I’m thinking the gears are there to improve acceleration, not range, and to make bikers feel more ‘at home’.
I guess if they had some high minimum required acceleration, then gears would be required.
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It looks like you answered your own question: Gearing for an electric vehicle could be for speeding up the motor into its efficiency sweet spot, rather than slowing it down into its efficiency sweet spot like gearing does for an internal combustion engine.
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They sell electronics similar to the Tesla motor controller approach for kids ride on toys! Just not as powerful. Rather than build my own, I was looking to buy the electronics before I decided to just upgrade my son to a real machine. Smaller version of adult ATV and has all of the fancy control electronics. You can even buy the motor controller hardware to make your own electric car right off the internet for relatively cheap money. This stuff has been around a long time and not all that expensive to produce. I’m betting way cheaper than a gearbox but I haven’t done any cost analysis, just going off years of experience…
A former colleague of mine, a geneticist by trade, converted a Volkswagen Cabrio into an electric car using lead-acid deep cycle batteries. I’d like to do the same with an antique Beetle, but I probably never will. These guys make such conversions look easy:
Big current controllers… 900 amp/96 volt DC to variable AC drives for forklifts have been around for 20 years or so. Sure the voltage is 1/4 of a Tesla or a Bolt (400V) but a Beetle or old Fiat or MG Midget could use these for a fun conversion - gearbox or no!
Tesla did that with their very first car, the Roadster. It had a 2 speed gearbox. It gave them LOTS of warranty problems. They dropped it and went to a single speed drive. Good acceleration and high top speed are marketing features for a sports car. A motorcycle would be similar. A variable speed drive and AC motor has a wide operating range but a low gear could give some serious acceleration from a dead stop while still allowing an advertise-able top speed.
Current Teslas don’t seem to have any issues with serious acceleration from a stop. And no one seems to care what their top speed is. I don’t remember seeing any reviews that made a big deal over a Model X’s top speed. Anything beyond about 100 mph seems a little silly for a road car that will never see a track day.
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Tesla toyed with the idea of a 2 speed transmission for the original roadster and couldn’t make it work. But they can rely on marketing to tell you that electric cars do not need multi speed transmissions. BMW i8 and the Porsche Taycan both have a 2 speed box. Formula E can have as many as 5 speeds.
As the motor turns, it generates a voltage that counters the source voltage. This is known as back emf and it explains why the motor efficiency increases at high rpm. At low rpm with nearly zero back emf, there’s s high voltage applied to the low resistance winding. While the high current gives you a large amount of torque, it also generates a huge amount of wasted heat. In a home with a old refrigerator, all the lights in the house dim as the compressor kicks in. At low compressor speed, much of the current flows through the compressor motors winding instead of the lights until the compressor gains speed.
You want to have the motor spin up and generate a counter voltage ASAP. In this condition, the winding sees a low amount of total voltage thus generates a small amount of wasted heat. By using a multi speed transmission, you rely on torque multiplication rather than inefficient high current to accelerate. It also limits the amount of time the motor would operate in the low efficiency range.
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I rarely see motorcycles going less than 80 on the highway.
I rarely see cars going less than 80 either! 
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Whatever speed the cars are doing, the cycles are faster - much faster. I think the motorcyclists are avoiding cars as best they can.
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So, you drive the 275 mile long (Tampa to Miami), Tamiami Trail, too, eh?
It’s near me and I’m pretty sure near you. Drivers haul axx on that highway, often faster than on I-75.
Not too long ago, that guy that left “the trail” was doing over a 100 mph when he left the roadway, crossed lots of (Sarasota/Bradenton) SRQ International Airport property, through the fencing, and crashed through the side of the terminal building where passengers congregate. His car finally came to rest against a rental car counter inside, damaging the counter.
It’s like a race track at normal rush hour times and I’ve seen motorcycles going flat-out there. Crazy.
CSA
Tamiami Trail is just too crowded in the Fort Myers/Lee county area for that much speed.
In fact, during season, the opposite is true. 35 mph in a 45 or 55 zone with people in the left lane wobbling their head side to side looking for whatever shop they are trying to find. And of course diving across 4 lanes making a right turn from the left lane. A bit like Dodge-em.
The highway is another matter. 80 is the standard speed (on a 70 limit) with some blasting by at 100. Actually 95 on the eat coast seems to have more speeders but I don’t spend much time there.
Doesn’t that red, white, and blue sign with 95 on it denote the speed limit?
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Duh! 
Everybody knows that’s it! 
CSA
THAT is my chuckle for the afternoon! 
There’s an old Moms Mabley joke about that. Cliff notes:
Got a ticket for doing 66 on Route 66. Mistook the route sign for speed limit.
Good thing I wasn’t on 95!
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Can you see the traffic jam’s in Florida if people took the route sign’s on I 4 and I10 for the speed.
That’s it? Want another one?
https://www.bing.com/videos/search?q=blonde+to+sydney+funny+video&docid=607996678224413786&mid=F855BA068F19DA3854F3F855BA068F19DA3854F3&view=detail&FORM=VIRE
“ba-dum-TSH”
CSA
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That needs a rim-shot at the end…
I put one on there! Did you get a chuckle?
CSA
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