[xpd153]

I switched to 17/45 sprocket config. And did not find any problem.
When Honda made RC27 in 1987, motorcycles' legal upper speed limit in Japan was 80km/H.

So basically genuine sprocket config(final reduction ratio) is too high.(It means too low geared).
As I mentioned in other thread, driven sprocket(rear) has a few selection. But drive sprocket(front) has wider selection.

So I can recommend replacing drive sprocket if your country's regulation for upper speed limit is more than 100km/H.

[robvangulik]

With that ratio the acceleration will be a bit less, and you won't get to top revs in top gear, but I don't think you'll go there very often.
I would have gone for a 16 teeth, just to try first.
Sorry, I have that program only in German language, but the numbers are understandable, I presume