E-bike talk: not tech rumor derailment

Hope now makes a rotor that's directly compatible with the Avinox speed sensor, pretty clean!

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PRESS RELEASE

Our new Avinox Speed Sensor Rotor is based on our proven Fixed Rotor design, with speed sensor slots machined directly into the disc. This integrated design eliminates the need for a separate speed sensor ring, offering a straightforward solution for Avinox equipped e-bikes.

Key Features

• Available in 200, 203 & 220mm
• 6 Bolt disc fitment
• 2.3mm thick
• 2.3mm Material offers superior stiffness, strength, vibration damping and thermal stability
• High quality disc laser cut from a single piece
• Robust option suitable for most applications
• All rotors come with relevant hardware to fit to hub
• Laser cut stainless steel braking surface
• Avinox Speed Sensor slots integrated into disc
• RRP £45.00 // €56.50 // $62.40 (ex tax)

Available to order through any local Hope Dealer.

sounds like a custom sensor pattern would defeat speed controls. 

This must be a new thing in general as my Orbea has the same type of thing, but made by Galfer. It is a nice integration. 

Speaking of electric drives, 

https://www.youtube.com/watch?v=7p5LxFdc-Qg

I still like the Pinion MGU.  If it were available in the US, that would be my next bike for sure.

Mind extrapolating on how the chain tensioner feature? I saw the update that included it, but I honestly haven't noticed a significant impact on ride feel. We're mostly winch-plummet riding on fire roads here though. 

Bosch added some cool features with the latest update, adjustable traction control, you can select fast or slow charge (if you have the yet to be released fast charger), a timer that shows how long to charge fully, and most controversial 1000 watts is incoming.

I was messing with a Lezyne light that plugs in to my Bosch motor yesterday and that has some cool features to, like auto adjusting brightness, etc. It's a very feature rich motor. 

The tensioner spins the chainring until it feels chain tension (via the torque/power sensor).  They put this in apparently for people who are doing a lot of rolling trails or climbs with off/on pedaling to make the motor as immediately responsive to pedaling.  This results in the motor running constantly when descending, and removes the Ochain-like behavior that most ebikes enjoy (due to the freehub behavior at the chainring).  I was in the camp of hating it, and am glad it's off by default now.

I don't know about "feature rich". Avinox has forced these things upon them, as it had that stuff out of the gate. Including a fast charger that you can actually buy.

I have seen a custom ring with 21 "holes"...bike thinks it is going 1/2 as fast as it is. Braaaaaap. More power. Theoretically take it to 56mph.

Which systems does that work with? AFAIK a lot of motors will basically brick themselves if they think the wattage output vs speed is being tampered with. 

All the speedometer is there for is to cut power to the motor so it shouldn’t make a difference to any other aspect. I’ve seen someone move their Shimano speed sensor to their crank to unlock the speed limit. It’s hard to say for sure though with so much software, I just noticed avinox can detect what gear you’re in even with a mechanical drivetrain. 

Bosch, for example, will brick itself over a swapped chainring, if my rep is to be believed. The motor knows you're not going to be going half the speed if you're putting out full wattage, and makes note of it, barring it from getting warranty via Bosch. System can only be unlocked via an authorized dealer. I'm sure you could do some sort of software flash or something to change the system, but it's a lot more involved than changing a speed sensor. 

These systems are fairly robustly designed in terms of RPM, wattage, and speed. They have a decent level of idea for when they're being messed with. We've been told by a few companies that messing with these systems will revoke our access to working on them via the proprietary software. 

So yeah, I'll plead ignorance insofar as I'm not aware of which motors would have issues, and if Avinox would be part of that, just something I had considered. 

I frigged around with the etuning app on a shimano e7000. Made the wheel size smaller so the registered speed was a touch faster than shown. Still has 60nm so it doesn't climb very fast but the higher cut off speed was nice for hitting jumps that may need a few pedal strokes. When i bought the motor it was set for a 29" rear wheel and mine is 27.5. It was unnerving getting committed for a gap and the trail , or me, was running slow. I'd go for a few pedal strokes and it was like i dropped and anchor as my speed was already over the registered cut off speed. Same with all my in town grass hits. After a bit of rain i couldn't get enpugh speed that the wet grass wouldn't kill before i hit the lip. I tried the wheel size set at 26" and a few extra pedal strokes and then the motor over run and the thing was flying. I started thinking sl power emtb's with a higher cut off would bd nice for jumps and not cause any extra trail conflict because the low power limits their climbing speed. I only really noticed the difference on downhills when i needed a pedal stroke. A nice feeling when you needed it

I'm riding a 2021 bullit and I burn through two 630wh batteries pretty easily riding in trail mode. I want to get my laps in. I don't ride an ebike to suffer in eco mode. 

I'll die on this hill... I will never buy an ebike without an easily swappable battery. I see absolutely no point in having all the power that an avinox motor provides if I'm gonna kill that battery in two hours and be done riding for the day (or waiting an hour for it to charge at minimum). 

Which motors allow the chainring to spin backwards freely?

The 21 slot reluctor rings are intended for Avinox bikes, but I haven't seen any ride reports. You're right that with all the software, algos, and sensors, Avinox could easily identify the change. Bosch will go into a limp mode or cut power entirely if their tamper alerts are triggered, which has certainly been known to happen when people try to monkey around with these things to get more speed out of them, but I am not sure if Avinox takes a similar approach.

Having said all of that, for riders in the USA and NZ, I really don't see much point in the aftermarket 21 hole ring. In most cases the Avinox bikes in the US can be switched to class 3 mode, and that is the default in NZ as well, so there isn't much to be gained, and a lot to be lost with one of these rings. For folks in the EU, or AUS, I guess it might have some appeal, but people seem to prefer other methods to achieve those ends anyway, that avoid all of your speed and distance info being off by 1/2.

Off the top of my head, the only motor that doesn't let the chain spin backwards relative to the crank is the TQ50 (check some of the reviews of the Rallon RS which uses it).  On the rest, if you backpedal the crank, the chain doesn't move.  The reason being that without that, on every compression of the suspension, the chain & crank movement gets interpreted as a pedal stroke and activates the motor.  A common theme among the Rallon RS/TQ50 reviews is reviewers turning the motor off when descending to avoid getting uncontrollably boosted down the trail.

"the only motor that doesn't let the chain spin backwards relative to the crank is the TQ50"

"On the rest, if you backpedal the crank, the chain doesn't move."

But when you backpedal the crank, the chain is moving forward relative to the crank, not backward.

If you try rotating the ring backwards while holding the crank steady on most motors, it will definitely engage the clutch/ratchet and rotate the crank backwards with it. There is some freeplay between the two, depending on the clutch design, so that may have an Ochain like effect to some degree, but I guess it would depend on how much chain growth the bike has and the degrees of free movement available before the clutch engages.

I don't know much about the TQ50, but if I recall correctly, the TQ40 only has a single clutch, rather than double, so in that case I think the ring will move when you backpedal the crank. The problem with that, is that the crank will also move when the ring is driven, so motor activation can rotate your cranks forward unexpectedly, whereas double clutched motors can power the ring without the crank getting spun.