air v's water cooled

[VNA]

Ah yes, the C90. Cockroach of the two wheeled world. I suspect they would survive a nuclear attack.

Cockroach!?  The world's best selling motorcycle.  Hasn't everybody got one?

The main reasons for the motorcycle manufacturers using water cooled engines was to quieten the mechanical noise down to pass noise regs and because the new 'fashion' to enclose bikes in fairings required a need for better cooling (the engine sees less airflow enclosed by a fairing of course) The GPz900R is a good example of this, although they didn't really get it quite right and it did tend to overheat rather a lot.
Manufacturers would love to make more aircooled bikes because they are cheaper to produce.

Don't think noise regs threatened air cooled engines till well after everybody had pretty much gone water cooled.  And umm big air cooled bikes are still on sale. 

It's BHP init?  More BHP means more heat, I guess you could make the engines bigger with bigger fins but that's pointless, so it's water cooling init, only way to get rid of all that heat.  More BHP = more sales.

Cheaper, is there really much if anything in it? 

Air cooled always looks better, well unless it's a kettle.