Recent content by tomtom50

I bought a Aikema Q128H because it is 800W and a slow (200rpm) wind, but still you can't climb slower than 8mph (700C) before it gets inefficient and generates too much heat. Fortunately it is powerful enough so I can manage 8mph up pretty steep hills. The only better geared motor for climbing...

I'm glad to see some work on the human torque reading. My TSDZ2 flatters me daily, my old bones push 200W so easily... A decent check could be done with rollers. On zero assist pedal a while at a steady speed and get a good human watts reading. Then in the same gear use throttle only to reach...

Nice explainer!

I just built a Shimano Nexus 8 wheel and tried it out. Everything worked as it should. I used it two days and reinstalled the derailleur. Shifting with an IGH means breaking stride, and especially on a hill you slow down. Shifting was slow and annoying, to the point I avoided shifting. Some...

Unfortunately it isn't so simple as safe / unsafe amperage. Motor temperature is commonly controlled by watching I2t (Current squared with duration factored in). http://doc.ingeniamc.com/emcl2/command-reference-manual/protections/i2t-protection This type of watchdog function is built into...

I showed it to a very smart electrical engineer at work, and he was impressed by the simplicity. Here is what he said in non-technical language: The two coils are, as you said, a transformer. An alternating current on the bike side induces an alternating current in the rotating coil. The...

You can increase power two ways: 1. Increase the allowed amperage in the manufacturer firmware. 2. Install the open source firmware and set a higher power level. This is harder and you need to wire in a different display. (KT-LCD3). 350W at 36V is 9.7 amperes. You can overheat your motor if...

Use bikecalculator.com I ran 80kg weight, 20kg bike, with MTB tires, 35kph requires 340 watts at the cranks. ebike motors are about 80% efficient when operated at a good rpm. 80% efficiency means 80% of the electrical power into the motor goes out as shaft horsepower, 20% of the power is...

Various epoxies claim to fix this type of failure, but they replace a material that failed with something weaker. The best fix here, if there is depth, is to use a tap drill, drill deeper, tap the hole deeper, and use a longer screw. The new threads will be as strong as the old threads were...

There are a lot of posts, but the basic idea is simple: The stock voltages are best for most people, only riders with a higher than average pedal cadence (>90rpm) should consider a non-stock setup. If your natural pedal cadence is 90 rpm or lower there is nothing to consider. Buy 48V and run it...

Let us know if you try it. Sounds like fun. I’m thinking of changing my 11-36 freehub to a nexus 8-speed. Almost the same range.

Would a belt cog at the cranks match up with the back cog? (Beltline)

50mm from the CENTER of the BB

See https://www.sheldonbrown.com/chainline.html Typical derailleur bike chainlines are 43.5 to 50mm. TSDZ2 is 50mm (standard dished 42T chainring, flat chainrings have bigger chainline). Most IGH hubs are 40.5 - 42mm. So you will be off 8 - 9mm if you use a flat sprocket. Keep in mind...