littleskull99 said:
John, do you have a build thread going for your bike? Thanks. Matt.
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I appreciate the interest. I've been using this bike for over nearly 4 years. It's been primarily a test platform thru a number of performance upgrades and changes. I've shared some pics along the way, but it ain't pretty though what it does is beautiful. Below is close to how it's been for almost a year, but the pic is missing the front moto wheel I run now. The hodge-podge of batteries (over 20ah of 30s) are in the swingarm and bolted to the frame with a healthy dose of duct tape. It may not look it but the rig is fairly water resistant, and all batteries are rigidly secured.
Now that I'm not just winging it and have a better picture in my head of a slick end result, only an easy swingarm mod puts 10ah of 30s or 31s in the swingarm, I'll try to get more pics of the process. I'm still flip-flopping on the quantity and placement of more batts, and whether to do something with the controllers. Those will all dictate wiring cleanup. Inside the main tube is out, because it has a solid plug of fiberglass cloth with epoxy vacuum infused to prevent a failure at the shock mount already cracked when I bought the frame.
Very soon my HubMonster driven SuperV will be proven the fastest and quickest hubmotored bicycle frame based ebike in the world, so it needs to look the part. That will be with 270lb me aboard, so imagine performance with a normal weight person.
IR is super important for batteries, the lower the better. The same is even more true for motors. Low phase-to-phase resistance is the route to high efficiency and power, with our BLDC motors.
Copper losses = current squared X phase-to-phase resistance is a sobering fact, especially when you consider hubmotors are limited only by heat. Don't forget resistance in copper goes up about 0.4%/°C at our operating temperatures, so guys running their motors at the high end of hubmotor thermal limits are creating up as much as 50% extra copper losses compared to the motor at ambient. The cooler the better. Ignore heat at your peril, because that simply forces you to buy and carry extra batteries to make heat with. High current is meaningless without low resistance. At 0.016 ohm phase-to-phase resistance, supposedly high performance hubbies in HubMonster's weight range have 5-7 times higher resistance.
Combine high quality laminating steel with a low slot and pole count, and you keep iron losses low as proven by a no-load current of just 2.7A (186W at 69v) at 1260rpm, and 3.4A (365W at 107v) at 1965rpm. Imagine an extremely well built RC outrunner with a Kv of 18.3rpm/v that weighs 15.5kg, but it's sealed in a steel shell with a thick aluminum cover on just the wire side...heavy but the big majority of the weight is the stator. There's no empty space inside unlike the caverns in other hubbies (air is an insulator not good in our heat limited motors),
HubMonster is all motor baby, and that lack of air volume means better heat transfer both sealed and ventilated. When ventilated, the lack of open wasted space forces air sucked thru HubMonster to interact more directly with the exposed parts, for better heat transfer directly to the outside world.
John
I'm expecting a whole lot less sag with the nanotechs. 8) 
Less than 3V of sag at 250A sounds good to me with 20ah either route, and about 5V of sag with 10ah is a big improvement over the 16V I've been seeing. 
