Belly pan/fairing lowers reducing drag?

Just curious does fitting a belly pan or full fairing lowers to a curvy s decrease it's drag coefficient substantially enough to overcome the extra weight effect on acceleration?

And is there any improvement in top speed?

Just curious as have always fancied a belly pan but thought the cash would be better spent on springs, fork oil, petrol and track day entries!

[northwind]

The weight's pretty trivial, in the grand scheme of a 170+kg bike with a rider on... But aerodynamics... I doubt there's a single lower fairing set that's seen the inside of a wind tunnel, so they could be doing anything really. Smoothing the sides of the bike would cut drag, in general, but then the rear edge of the fairing could create it, and you could still have airflow underneath which would mean you'd have about as much drag as usual from the engine, frame etc, plus more from the frame.

In short- don't know Now a full fairing, race fairing etc, that could be a different story as they tend to be simpler and tighter fitting that lowers. The manufacturers probably won't have wind tunnelled them but they tend to be based on bikes that have probably been extensively tested.

the result of the new GSXR1000 with build in blinkers was 3% less resistance...

[northwind]

Yup, but that was entirely removing a source of drag... With fitting lowers, you're adding a source of drag and hoping it reduces the existing drag by more.

Most of a bike's aerodynamic inefficiency comes from the humungous hole they tear in the air- you can't effectively streamline the tail, not on a road bike. I read once that for all the talk of the Busa's slipperiness, it's the massive seat hump that makes most of the difference, the frontal drag coefficient isn't much different from a GSXR SRAD. And I gather that MotoGP bikes tend to be designed for downforce, not for reduction of drag, for the same reason- no point in making the front uber-slippy when the rear's still like a brick.