Recent content by PaulD

If you're considering 10kw, I wouldn't gear the motor to spin your chainring at typical pedaling cadence.

This is an old thread, but there are a number of ways to improve the odds of your cassette and freewheel surviving very high power. Use only the sprockets that are 16T or larger Use a shift sensor - generally side loads during shifting are what kill your chain Have a freewheel on the motor...

Cool. Looks really tough. This one was shown at the Sea Otter that has a "diamond ceramic" coating: https://bikerumor.com/onguard-rock-solid-u-lock/

It looks like there isn't a freewheel in the system to prevent the chain from over-driving the pedals. So, if you stop pedaling suddenly, is the motor and gearbox inertia going to throw your chain off the chainring or break the derailleur? Also, does that torque sensing device work in all gears...

UL 2271 does not have any puncture or thermal runaway test. It is mostly electrical and software tests to ensure the BMS functions properly. The mechanical tests are shock and vibration (similar to UN 38.3), drop, and a few others. The ingress protection tests are very lax. There are also a...

Going to 48V would increase the crank/motor speed by 33%. That is more than it is designed for. V4 will be very similar to V3. Off the shelf low offset JIS square taper ebike cranks are compatible. Miranda makes 155mm i believe.

- I'll have an update with new pricing in the next few months. And only 36V batteries are compatible. Higher voltages result in motor and crank speeds that are too high. - No hot rodding allowed :-) There isn't much thermal overhead, and with a small battery more power is just going to drain...

122mm must be the BB spindle length, not the q-factor. Even pure road bikes have 150mm+ q-factor. You need to add the offset from the crank arms. At this time, the numbers I mentioned above are the only option. This is limited by the torque sensing BB.

Q-factor is about 180mm for a 73mm BB. Q-factor for a 68mm BB is about 175mm. Offset is 3mm towards the driveside. If you use an extra pedal washer or two on the non-drive side that would be pretty close to symmetrical. More info is here: Mid drive kit — Revel Propulsion Ebike Mid Drive...

The short answer is yes. I do still plan on making another batch. I can't pinpoint the date yet, but it will be this year. I'm bogged down with a few big projects right now.

UL may weed out the worst of the junk, but there are still some shady batteries that get certified. If you've ever seen the inside of a UL certified Ecotric battery, it looks just like any other super cheap battery, except there is redundant circuit protection in the BMS. It doesn't matter if...

I think that makes sense. When the BMS triggers that fuse, it ties the heater to ground, which puts pack voltage across the heater, which means after triggering, the output side of the fuse could be tied to ground, and the battery side would of course still be connected to battery positive.

Would you use "remote assist mode" address 506?

This might be it, but you should check the dimensions. Suzhou Cusmade Electronic Technology Co., Ltd. Is there any branding molded into the connector?

Woah. Problems with USPS?? That battery is almost 10X bigger than the legal limit to ship via USPS. Please don't ship batteries illegally.