So the conclusion is titanium torque arms and clamps or dropouts, with a torque-controlled variable gravity generator at the rear to keep you from flipping over, and then you can run whatever power motor you like in front? :lol:
chvidgov.bc.ca said:Would the results of single-dropout-at-a-time type testing be the same with two dropouts installed as per normal - ie. is the total torque applied distributed equally over the two dropouts, leading to a larger safety margin than the above tests would indicate? This would seem reasonable?
dequinox said:I need to get on replacing my other bike's front fork, and then I can donate an aluminum fork. It's cracked at the brace though Justin, can you still use it? By the brace I mean the little arch that holds the two pistons together or whatever...I'm not up on the bike part jargon.
electricwheels.de said:Just worked my way through 11 pages of postings regarding the testing of dropouts and torque arms.
Here in Germany we are just having a similar discussion in our forum, so you can imagine how I lapped up all the info . Great work, Justin.
I've worked on a torque arm design myself, and have come up with a modular design to fit most bikes. Currently only for M12 axles, with M14 axle fit coming up.
What do you folks think of this one:
I make them in front and rear versions, and would be gladly sending some samples over for testing and evaluation if you are interested.
If you like more info, just read through the mounting instructions. There is a 3D explosion drawing in there as well.
http://electricwheels.de/torque%20arm.html
Jeez, it's getting late again...
electricwheels.de said:Just worked my way through 11 pages of postings regarding the testing of dropouts and torque arms.
Here in Germany we are just having a similar discussion in our forum, so you can imagine how I lapped up all the info . Great work, Justin.
I've worked on a torque arm design myself, and have come up with a modular design to fit most bikes. Currently only for M12 axles, with M14 axle fit coming up.
What do you folks think of this one:
justin_le said:It is true that in normal use, the torque of the motor driving forwards will cause the torque arm to rotate backwards and into the frame, so the tie is under no tension. However, when there is a fault with either the hall sensors or a shorted mosfet in the motor controller, then the torque can pulsate very heavily in both directions with significant jarring force, and I don't think that your cable tie could handle this.
It's pretty easy if you are a bit brave to test this out by riding your bike with no controller and an ON/OFF toggle switch between two of the phase leads. Then, once you get up to a good speed (say 30-40 kph), close the switch to short circuit the motor phase wire and see if the torque arm holds the wheel in place or if it tears out. I'd wear a helmet and pads just in case! -Justin
justin_le said:Next up was to try it with the wider 14mm axle. I only got 2 tests of this in, one with the nuts hand tight and the other with the nut tightened to 60 N-m.
Code:Nut Torque Axle Spinout Torque hand tight 49.5 N-m 60 N-m 79.9 N-m