E-bike go brrr
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Now this is the level of nerdery I expect.
And this is why the Bosch or Shimano STEPS bikes are so nice and so expensive: Itâs an integrated setup.
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Speaking of this I noticed that a few manufacturers are making ebike specific chains for people that have a motor integrated into the drivetrain. My bike doesnât apply with a hub motor but thought I would mention it.
This one is pretty expensive!
Love this.
The motor mounting is very interesting, didnât realize that was how it was meant to be mounted. With the controller in the way, is it possible to do a rigid mount to the seat stay bosses in place of the cables?
Maybe. I already cut off the canti posts because theyâre where I want to put the battery. I was thinking to build some bracing to the bottle bosses on the seat tube though.
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Super ominous sounds!
I went for a motorcycle ride and saw a guy with a bolt-on e-bike kit with a flat. When I came home 45 minutes later he was still there, so I asked him what tube he needed (26" schrader duh) so I went back home and got the Big Dummy and a tube and a floor pump since he was close to my house.
He was telling me that heâd just installed the Bafang kit and this was its maiden voyage. He had these old âTown and Countryâ tires and had a 1 inch cut in the rear from âriding over a pile of utility bladesâ. He had a patch kit and emergency boots but his tire slime prevented the boot or the patch from sticking where they were supposed to.
He first started removing the tube with the wheel mounted, until he realized the wheel needed to come out. Then he tried to put the tube around the rim and then the tire around the tube over the rim, but quickly decided to put the tube in the tire and then mount the whole thing. Getting the wheel back in the frame also became a two man job as he was pretty befuddled by the chain routing, but eventually we got it in there.
I guess at the end of this I am sort of surprised and maybe a little dismayed that a middle-aged rando can get a Bafang kit mounted on a bike successfully but then have that much trouble with a tube swap. I just canât wrap my head around it.
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Itâs the lawnmower engine DUI bike of the future.
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Nah man weed eater. Lawnmowers donât really come with a horizontal shaft and arenât anywhere close to 50cc which is usually the legally allowed displacement on DUI mobiles
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I believe the term is âDUICycleâ good sir.
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Okay I wanted to run 12v accessories off my battery, specifically an air pump for inflatable bort shenanigans, so I got a DC-DC converter, left center:
I dontâ want it to be always on, so I put it behind the same switch which activates the controller. I also figured it was prudent to add a fuse here (lower left)
Hereâs the thing. The controller has some fat capacitors sitting over the battery rails, on the unswitched side of the circuit. The DC-DC converter seems to also have some fat capacitors over its input. So when I flip the switch, the inrush current into the DC-DC is enough to blow any fuse I put in there. It took out a 15A fast blow and a 5A slow blow which is all I have on hand. This canât be good for the switch either.
WWTD?
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Saw this solution online:
âMix both circuits. The NTC Thermistor will limit the cold current, then the power FET will switch on and bypass the NTC. That way you have both low dropout voltage and if the FET dies short circuit ( the most common failure) you have the power supply overcurrent safely switching all of the unit off for repair. As well the NTC will never warm up unless the FET does not turn on. You can simply have a non resettable thermal fuse in series with the input, thermally bonded to the NTC and the FET, to disconnect the power if the unit gets too hot from this or other reasons.â
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Found another thread which proposed some similar solutions:
You could use the accessory DC voltage to close a relay with 12V coil: this way, the resistor or NTC does not get switched out until the DC-DC converter has started.
Finally got around to messing with the Lorry today and installed the torque sensing BB, wheel, battery, and started mocking up controller placement.
The chainline isnât great with the 115mm Sempu BB. The chainline measures about 51mm now, and thatâs to the inner ring. Itâs probably a 4-5mm increase over stock and may not be a great combo with the 11 spd cassette.
Clearance was tight enough on the NDS of the motor where the wires exit that two of the mounting tabs on the stock brake rotor ended up rubbing hard against the hub. I took about 0.3mm off of each tab with a file and that did the trick. I thought that might be just a problem with the stock rotor, but the Shimano rotor I measured will have the same issue. They both measured 33.3mm between each of the three pairs of tabs.
The Grin triple battery bob works pretty okay with the Lorry and lets you attach it using three of the DT bosses. Only problem was that they didnât include a screw for the countersunk hole at the bottom. Iâll need to track one down.
Using some scrap coroplast for temporary controller mount. Wishing now I would have ordered the kit with the controller integrated into the battery.
Itâs so heavy.
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Terrifying.
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Does that guy share the brain patterns of that free solo guy? No fear receptors.
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Got everything wired up and took it out for a quick test ride. Itâs fun, a little scary, and I definitely need to go through the settings. Even the lightest pedaling is taking it right up to 20 mph and putting out enough power to cause the front tire to slip a little bit under acceleration.
Charging the battery now and will mess with it more later.
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steel motorcycle rims laced to bike hubs?
the âgas tankâ is pretty funny