Loss of Power, Stall After Bumps

[Vision]

That's interesting Ruffus. This is the coil, maybe it's running the plug hot.

https://www.amazon.com/Performance-Ignition-Scooters-Sandrail-Coolster/dp/B00N2HG57K

[Ruffus]

Dunno, to be honest. It's guesswork like a lot with this, our scoots. But could be a nail on this iridium coffin.

[sparko]

Maybe it's the Shell Rotella T6 synthetic 5W-40 diesel engine oil.

a friend is a former Toro commercial lawn mower sales rep. He says nearly everyone uses the wrong kind of engine oil in their mowers. This is an air cooled engine 4 stroke not a diesel. and if your cap is loose like you mentioned that would be another concern. Doubt the plug is the problem. Small air cooled engines need different additives than a diesel engine does. My mp3 400 revs quite high, over 5000 rpm and needs a certain kind of oil. Dont' see why the kymco 125 wouldn't do better with motorcycle oil. or something better suited than diesel oil. Diesels don't rev very high.

[Vision]

T6 is popular with scooter, ATV, small engine owners so I started using it about 10 years ago.

[sparko]

T6 is popular with scooter, ATV, small engine owners so I started using it about 10 years ago.

diesel engines have no spark plug so maybe oil designed generally for diesel is part of the problem. I am a late comer to this area of engine maintenance so I will add a link to what I am currently reading for anyone who is interested. I am sure many of you are already aware of this material.

https://www.mototribology.com/articles/jaso-explained-part-1

[Stig / Major Tom]

The evidence from the many and long-time Rotella users here, strongly suggests that the Rotella is not causing his problem.

Stig