Plug chop... BS?

[jstone]

http://www.strappe.com/plugs.html

"...A lot of amateur tuners, some of whom are fairly successful, will look at some plug freshly removed from a two-stroke engine and offer advice based on the color of the oil deposited on the insulator nose. In fact, if the plug is hot enough there won't be any color, and if there is that still has nothing much to do with air/fuel mixture. If you think about it you'll realize that the only color you can get from an air/fuel mixture is the color of soot. When the mixture trapped in an engine's combustion chamber has more fuel than can be burned with the available air, then combustion will be incomplete and the excess fuel will remain as soot, which is not brown or tan or magenta or any color other than black. And if your engine's mixture is too rich, the sooty evidence will be present on the spark plug's insulator, in a very particular area...."

I guess its just one guys opinion, but i think he knows his stuff.

[tru72]

finally correct information.....
when i read plugs there is no way i just look for the color.. I actually cut open plugs to check the "fire ring"

[PimpinSpree]

care to explain that "ring fire" thing? how does that guy recomend checking how your motor is running?


still it seems like color will give you a close indication

[keithw]

IMHO, richen it till it starts to four stroke then lean it out just a little. Check the plug deposits to select the heat range of the plug. With the proper heat range plug, rich will darken the plug and lean will lighten it. If you are doing any mods and you don't have a selection of jets you are asking for big trouble. For engine life you are way better off a little rich than any lean. If anybody is interested I can post the Honda part numbers for main jets from 62 through 85.

keithw

[PimpinSpree]

any good place to order them online. They are like 7 or 8 dollars a piece from my honda dealer

[keithw]

I order them from the online bike and Honda power equipment places. 7 to 8 bucks each is about what they run. It runs into a little money if you get a decent collection but they are so handy. Once you get over 85 you need to hand drill them, at least I haven't found any OEM ones that big. I prefer the OEM ones as the holes are more precise and they have the size stamped on them. Once you hand drill them you have to remember what size they are. In my jet kit I have a seperate little zip lock bag for each different jet with the size written on it.

keithw

[Kenny_McCormic]

Color does give a close enough thing, but a temp gauge is the best way to do things.

[keithw]

What temp gauge do you reccomend? I understand there are some that install under the spark plug or a head bolt.

keithw

[Mattedroom]

Keith, post those numbers!! Please. My local Honda dealer is no help to me finding them, even sold me one that doesn't fit. I don't know where else to look.

[keithw]

62 99101-ZG00620
65 99101-187-0650
68 99112-GHB-0680
70 99101-1870700
75 99101-1870750
80 99101-187-0800
85 99101-1870850

The first two numbers are the jet size, then the Honda part number. Some of these are Honda power equipment jets. Google the part numbers and you can usually find a dealer with them. The last four digits are the jet size. If you root around with part number searches you might find more sizes.

keithw

[PimpinSpree]

and where do you get drill bits to drill them?

[keithw]

I found a tiny metric drill bit set on ebay. I expect a good hobby supply place would have them also.

keithw