a good description of how to do a plug chop, with a link to a good series of pics of plugs in various conditions.
I'll see if I can find it and add it to the 'HT Engine Specifications' (manual) thread.

... Steve

 

[happycheapskate]

http://video.google.com/videoplay?docid=-6524875525755613771#
Explanation of "plug chop". Man rides moped and does test on spark plug visually.

shortened quote
I'd hate to see someone seize up an engine because they thought they needed a smaller main jet from a misdiagnosed plug reading.