flat tire said:
Yeah it would be badass and I would buy it immediately but on the other hand it's a fairly marginal improvement from something like astro the major issue is still the reduction. Where are the good, compact reduction units?? You can't even buy a Tangent now cuz they've decided theirs sucks and needs reengineering.
It seemed like an amazing idea at the time, until i heard the sound that the transmission makes, even under a sine drive..
At least they are trying to re-engineer it instead of continue to push a mechanically dicey drive, unlike some companies which will remain unnamed..
I think the best weight/power ratio drive system we have today is the CYC X1 Pro, yet people on this forum have barely touched it so far
. And there is also the astro drive, which is a super nice kit, but comes at double the price.
sleepy_tired said:
Hiding inside of geared hub motors as dual stage planetary reduction gearsets. Kinda sucks when you have fantastically efficient, lightweight, and powerful motor only to double the price and lose all your efficiency gains through a transmission.
Yup, the dual reduction hubs have turned out to be not as fantastic as thought. I don't think that we can entirely blame the gears. Last year, MAC put razor thin 0.27mm laminations in their single stage motors, which only added maybe 1-2% extra efficiency, but they found and improvement and implemented it anyway, out of interest in making the best geared motors on the market, even if it raised the cost of the motor an entire, gasp, 20 dollars.
AFAIK Bafang, as usual, not exactly reaching for excellence, put 0.35mm lams in their dual reduction motors, as well as other manufacturers like Xiongda, etc. These dual reduction motors could
greatly benefit from smaller lams, but again they drop the ball.
The CYC X1 hits the venn diagram in the center of these factors:
Cost ( OK - it's a little expensive at $~800, but the bang for the buck is good )
Efficiency ( Drive efficiency is likely >85% with such an efficient motor, despite the dual reductions )
Power Density ( It contains what is basically a poor man's astro motor and the drive comes in at something like 10lbs? )
Ease of Installation ( It's a mid drive; you could also rig it up to drive the back wheel directly and have a something that's nearly as powerful as a bigass QS motor )
What i think would be the ultimate drive for our ebikes would be a CSIRO pancake motor in a hub wheel, but i hear those things cost tens of thousands of dollars :lol:
https://renew.org.au/wp-content/uploads/2018/12/marand_high_efficiency_motor.pdf