2 strokes, plug ratings, help!

[B0000M]

As above less oil will mean more fuel passes through the jets faster, making the mixture (fuel, air) richer. This will only make your situation worse.
Put the stock plug in, I would use Motul 800 at 32-1 on a 125 and check the airscrew setting or take it to someone who knows about jetting. As the weather warms up the bike will run richer, so it maybe jetted for winter and the airscrew adjusted, you will probably need to drop a size on the pilot, needle clip may need to be raised a position and a one size smaller main may need to be fitted.
You will also need a clean filter not over oiled and a freshly packed muffler would not hurt.

Confused now by all the conflicting advice?
Once you know what jets are in the carb you might want to call Triple X Moto as I'm sure they will have jetted a few 125's for some of their customers and can send you the jets you need. You'll be wasting your time just changing plugs as they are usually the last reason a bike fouls, as is the slow speed the rider rides at. A correctly jetted two stroke will not foul plugs.

everything he said.

[Dingledoo]

As above less oil will mean more fuel passes through the jets faster, making the mixture (fuel, air) richer. This will only make your situation worse.
Put the stock plug in, I would use Motul 800 at 32-1 on a 125 and check the airscrew setting or take it to someone who knows about jetting. As the weather warms up the bike will run richer, so it maybe jetted for winter and the airscrew adjusted, you will probably need to drop a size on the pilot, needle clip may need to be raised a position and a one size smaller main may need to be fitted.
You will also need a clean filter not over oiled and a freshly packed muffler would not hurt.

Confused now by all the conflicting advice?
Once you know what jets are in the carb you might want to call Triple X Moto as I'm sure they will have jetted a few 125's for some of their customers and can send you the jets you need. You'll be wasting your time just changing plugs as they are usually the last reason a bike fouls, as is the slow speed the rider rides at. A correctly jetted two stroke will not foul plugs.

Thank you - greatly appreciate all your advice, going to check the jets. Please excuse my ignorance: what is a freshly packed muffler and how do I get one?

[vr4king]

Go to your local bike shop and ask then to sell you some 2 stroke exhuast packing and ask them how its done

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