Xyphota

@wburnes: The eCVTs require a pair of motor-generators to function, but presumably a version that is not intended to provide pedal assistance could get away with a smaller pair of motor-generators

I don't know how long this article has been in the works for, but that titanium RSD with a lauf fork was taken down about 2 months ago and the user account can no longer be found. I remember because I was interested in the lauf fork. I'm 90% sure that bike is a conglomeration of stolen parts lol

For anyone else who had trouble finding what HIP stands for in this context: Hot-Isostatic-Pressuring

@luis-beri: I am also on the 148mm bashing band-wagon, but 148mm should be compared to 157mm, not 150mm. 150mm & 157mm use the same hub shells, but 157mm hubs go into frames that have the 3.5mm recess on each side to aid in wheel installation, which is the same difference between 12x135 & 12x142.

I think this horse is dead lol but here is my explanation for why this mechanism just results in shifting the pedaling circle forward while not increasing any torque to the chainrings: If you look at the youtube video shared above, there is a frame at 1:21 that shows the internal mechanism of the crank arm: https://youtu.be/mJsvrXh3PPI?si=4do6zp45B4D686Cs&t=81 All the mechanism is, is a two sets of bevel gears connected though with a driveshaft. I think one thing that is missing from this discussion is that the bevel gear on the frame side looks to be fixed to the frame, i.e. it cannot rotate freely. Lets pretend that the crank arm is fixed in space so we can consider the pedal arm and the mechanism working in isolation. If we "welded" the crank arm to the frame in the 90 degree position, standing on the pedal would induce a torque that is transmitted to the first pair of bevel gears. This torque is then transmitted to the second bevel gears through the drive shaft. Because the Bevel gear at the bottom bracket is locked to the frame (and not because we "welded" the arm to the frame, this is just how the mechanism works), the BB bevel gear reaction torque must be in the opposing direction to keep the pedal arm from falling when load is applied. Now if we unlock/unweld the crank from the frame, this reaction torque still exists when load is applied though the pedal arm. It is true that the total torque is increased from the pedal to the bottom bracket, but the additional torque provided by the pedal extension will exactly cancel out the counter torque created at the BB bevel gear, so the result is that the torque delivered to the chain ring is identical to the if the pedal arms did not exist at all. The end result is that your feet have moved forward, but no extra torque is delivered to the chain ring.

I think this horse is dead lol but here is my explanation for why this mechanism just results in shifting the pedaling circle forward while not increasing any torque to the chainrings: If you look at the youtube video shared above, there is a frame at 1:21 that shows the internal mechanism of the crank arm: https://youtu.be/mJsvrXh3PPI?si=4do6zp45B4D686Cs&t=81 All the mechanism is, is a two sets of bevel gears connected though with a driveshaft. I think one thing that is missing from this discussion is that the bevel gear on the frame side looks to be fixed to the frame, i.e. it cannot rotate freely. Lets pretend that the crank arm is fixed in space so we can consider the pedal arm and the mechanism working in isolation. If we "welded" the crank arm to the frame in the 90 degree position, standing on the pedal would induce a torque that is transmitted to the first pair of bevel gears. This torque is then transmitted to the second bevel gears through the drive shaft. Because the Bevel gear at the bottom bracket is locked to the frame (and not because we "welded" the arm to the frame, this is just how the mechanism works), the BB bevel gear reaction torque must be in the opposing direction to keep the pedal arm from falling when load is applied. Now if we unlock/unweld the crank from the frame, this reaction torque still exists when load is applied though the pedal arm. It is true that the total torque is increased from the pedal to the bottom bracket, but the additional torque provided by the pedal extension will exactly cancel out the counter torque created at the BB bevel gear, so the result is that the torque delivered to the chain ring is identical to the if the pedal arms did not exist at all. The end result is that your feet have moved forward, but no extra torque is delivered to the chain ring.