Controllers for brushed motors: Brushed motors are also used in e-bikes but are becoming less common due to their intrinsic lower efficiency. Controllers for brushed motors however are much simpler and cheaper due to the fact they don't require hall sensor feedback and are typically designed to be open-loop controllers. Some controllers can handle multiple voltages.
At $799, it is one of the most affordable full-size folding electric bicycles on the market. There are cheaper folding e-bikes out there, but they generally have much smaller wheels and lower top speeds. With 16″ wheels and a max speed of 32 km/h (20 mph), the Shift S1 combines the specs of higher priced e-bikes with the affordability of a budget folder.
So first off, it isn’t fair to compare the power of a Chinese rear hub motor watt for watt with a 250W Bosch or Brose or even a Shimano or Yamaha mid-drive motor. There just isn’t even close to the amount of torque or power on a per watt basis and that’s before we get to controllers. However, comparing the Rattan’s 350W motor to the Ancheer’s 250W motor seems more proportionally correct. Where as I could make it about a third of the way up my driveway hill from a cold start on Ancheer throttle, I made it about 2/3rds of the way with the Rattan, or another 100 feet. On a flat surface, again with throttle only, I hit 20 mph in about 10 seconds with the Rattan. It takes me another 5+ seconds to get there on the Ancheer. One note, the battery gauge does bounce around a bit depending on how much it is working. At full throttle you might lose a bar or 2 only to get it back once you coast.
The other motor is the G311, a front equivalent to the wonderfully silent G310 rear motors we introduced late last year. This motor will be replacing the G01 hub for our front mini geared kits. It's a tad lighter (2.3kg), much quieter (spiral gears!), but still has the features from the G01 that we loved. That means a side cable exit, ISO disk rotor compatibility, and 10mm round axle.

Hmm, that’s unfortunate. I actually have a doctors note that I carry along which recommends the use of an assisted bicycle. I ride thoughtfully and have never been asked to show it. I cannot comment on the federal parks, perhaps they are not aware of the federal law classifying electric assist bikes that perform at or below 20 mph and 750 watts as bicycles. Having a note and this information would be a good response if you were questioned.
Federal law defines the limits of a low speed electric bike, equating it to a bicycle, and bypassing the definition of a motor vehicle only “For purposes of motor vehicle safety standards…” which means that the manufacturers of these bicycles don’t have to meet federal equipment requirements, and are instead governed by the manufacturing requirements of the Consumer Product Safety Act. There is no mention of exemption from other federal, state, and local traffic laws, or exemption from the definition of a motor vehicle for other purposes.3 This means the law applies to the manufacturer’s product and sale, avoiding federal safety requirements applying to a motor vehicle such as brake lights, turn signals and braking specifications. The goal of the law was to give businesses a legal framework to define and sell low speed electric bikes without the more stringent Federal classification of a motor vehicle. Ebikes that meet the criteria are considered a “bicycle”, do not meet the definition of a motor vehicle, and will be regulated by the Consumer Product Safety Commission. The law also grants the commission authority to add safety requirements to this product. The Federal law supersedes all state laws that equate bicycles to ebikes where the state law is more stringent (lower limits) on power and speed. 

If you have dynamo-powered bicycle lights, you already own an electric-powered bicycle! Consider: as you pump your legs up and down on the pedals, you make the wheels rotate. A small dynamo (generator) mounted on the rear wheel produces a tiny current of electricity that keeps your back safety lamp lit in the dark. Now suppose you could run this process backward. What if you removed the lamp and replaced it with a large battery. The battery would kick out a steady electric current, driving the dynamo in reverse so that it spun around like an electric motor. As the dynamo/motor turned, it would rotate the tire and make the bike go along without any help from your pedaling. Hey presto: an electric bike! It may sound a bit far-fetched, but this is more or less exactly how electric bikes work.

Cargo bikes and city bikes are common in the e-bike space, but until recently we haven’t seen that many performance road bikes. The Giant Road E+1 is a pedal-assist performance road bike that’s made for more than just commuting; the powerful motor can crank you up to 28 mph very quickly on the highest setting so you can rip the flats, join your local group ride, or blast through the mountains with far less effort than a traditional road bike. It won’t feel like a 16-pound race bike when you lean it into high-speed turns, but the endurance-oriented geometry allows for an aggressive position on the bike and keeps it nimble and agile at high speed.

Perhaps the cleverest thing of all about the Electric Brompton is that despite all the extra stuff, it folds up exactly the same as the non-powered variety. It's so simple, and unlike certain folding bikes we could mention, what you're left with is a genuinely small thing, rather than something that's about the size of a bike with the front wheel taken off.