spark plug reading help

[wanta86r]

should the entire porcilain part be dark, or only a small ring toward the bottom

[bigredhead]

and all this time.. i was looking at the plug tip !!!... ie: the metal arm you bend or pull to set the gap....

heh..

[42F67N]

If you install a brand new plug and do the chop correctly * will pretty much only get a reading down inside of the plug,a plug chop cannot be done correctly on a old spark plug thats been used it has to be brand new.

a plug that * have been riding on for a while also wont give * a accurate reading as there are diffrent throttle ranges that need to be choped and read by themselves.

[wanta86r]

so am i too rich if i am getting alot of color towards the top of the porcelain

[42F67N]

if its really black it could be your premix this is in a 2 stroke r right? what ratio and type of oil are * mixing?

I run my 2 strokes a tad rich not enough to effect the performance to where ya notice but enough to make sure im not gonna lean out.

[wanta86r]

its on an 86 atc 250r- i am running 32:1 castor 927 with 110 octane

[42F67N]

Jet your main down one more size and do a chop,put a brand new plug in the bike fire it over and take it for a chop get it running wot preferably up a slight incline to place the engine under a load get it into 5th/ 6th whatever ** top gear is go about 15 secs wide open then pull the clutch in and kill the motor but dont release the throttle or clutch till * come to a stop,pull that plug out and that will give your a proper reading.


32:1 should be ok but id shy away from castrol oils they produce alot of carbon,i burn yamalube which isnt to bad but the best is amsoil.

[wanta86r]

32:1 should be ok but id shy away from castrol oils they produce alot of carbon,i burn yamalube which isnt to bad but the best is amsoil.[/QUOTE]

the oil is castor 927, not castrol, and that is the kind that esr reccommended to me