So, just arrived at my home island and I'll be staying for a couple of weeks and will try to finish the bike...
I've been searching for some more info on sparkplug reading and the most similiar picture I've found was this #4 on this page: Spark Plugs
The sparkplugs I use are the XT's stock ones! the NGK DPR8EA-9!
All get like that after less than 30miles...
(Very similar! just not as many deposits as on that image.)
I've also got two DPR8EIX-9 (iridium in my garage) that I've tried and they also got the same colors...
The thing is, I didn't set the gaps on those sparkplugs!
Now....By reading the description it says my sparkplug is Too Cold!
My problems I believe are: incorrect sparkplug gap and too much fuel and most likely a little bad sync between both carbs!
Today I've adjusted the gap! It was a bit over 1mm... yes, too much!
I've set it to 0.7mm as it says on the NGK website it should be between 0.6 and 0.9mm.
This should solve the gap part!
As for the overrich condition I'll be ordering a few lower mainjets in 2.5 steps which should help fine tune my carb.
Plus, the bike pops a bit on decel and has a small hesitation at constant throttle which I've been dialing in.
There are no air leaks!
Jets are: 145L 150R, #25 pilots, needle clips in 2nd groove from the top. as for the fuel screws I don't remember how many turns in/out...
Carb is a dual BST33mm from a 2002 raptor660.
bike is a 1990 XT600E
Other mods: KEDO (devil) downpipes, WR450 exhaust, K&N RU4710 air filter with pre-filter water repellent sleeve, Custom made fiberglass open airbox.
One other thing, Don't have a rear tire right now lol
So no stop and go sparkplug, throttle position + engine cut-off readings.
One more thing, should I put the same mainjets on both carbs?
I don't really know the engine need for fuel from low-mid-high rpms...
If for mid-high rpms the 2nd carb is fully opened, a slighter higher fuel output sounds "obvious" I guess...