Badass e-Bike Speed Tuning Dongle

General Discussion about electric bicycles.
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Re: Badass e-Bike Speed Tuning Dongle

Post by Voltron » Jan 10, 2018 4:19 pm

Nice circling back :wink:

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Re: Badass e-Bike Speed Tuning Dongle

Post by LockH » Jan 10, 2018 5:14 pm

wturber wrote:
Jan 10, 2018 3:50 pm
I like the idea of standardizing these rules across the various states - if the rules are good, sensible and an improvement on what is in place.
:) See also the "United Nations"... and their "common law" for the "electric pedal-assisted cycle" - "EPAC"...

`Cept ya can't trust lawyers not to build-in more work for themselves. :wink: Ebikers maybe have at least two "problems"... The "Roman approach" - to "divide and conquer" - and "vested interests". Folks that are "happy with things as they are"... as long as it doesn't negatively affect THEIR "bottom line". :wink: But I count on the ES Nation to develop the "work around". :lol:
ES changed my life (for the waaaaay better).

Eff. June, 2014 Phoenix Ebike Promotions

(Current ride? High speed lawn chair.) ... =3&t=57408

Phoenix Ebike Promotions conversion kit (work in progress. More drink holders, etc etc) ... 15&t=60564

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Re: Badass e-Bike Speed Tuning Dongle

Post by teklektik » Jan 10, 2018 6:15 pm

The Federal CPSC regulation is for a motor producing 750W. This only pertains to sale of new bikes, not their use which is controlled exclusively by the States. Any blather about federal power or speed limits for ebike road use is nonsense - that is simply outside Federal purview.

State Traffic statutes (pertaining to use not sale) that specify 28mph are recognizing that 750W is enough to propel an 'average' bike+rider to about 27mph. Adding in a modest sustainable 70W of pedal effort yields 820W which is enough to push the bike to 28mph. See the simulator or any bike calculator.

As odd as the number may seem, it's not an unreasonable maximum speed estimate in consideration of the Federal 750W power limit on what can be legally sold. This tacitly assumes that any artificial speed limiting to meet the Federal 20mph motor-only limit for sale has been deactivated so the bike is operating essentially to its physical limit with sustainable help from a pedaling rider. This modification is not illegal in the US once the bike has been sold because the CPSC Federal mandate only addresses product manufacture and first sale (e.g. once you buy a mattress you can tear that scary CPSC tag off and even legally sell it without the tag - the tag had legal significance only at time of manufacture and when sold as new).

This 28mph speed limit is pushed by manufacturers because it more accurately reflects what 750W of power can do rather than focusing on the artificially low safety limit of 20mph specified by the CPSC whose mandate is specifically product safety and who tried to keep performance commensurate with their view of a safe 'low speed electric bicycle'. This 28mph approach is more defensible for the manufacturers since it doesn't challenge the hard limit of 750W (1hp), but goes after the more arbitrary interpretation of 'safety' (20mph). It's also attractive to States looking to define legal USE because it accounts for operator pedaling and goes to easy enforcement criteria - the cops don't need a dyno in the trunk - if you're riding at 35mph, you're in violation by an easily measurable 28mph metric.

By the same token, the CA classification of 28mph bikes (type-3) does recognize that although this might be achievable with a legally purchased bike, operating it at the motor limit makes it somewhat 'un-bike-like' and so they are not allowed on class 1 bike paths.

Anyhow, the 28mph idea is not as loopy as it sounds and was chosen to let folks realize the limits of what the Fed allows to be sold as an ebike while completely sidestepping the whole Federal CSPC/DOT territorial legal war.
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