carb tuning advice

[bluesmoke]

After recently rebuilding the engine and carbs I'm having some trouble fine tuning. The carbs are clean and running original spec parts and adjustments. What I'm having trouble with is the transition from idle to low revs. The bike starts, idles nicely.  With the air box removed the slides can be observed. When they start to rise the motor will splutter slightly (miss) until further opening of the throttle and then the splutter disappears and the engine revs cleanly. Out on the highway cruising with the throttle in the same position the bike seems to bog down and will not accelerate unless a lower gear is selected and the revs increase and then the motor will pull away strongly. Weird huh? I have tried raising and lowering needle. Checked float levels. Cleaned and checked everything. Would appreciate any thoughts or feed back.Thanks in advance.

[teezer250]

I would make sure the carbs are clean and set to standard settings,then make sure the air filter is clean and LIGHTLY OILED(too much oil will restrict the air flow,i made that mistake) and the trumpet is in place inside the airbox.
If you are in too high a gear for the revs then the engine will bog down,they are not like a 4 stroke engine which will pull low revs in a high(ish) gear.You need to work the engine through the gears and gear down if necessary to accelerate.

If you are new to 2 stroke engines then you will have to change your riding habits if you have previously rode 4 strokes.

[James P]

After recently rebuilding the engine and carbs...

You don't mention whether the bike was running properly before the rebuild. Whatever the case, could any of the air bleed holes in the atomisers be gummed up? Could any of the reed petals be stuck open?

I gather from your comments that the spluttering starts as soon as the throttle is opened. At what throttle position does the spluttering disappear?

Regards,
James