Plug still dry black (wtf?)

[MtnEX]

OK, I rebuilt my carb... it's good.

I also rejetted.

I went with the 42 pilot everyone recommends.

I dropped the main from a 155 to a 152.

After just general riding today on a fresh NGK, the plug is still dry black all over.

I just don't quite get it. I have a full exhaust and a K&N until the UNI comes... air box lid on.

I will try with it off tomorrow, but I don't think it is going to make that much of a difference.

I don't have a 150 main here... but I can throw in a 148 out of the Moose carb kit.


I don't know what to think anymore.
I would think the stock 148 would be on the lean side for stock emissions?

I am at 1250 ft riding right now.

HELP!

[Miami_Vice454]

well for starters, are you doing the plug chop correctly? you have to get in like 2nd or 3rd gear and hold pretty much WOT for a couple seconds and then pull in the clutch and hit the kill switch at the same time. then pull the plug.

[bkelley]

I thought you wanted to get into 5th and hold it between 2/3 and full throttle (without it bouncing off the rev limit) for a few seconds or so (1/4 mile or whatever) then pull the clutch and kill it?

[MtnEX]

No... I am not doing plug chops on the thing.

It was just being ridden around some to see if it was close enough to get that into it.

Ultimately if you are still rich on one of the circuits, you are going to have a blackened plug... unless the main is perfect and you just did a good long chop.

I have a fresh plug in it to check the pilot tomorrow. And another to check the main after that... and maybe one to check the needle as well.

This jetting... I would think... ought to be spot on?


Lid on, K&N, Yoshi full, 1250 ft elevation...

[Wheelie]

The 42 pilot is way too much w/ the lid on. Go with a 38 or 40.

[MtnEX]

Originally posted by Wheelie
The 42 pilot is way too much w/ the lid on. Go with a 38 or 40.

Thanks...

I'll take the lid off before I start this today then.
I have no problem at all picking up a 40 if I need it.
38 seems too finicky on starting and warming up.

[clemsonteg]

What kind of jets are you using. Remember that unless they are the keihn jets then they may not carry the same numbering system. Dynojets read lower for the same size jet. For example they recommend a 146 with a slip on and air filter. I also know some places put their name on dynojet kits and market it as their own like fmf.

[MtnEX]

Originally posted by clemsonteg
What kind of jets are you using. Remember that unless they are the keihn jets then they may not carry the same numbering system. Dynojets read lower for the same size jet. For example they recommend a 146 with a slip on and air filter. I also know some places put their name on dynojet kits and market it as their own like fmf.

Well, I was going to buy ProX from RMATV but my Honda dealer sold me on the RD Precision... which I was not sure of before... but they use them with great success I'm told.

Both have the same numbering system as OEM.

[MtnEX]

OK, so I put in a Champion PowerSports plug... no more NGK's left in my stash.

I started out with the airbox lid off...

I like the way it starts with the 42 pilot.

I let it warm up well on a fresh plug and messed with the fuel screw. Turning it in, it dies before it gets all the way in. Backing it out, it lifts the RPM... but then I can keep backing out without much change.

I gave up and set it at 2 1/2 turns out.

I pulled the plug after all that and it was real clean. I didn't see anything to scare me. It was just almost unused looking still.


So I put the same plug back in and ran it around on the needle a bit... tried to hold one throttle position turning laps around the field.

Let it cool and pulled the plug.

Center electrode and ground strap look good. Center porcelain looks OK... white and brown.

Base ring at the bottom of the threads is solid black. Dry black, but not really powdery looking. More almost like painted flat/satin black.


I will warm it up on this plug and then install another for a full throttle run tomorrow.


Should I open the top and change the needle clip one position before doing any more?