I meant to say it was not misfiring due to a lean mix.
anyway, afaik alternate main jets are not available from Honda .. i dunno which older-but-not-too-old Hondas used the Keihin and have similar jets in different sizes.
25: is too much oil for my bike.. smokes and the tail drips oil. I'm using near 32:1.
More oil makes the air:fuel mix leaner .. oil takes the place of gasoline.
Plug gap is near 0.6-0.7mm. (0.025 inch)
Whats up with that rubber intake tube.. im looking at a dismantled swingarm / airbox and that tube is all there is between the filter box and the world outside..
Have you dropped the engine and pulled that rubber intake tube out? It plugs into a smaller roundish cavity off to the side that is not accessable through the filter-slide box opening.