In looking for a more powerful e-bike I see a number of adds (especially on Amazon) for dual powered bikes. Are these bikes being made as cheap mopeds or do you even pedal them?
Depends on the bike. Some - particularly the adventure bikes from the hunting bike folks - are pedalable.
I think its a mistake to see a dual-motor bike as a powerhouse. The benefits of 2wd are really achieved thru distributed traction. Done right, the fact you have two motors can be entirely seamless with dual PAS, where the bike just launches with a level of ease and controllability you can never touch with a rear wheel drive no matter how much power you pump into it. It just works better.
Street bikes. Dual hub. I would never do a dual hub again but they were a blast as fast, pedaled pavement commuters. The reason is hubs are great on flat land and I live in hills now. I put about 7000 miles on the orange one which is the only one I still have..
The permanent solution to the limitations of using two hubs is to put a mid drive in the back instead. At that point you have a bike that can go anywhere (deep dry sand) and climb anything without strain. Since that pic was taken I switched to a Box2 XW rear derailleur and a pie plate cassette.
Is it safe to assume there are two batteries that need to be charged?
In years past, yes. In the present day occasionally no. Typically you see standard off the shelf packs used. They may or may not have a single-charge solution built in. Given the varying quality of 'battery blenders' out there, I would not trust that. There are one or two companies that sell a single XL battery that feeds both motors at once, which means it has to have a really hi-cap BMS. They need to be in the 80a-plus continuous output range which you will never find in a generic pack.
Does anyone make one that is as reliable and supported as most of the mainstream bike vendors?
No (provisionally). E-Cells is probably the oldest vendor in this space but given their horrible record for truth-in-advertising, I would not trust them under any circumstances. Generally speaking I have a VERY low opinion of manufactured 2wd ebikes. The only one that has a shot at acceptable reliability/support is Ubco, a New Zealand company that markets their bikes as reliable farm, patrol and military use bikes. But last I saw they didn't have pedals. If they have grafted some on I have to believe they are not meant to truly be used.
For a completely different take, take a look at Christini, who do true AWD and not 2WD. One motor and an ingenious differential between the two wheels so when the back wheel slips, the front wheel takes over. Not the same thing as what you are asking for though. Christini did awd motorcycles first and sold some to the US Air Force for base patrol IIRC.
Store-bought 2wd bikes tend to command a premium price for doing you the favor of a Version 1.000 implementation of 2wd. They often dumb down the functionality, trusting that the noob rider will be so happy with what they get, their lack of experience will mean they never realize what they are missing out on.
Probably Aniioki has done the best implementation of the concept in terms of providing features. Their super duper model is well thought out, but its unique beefed up brake rotors are so unique there's no source for replacement. There is no sign the manufacturer sells them, and if they do, what happens if they run out or go out of business? A 3rd party source for such a basic wear item needs to exist.
2wd is great stuff, and it is well worth having. Especially if you treat its prime benefit as distributed traction, not increased speed (two motors are not faster than just one as the hub motor still has its rpm limit; but 2 motors working as a team do accelerate quite a bit faster, and a front motor completely eliminates all wear that a mid drive visits on the drivetrain).
I like to build top-quality-component ebikes from the frame up. Quite a few of them are dual motor or AWD or 2WD or whatever you want to call them. Why would you build an AWD ebike?
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