Alright. Let's get controversial here.

I think our machine performance exactly perfect with shorter gearing. I just did a chain conversion, with a 15t front and 48 rear, giving a ratio of roughly 3.2 over the stock 2.9-3.0.

I can't tell you how good it feels..... My God. I couldn't imagine going for taller gearing. It's not a highway rider in my book, it wants to rip. And rip it does

. https://photos.app.goo.gl/DHneBZTcKT7Sw1eb6

Brap, Brap, Brap, Brap, Brapppppppppp!  I bet it is pretty fun running it up and down the gearbox!  Will the engine braking take you from 60-0 in 5th in 120 feet without touching the brake? (Joking exaggeration)

Can you still hit 75mph?  Hey, you might even be able to hit the redline in 5th with that setup!  I wonder how much gas mileage is impacted.

I think you nailed it with “controversial”.  The taller gear camp wanting lower RPMs at highway speed in top gear.

Nice job on the conversion!  If you decide you want to tinker with it, you have fairly simple swap options.

Unrelated - how’s the clutch holding up?  What does it think about the chain/sprocket conversion?

Here’s a pretty cool sprocket calculator that shows the changes in torque and top speed.  There are more elaborate calculators, but I like this one for simplicity.

https://sprocketcalculator.com/

The stock belt drive final drive is 68T/23T = 2.96 (as you vaguely noted).

I figured you could still hit 75 (kinda joking).  Top speed for stock is pretty well tested around 93-95.  I’ve had the S40s I’ve owned up to about 85.  That was fast enough before thing’s seemingly might want to vibrate apart.  They all still had a little bit left, so 93 seems doable with the right conditions.

Yeah, 4th and 5th is where I’d expect you to notice the most difference.  You actually still have some real torque to use with the lower gearing.  While the calculator suggests about an 8% reduction in top speed with the lower gearing, I doubt it’s that big a reduction since you can probably get higher rpms in 4th and 5th with the lower gearing.  The calculator rather falsely assumes you can hit the redline before lowering the gear ratio.

My stock S40 is always searching for 6th gear!
Cheers!  

Philly likes shorter gearing.

Dave likes taller gearing.

DragBikeMike’s hotrod breaks 5-speed gearboxes.

Zipi is constantly searching for 6th gear (me too).

Suzuki tries to please everyone with the middle of the road.  No one is happy and it gives us a reason to modify.  lol.

I have a squking belt, and the double row ball bearing change already done.
I find the noise is at the expense of my riding pleasure.
So I am thinking about a chain.
Because because I live in an urban area I don't go on the highway much I want to try a lighter transmission given your enthusiastic reaction  

I think I,ll make a chain protector.

Newbie here, trying to nail down some decisions for winter projects for my 2002.

One is about wheels. I have the stock spoked wheels, but the bike also came with a set of GS550 alloys in 16 x 2.5 rear and 19 x 1.85 front. They look good, but there are complications. Brake rotor, tire size on such narrow rims, custom made axle spacers, etc.?

One question was what will the taller rear wheel do to the gearing? The calculator below, which I think I got from another post on this site, has been very helpful for my wheel and tire decisions:

https://www.gearingcommander.com/

Now all I have to do is calculate (interpolate) the gearingcommander results to see if I can figure out from sprocketcalculator (thanks for the link!) what effect my choices have on power and torque.

The clutch that was mentioned have an easier life with shorter gearing. Personally, though, I like loafing engines, not screaming ones. YMMV