I see several on my commute, the eBike version anyways, no peddling, just cruising up hill. Don't see the point, might as well get a moped.
I dont know, just because you don’t see the point, it doesn’t mean there isn’t one, and if it gets some poor soul out on a bicycle who couldn’t otherwise manage it I’m all for it. Easily accessible ebikes are getting more people onto bicycles than ever, and the legal ones are strictly pedal assist which means they still have to do some of the work. That was the intent of the one I built, but in the end the power differential between the motor and the wheezy old knacker in the saddle was so great that the assist was about as relevant as assisting your lawnmower with a pair of nail scissors.
My own objective was to cover the 20miles between my house and my office at a decent pace, without recourse to thousands of pounds of moped, insurance, tax, fuel, safety gear and all the other minutiae that come with motor vehicles. I’d also like to arrive not needing a shower and a change of wardrobe, and not die doing it due to the ineptitude of some daft bus driver or uberist.
I’d cycled to work a number of times in the past, but it was hellishly dangerous for the above reasons. This I think is the main obstacle to widespread cycling (along with headwinds, hills and drizzle). I then found that I could cover all but the first and last mile of my trip on canal and river towpaths. Lovely scenery, wildlife, fresh air, a canal side pub halfway home and no Uber’s. Cycling nirvana, except for swapping smooth-ish tarmac for lots and lots of wheel grabbing, speed sapping gravel which rather increased the workload and increased the time taken to get there, and when combined with a headwind had me arriving at work in need of a sauna, a mid strength beer and a good lie down.
I then built the electric bike using all sorts of odds and ends from all over the world. Now I could get to work faster, enjoy the scenery and pay almost nothing for the privilege. I could go places mopeds couldn’t, cause zero offence, and arrive at work fresh as a daisy...
Like all home built contraptions there were downsides. As well as greatly overestimating the battery requirements I hadn’t got my sums right when setting the gearing for the jack shaft, so peak motor efficiency didn’t come matched to ideal pedalling cadence. Real Lycra clad roadies like a cadence around 90rpm I’m told. To keep up with this thing you need about 150rpm. Result? Over 15mph you can’t keep up with it. Your feet would need to be a blur the likes of Roadrunner or Billy Whizz to add any meaningful torque. It’s not a drawback for the terminally lazy as you can just stop pedalling and let the bike do the work. The pedals are connected to the drivetrain via a one way clutch (a BMX freewheel in the centre of the crankset), but you can’t really call it “pedal assist” above 15mph. It really does become a moped. The notion of being sweat free after the hour or so in the saddle was also miscalculated since despite not pedalling, you still had to work bloody hard to wrestle it through the bends, locks, bridges and underpasses of inner city canals. At top speed on gravel it was like wrestling a wild animal.
The other drawback was the durability of bicycle chain when exposed to the equivalent of 4 jacked up Lance Armstrongs. It had a habit of snapping chains, which while easily repairable, did rather spoil the journey.
All in all though, my first homemade foray into EV’s was a great eye opener
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