If the solenoid is removed then jetting the bike for low down power becomes a little more critical, although it can be done.

The hoses that originally came from the solenoid to the carbs will have to be 'jetted' to regulate the air supplied to the emulsion tubes, or you'll suffer real lean conditions.

One of our bikes is running sans solenoid and I've stuffed a couple of #170 main jets into the hoses with #185 mains, stock 21 needles and #40 pilots. Runs a little rich at the top (#180's would probably be better) and can load up in traffic, but when the thing's on the open road it flies and is as smooth as ya like.

On an MC18 300 I built we tried for a laugh a similar set up. It worked fine, but this time with #142's stuffed in the hoses. I was trying to get rid of a dead spot down real low (1,500~2,000 rpm). It didn't work, but it didn't have any adverse effects on the top end rush.