jakobreid Posted April 4, 2010 Hi eddie.. 2004 crf 450r elevation 1000ft average trail riding only (tight single track) 165 main jet - needle NYCR 4TH no toil pre oiled air filters - quickshot 2 accel pump otherwise, the bike is stock. I put a new plug in, and rode trail for a few hours.. pulled it, and found what you see below. a 162 main is recommended up to 999ft, and a 162 beyond that. average elevation for the area is 1000ft. so is my next step moving to a 162 main? or moving the needle? this is what I found: I suppose this is what you would call carbon fouled from running rich. Share this post Link to post Share on other sites
Leardriver Posted April 4, 2010 165 is correct for sea level up to 2000. the needle is plenty lean at the standard clip position. A 162 is fine at 1,000 feet on an 80 degree day. Share this post Link to post Share on other sites
jakobreid Posted April 8, 2010 165 is correct for sea level up to 2000. the needle is plenty lean at the standard clip position. A 162 is fine at 1,000 feet on an 80 degree day. repair manual calls for a 162 above 1000ft.. Share this post Link to post Share on other sites
motodogg01 Posted April 9, 2010 (edited) jakobreid seems to be on the right track. I haven't looked it up but, I would defiantly say that's rich. However, from what I've read on th Internet and looking at the porcelain is seems a little rich everywhere. Take a few minutes and look at some of these links. There is a lot of info on how to read plugs. Of course, this should only be used as a guide to "help" confirm your suspicions of jetting issues. An aid to help you keep moving in the right direction. If you put to much stock/belief in reading these plugs they will sometimes lie to you. At least, I have found that the have lied to me. Just FYI. Almost nothing will beat the "seat and paint" feeler gage!! http://performanceunlimited.com/illustrations/sparkplugs.html http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp This one has all kinds of cool stuff on it!! look it over. The spark plug portion is toward the bottom and in the middle. http://www.4strokes.com/tech/ Edited April 9, 2010 by motodogg01 Share this post Link to post Share on other sites