Originally Posted by GearNut
1. Never use outboard engine pre-mix oil. Outboard engines are water cooled via the cold lake or ocean water that is pumped through them and operate at much cooler temperatures than air cooled engines and have far different thermal protection needs.
The universal oil you are using now is much better suited for your engine.
2. I have one very big issue with that tutorial video by BikeBerry. When doing a plug chop the engine needs to be under a load, ride the bike!
Just revving the engine at a standstill will not provide the real world conditions that are needed to properly color the spark plug. The engine is not doing any work while at a standstill, just merrily spinning faster.
Ride the bike for 1/2 mile or so holding the throttle at the position in question then at the same time pull in the clutch lever and hold the kill switch until the engine comes to a complete stop. Do not let the engine idle or run what so ever. Doing so will ruin the color print on the spark plug. Let the engine cool for 20 minutes or more before removing the spark plug. If you remove the spark plug from a hot engine you risk damaging the threads inside the soft aluminum cylinder head.
3. Most engines run a little rich at idle speeds. If you are checking the color of your spark plug based on just idle speeds expect it to be darker than desired.
It is supposed to be a cardboard brown to milk chocolate brown color, not black and oily.
Thanks for the reply! I'll do the plug chop straight away. Should I replace the old spark plug with a new one or is it ok to keep the current NGK B6HS in there.
Also does it sound like the motor is 4 stroking? I'm new to this so I can't really tell.