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'lightest.bike' 1.7kg 1000w mid drive

Why does the torque sensor not work with the dual chain config? It looks like pedal pressure will still deflect the torque sensor arm, will it not?
I was wondering the same thing & it took a while to think it through. In the dual chain config, as soon as the motor applies torque, the top side slack will be gone and the torque sensor will be at zero deflection. The torque sensor seems to act as only a chain tensioner in this situation. Since the motor is now pulling the top of the crank sprocket instead of pulling the wheel sprocket, the torque arm does not feel the difference in force between motor torque and pedal torque.
 
I think rhauff's analysis of the dual chain config is convincingly correct, although I would approach the visualization a bit differently: Note; my approach focusses on pedal torque and ignores motor torque to simplify the analysis.

There are two chainrings, inner and outer, and they are bolted together. The chain on the inner ring goes to the bike's rear wheel. When pedal pressure is applied both rings try to rotate causing the inner chain to go tight and pull on the grounded rear wheel. At the same time the top of the outer chain goes slightly slack. As pedal pressure is increased The inner chain pulls harder on the rear wheel, but the top of the outer chain continues to be slack in the absence of motor torque. The torque sensor arm does not move because there is no tension in the outer chain.

Conclusion: the torque sensor mode does not work with the dual chain config because pedal torque is not detected.
 
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FYI looks like i'm getting that hybrid mount and replacement BB next week.
We'll find out if the drive needs to go back to Italy ( dang ) to fit my recumbent afterwards.
 
Parts arrived!
Well packed and smells fresh from machining 😅

This time we have metal BB cups and 123mm measured width instead of the 135mm w/some kind of plastic cups sent to me in the original kit. I like it.

1709671745960.png

It's pretty tempting to just install this on the 26er for testing purposes and take the easy path :unsure:
 
Ugh, that PIN thing..
I swear i heard somewhere it was 1111 or 1234 somewhere.

Looking forward to the results of your test ride when it happens.

ps do you have a 52v battery and the unit is not programmed for that voltage? i think the difference in cadence is small for that situation but i'm curious on how it works out.
 
Another reason for me to recommend against this company and system for anyone inquiring about it.

I can't imagine relying on any system of any kind that can just randomly require you get an unlock code from the manufacturer.

Any company with such a system *must* be available 24/7 to get back to a customer about this kind of thing in minutes, at most.

Need to ride? Nope, sorry, you'll have to wait (days or longer) till they get back to you...and if they go out of business or stop responding to communications, you get to throw the whole system away and buy something else. :roll:

Yeah...no.

:poop:
 
I once waited 3 years for the start of a race. It was unilaterally decided by the people involved that the idiot who had issued the challenge had to cede defeat since his vehicle was unable to compete.
First chap had a vehicle that he had munged together in his garage and was pushing towards breaking a 10s 1/4 (Ten second quarter mile) he was at 10.8 iirc and really proud of what he had done with a shoestring budget and a lot of sweat equity. Chap 2, swore his vehicle was better in every way and designed to not only handle the hard goal, but addionally was an efficient commute vehicle and could do long track events. Thing is with the NSX he was rolling with, it was entirely feasible he might be the first triple threat car ever brought to the track.

However now on like 5 years later. That NSX has managed to drive itself in and out of the garage like 2/5 times and the rest requires pushing. The potential for the infinite is far outweighed by the actual odds of success.

ANY vehicle that has an anti theft solution (btw, there is no anti-theft in the world that works, it is all an impediment to everyone except the honest folks) that causes more issues for the legal owners than it ever would for a thief is the product of a flawed mind.

And for the record. Chap #1..... yeah, certified at a consistent 7.7s 1/4 out of a 1970s era Datsun... He also drives the car ever weekend to just have fun.

The reason for the lengthy story is you have Amber who has created success out of things that astonish me. And uses the pile of discordant unusual parts as a daily commuter. Vs what is looking like it will be an awesome ride.. if it ever works.

I think the drive solution you are using is an amazing option. But one better suited to corporate thinking. Meaning it would be good if it was designed and eventually produced a working proto-type where the goal was a production bike. You have the goal of a never ending proto-type. This requires you have complete control over every aspect of your build because you are changing things daily. As opposed to changes made during concept, and applied either never, or not until you are at "solving manufacturing issues" stage of events.
 
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