Scooterotica

I can never remember which way around it goes. So, the 5899 atomiser as fitted to the SH carbs. On a scale of 1 - 5, which is richer?

I was told 1,

Hmmm...... I wonder what they would have used that in? Just discovered I've got one. No pun intended.

So, the larger holes in the number 4 atomiser would presumably be to weaken the mixture?

That's certainly the way it appears with the mixer tubes in the SI carbs. More / bigger holes = leaner

I am under the impression that 1 is rich 5 is weak if youthink about were the atomiser is and were air gets fed from into those top holes it comes from the bottom brass venturi on the front of the carb so the more air that flows through those holes either becouse the holes are bigger or there are more holes the weaker the mixture but this may be able to be compansated with a larger mainjet but what effect this wil have through the range I dont know

That's a good explanation Steve. I imagine then that you could weaken or rich the mixture in the middle range with the top of the range being governed by the main jet? Probably more use on mid sized engines. With a 200 you wouldn't seem to have that much lee-way.

Some good info about carb in general and atomisers in this thread -

http://scooterotica.org/forum/viewtopic.php?f=8&t=33015