Mechanic said I was running lean ??

[Redsvt]

Had my valves adjusted a while ago, the guy that did it stated my bike was running lean. Today I popped out the spark plugs to put new ones in, looks to me like it's on the rich side. Your thoughts fine people.

[csmith12]

Those don't look too bad, but... lean where? idle or under throttle?

[DannoXYZ]

Also lean where in RPM range? Idle? Low-end? Mid-range? Upper-RPMs to redline?

[ducatiman]

Originally Posted by Redsvt

Had my valves adjusted a while ago, the guy that did it stated my bike was running lean. Today I popped out the spark plugs to put new ones in, looks to me like it's on the rich side. Your thoughts fine people.

on precisely what did he base his statement?

[BoBO]

From the picture, it looks alright running a bit on the rich side. Running lean is like ashy-grey on the insulator tip all the way to being white. Also, rich mixture should have a darker insulator tip depending on how rich it is, compared to the picture you posted. Ive seen some black fouled up rich plug that smells like fuel, at that point the motor should be misfiring.

Pictures can be deceiving though, but you should be OK. My ninja 250 plugs were (light brown/Tan) which it a good indicator.

[Redsvt]

Originally Posted by ducatiman

on precisely what did he base his statement?

Not quite sure. That is why I am no longer taking my bike to the shop. His comments were about 10 months ago. The bike is 6 years old and has 18k miles on it. First plug change.

[JohnnyBravo]

Just eat more before you run, or quit running

[Ram Jet]

Originally Posted by Redsvt

Had my valves adjusted a while ago, the guy that did it stated my bike was running lean. Today I popped out the spark plugs to put new ones in, looks to me like it's on the rich side. Your thoughts fine people.

Appears to be fuel deposits not oil. I think it's running a tad rich but nice and cool and your exhaust valves will love it. I could live with it.

Bill

[KikRox]

Yep leave that alone. those plugs look a-ok to me. if it was lean those little babies would have a very light color to them like this, (or possibly whiter). The optimal area is between black and white which is a cardboard brown color but the bit darker like you have is fine. *EDIT* if you really want to know install brand new plugs and go for a ride and check them when you get home. it will give you a more accurate idea as to what your bike is currently doing.

[Triple Jim]

The trouble with just looking at plugs after riding for a while is that it doesn't tell you what throttle range is rich and what range is lean, it all gets mixed up. It just gives you a very general, average idea of mixture. If you need to use spark plugs to get decent information about your mixture, you'd need to do a plug chop at the throttle setting you're interested in.

Information about how to do plug chops is easily found on the web.

[Ram Jet]

Originally Posted by Triple Jim

The trouble with just looking at plugs after riding for a while is that it doesn't tell you what throttle range is rich and what range is lean, it all gets mixed up. It just gives you a very general, average idea of mixture. If you need to use spark plugs to get decent information about your mixture, you'd need to do a plug chop at the throttle setting you're interested in.

Information about how to do plug chops is easily found on the web.

With new plugs. A friend of mine who was a Honda dealership wrench says that you can't get an accurate plug read with today's crappy gas. Dunno.

[DannoXYZ]

Well, plug-reading is really inaccurate because it averages a long range of operating parameters. Even with a single-rev from idle to redline, it still averages the entire range. You can't tell which RPM is lean and which is rich. Often times, it's both and you need to tune each area independently. Here's an example of way too lean and way too rich.

[KikRox]

Good point jack, gotta tune each circuit independantly. the way i get around it with out a sniffer or dyno is to run three times, once at wot cutting the engine and rolling it in. check the plugs for how they look at WOT. then take it back out run it at half throttle being gentle but testing mid range and again cut the engine and roll it in and check again. then down to the idle circuit. fire it up let it idle for a few min and kill it then look again. and start making my adustments on my idle circuit. im not entirely sure the proceedure is proper but it seems to work relatively decent without a dyno or sniffer on hand. Gets me back on the road anyways. I should one day get my bike dyno tuned properly though i dont find it to be of great importance im not racing. i wish i was though hehe.