Interesting. I looked them up. A number of pros/cons. More cons as they are heavier, more expensive, and difficult to get parts. You've mentioned the pros. The main problem is that they move at a 'steady pace'. You can't downshift on a hill, you can't upshift going downhill ( to go faster). But, they are out there and if you don't need versatility (meaning you only ride them in relatively flat areas all the time, possibly for a commute), they'll do the job nicely. I see e-bikes as good for commuters. We have an increasing number of people commuting to work on bicycles and an e-bike (a.k.a. 'cheater bike') is a great alternative.
The shaft drive bikes are SLIGHTLY heavier. But only a pro biker would take notice.
Plus the frame on mine is aluminum and much lighter than a steel bike so there's that as far as size and weight.
And those are 700 series tires. Not heavy cruiser or off road tires. I've never wished I had those larger heavier tires either.
Shifting is no problem ... up shift, down shift, uphill, downhill. Shift at ANY time to ANY gear ... virtually instantly.
No chain lag, slop and what ever else is encountered chaining and shifting a conventional bike.
Parts? ... had my bike for 20yrs and never needed any drive train parts. None. Not one.
Keep the drive lubed internally with bearing grease and good to go ... for decades+
The effortless smoothness into and out of any gear at any time, lack of required maintenance or periodic adjustments is AWESOME.
No idea of course where you got your information. Mine is from seat on the saddle and hands on the bars.
I read what you typed and thought, he can't be talking about a shaft drive bike. Not the shaft drive I have anyway.
In my experience, I've found no cons ... unless someone thinks the fact you have to pedal it is a con
Not only can you shift at any time, including when standing still.
Gone is the frustration of trying to downshift from a high gear when you bike to the top of a hill.
Just twist and you can go instantly to any gear without even needing to roll.
But also ... due to most bikes not being properly tuned at all times, the overall efficiency in the shaft drive system is better than what most bikers will ever experience with a chain drive.
The most interesting part of riding a shaft drive bike (other than all the attention it gets from people who notice its lack of a chain) is the noise it makes: NONE. The bike is SILENT other than the sound of the tires on the road. When coasting, there is not tick-tick-tick-tick sound of the chain. When you shift, there is no clunk and the chain jumps to the next gear.
Oh and my shaft drive bike weighs 29lbs. Maybe too heavy for some, not me that's for sure.
Lighter than many hybrid, cruiser and some off road bikes but heavier than road bikes. Good ones anyway.
Drive train is enclosed / sealed. I can ride in any kind of filth, condition or environment without worry or extra maintenance. It's a dream.
And no power outlets required. When power goes out or in the boonies, I can still go for endless miles and miles ... and then continue not to worry about an outlet.
The shaft drive on my bike is a Suxxex 3rd generation shaft drive system.
"Our new generation of shaft drive uses bevel gears made of heat treated cromoly, paired with high quality sealed cartridge bearings coupled to a steel shaft rod – all sealed inside a lightweight, durable alloy housing."
I can easily understand why a bike dealer would want nothing to do with, not recommend, or have a shaft drive bicycle.
There is little or nothing to be made off maintenance and adjustments or needed parts after sales, such as with a chain drive multi-speed bike.
My Schwinn 7-speed Cruiser Supreme from the late 90's
I GAVE it away. Guess which bike it couldn't hold a candle to or keep up with not even close?
... the red shaft drive bike ... but I'd kind of worn that Schwinn out. Was hard to keep tuned. I loved it for a time. Cool bike.