mchlpeel said:
[...]
Grin Tech Rev 4 Torque arm (Em3EV)
Am I missing anything?
I intend to draw 60A continuous [...]
You scratch my back, I scratch yours. I realized those torque arms are sold as singles, not pairs.
From EV3EV's product page:
"Generally a single rear torque arm is sufficient, but for extreme applications, a second torque arm would be a useful addition."
From ebikes.ca:
Is one torque arm enough, or should I use two?
For the torque arms we make with the thick ¼" axle plate, one is almost always more sufficient, but of course it never hurts to have two. Installing a 2nd torque arm will be tricky if you have a hub where the cable exits the end of the axle, as you'll need to cut the connectors off the wire and then reattach them. If you are using a 3rd party torque arm that is made from thinner 1/8" (3mm) metal plate, then we'd recommend doubling up and installing 2 arms.
He goes on to talk about potential dangers of opposite-rotation and back-and-forth rotational force of regen, which I had not considered. He even threw out the idea of having one "preloaded" for frontal roration, and another for reverse rotation. He also said they're developing a torque arm specifically for regen. Worth a read.
I was surprised that Ebikes.ca said right on their product page that he cheapest place for US buyers to get the torque arms was from Amazon:
http://www.amazon.com/s/ref=bl_sr_sporting-goods?ie=UTF8&field-brandtextbin=Grin+Technologies&node=3375251
Current price is $38 for one arm, free shipping. EM3EV is $40, and removing two from my cart took off about $5 in shipping charge.
The way I feel about it is, over 2000W, say with us potentially 3000W and beyond, even if briefly, it seems like having 2 is a good idea. Not so much because the 1/4" plate is not strong enough, but more because he's still using hose clamps, and a nut to keep it all together. To me, even if one would be strong enough, it's like a backup. If one clamp or nut gets loose or wiggly, the other one's there. And if you really did need two, again not because the plates aren't strong enough, but because your frame itself might not be, they're there. To me, the more-symmetrical distribution of force over the frame makes sense. It's painful to drop another $40 after all this. But I'm in for so much money now already. I guess it also depends on how much you like your frame. My bike was more than I thought I'd ever pay for a bicycle, and I bought it mainly for the frame and shocks, so I'm not going to risk ruining my frame over this, and that partly includes me fearing my own screwups. I've also seen aluminum frames break at the dropout just from regular (albeit long-term) bicycle road riding. YMMV. If I had a cheapie steel frame, it might be different.
Are you getting the disk spacer, just in case?
http://em3ev.com/store/index.php?route=product/product&path=41&product_id=89
And on the wiring link in my previous post, it says that wire color coding doesn't necessarily mean anything, that there's no standard. Great. Well, there are at least 2 people already on this forum who have one; at least one, probably have an Infineon; hopefully they will be helpful to us when we try to figure this out.
Update: em3ev sells this "Ebike Tester"; not sure if it helps you figure out how to wire things up. And it seems that figuring out how to use it, might be as complicated as not using it. The little video he includes, with the flashing lights, makes it look like a device from the original Star Trek series.
http://em3ev.com/store/index.php?route=product/product&product_id=87