How bad is my spark plug? Am i running lean?

[Htown-enduro]

Took my DR for a 2 hour ride and waiteda few hours and pulled the plug. The tip looks white but everything else looks black. Does this mean the bike is overheating and/or running lean?

[Htown-enduro]

Heres a picture of it

[robausdemore]

Is the end white or brown? It's hard to see in the picture.

[Htown-enduro]

Is the end white or brown? It's hard to see in the picture.

Its white. The previous owner did the airbox mod, put a pumper carb on, and has a DG exhaust on it. So i put tape over a few of the holes on the airbox that he drilled to try and richen the mix. But the bike ran like crap and bogged out. It needs every hole the guy drilled in order to keep it running correctly. So it seems like its just lean enough to run good (what you want) but the white plug confuses me. I dont want to overheat or blow the top end

[adambolding]

Looks rich on bottom and touch lean on top.Maybe drop needle a notch and go up one on main jet.

[adambolding]

You want a chocolate or gray tip on your plug.

[davidhar]

You can't ride around for two hours and get one fcuking bit of info off the plug. Plug reading only works with a plug chop at one throttle position - put in brand new plug, hold at half throttle with load, kill it while still at speed, stop pull plug. Despite what the guy above me said, different parts of the ceramic insulator do not read different parts of the carb tuning. There is no spot to read for the main jet with another part of the plug right next to it that dies not see the main but does see the needle.

[Htown-enduro]

You can't ride around for two hours and get one fcuking bit of info off the plug. Plug reading only works with a plug chop at one throttle position - put in brand new plug, hold at half throttle with load, kill it while still at speed, stop pull plug. Despite what the guy above me said, different parts of the ceramic insulator do not read different parts of the carb tuning. There is no spot to read for the main jet with another part of the plug right next to it that dies not see the main but does see the needle.

Sorry i failed to tell you all this but the whole plug has over 10 hours on it. 2 hours is just the time i had rode that day before i pulled it

[adambolding]

Do you think the black soot on the outer edge of plug came from when you tapped off part of air box and it ran rich? It could be as simple as going up on main jet size.

[Htown-enduro]

Do you think the black soot on the outer edge of plug came from when you tapped off part of air box and it ran rich? It could be as simple as going up on main jet size.

No i took this picture before i did the tape test

[adambolding]

Something else i found on one of my old bikes is the oring in the air/fuel screw was rotten.Just remember to screw in and count how many turns til it seats before you take it out so you can put back in.I have a lot of jets and will give you one if you want to go up size on main and drop needle down one which means put clip one notch above where it's at.Doing that would lean the lower rpms and the bigger jet would fatten upper rpms which is what I think is your problem.Im sure there's some keyboard warriors on here that might shoot me down but that's my opinion on your problems.

[Htown-enduro]

Something else i found on one of my old bikes is the oring in the air/fuel screw was rotten.Just remember to screw in and count how many turns til it seats before you take it out so you can put back in.I have a lot of jets and will give you one if you want to go up size on main and drop needle down one which means put clip one notch above where it's at.Doing that would lean the lower rpms and the bigger jet would fatten upper rpms which is what I think is your problem.Im sure there's some keyboard warriors on here that might shoot me down but that's my opinion on your problems.

Ok i get what you are saying. But please exuse me if i sound ignorant right here, but doesnt the DR 350 use a butterfly throttle instead of a needle type?

[adambolding]

The cv carbs has a butterfly for the vacuum that operates the slide and the dirt carb doesn't.

[adambolding]

All street legal bikes that are still carbureted have cv carb. The butterfly is for the vacuum circuit that operates the slide with a diaphragm. They are all junk but if tuned right they will do the job.

[Steve Sturdevant]

What were the conditions when you stopped the engine before you looked at that plug.  Throttle position, load, RPM?