Levo Gen4 derestriction with PLANET3

[Alex @ PLANET3.bike]

Hi all,

I've been waiting until I got my personal bike (Gen4 Comp Carbon) to test and make a post regarding the PLANET3 and Levo Gen4. After testing this weekend here are some findings in order of importance..

• Specialized has finally gone the route of Giant/Shimano/Bosch and the new system is paying attention to gear ratios i.e. cadence vs. speed "map". This means that the days of derestricting it fully via a mechanical planetary gearset with a 3:1 ratio are basically gone. It's not that it doesn't work at all and for some use cases it's perfectly fine, but with a 3:1 ratio you'll get an error in anything lower than 8th or 9th gear.
• With a dual planet set the ratio of PLANET3 is halved to ~1.5:1 but even with this config the Gen4 Levo will cut your power in the first 3 gears (largest cogs on the cassette). The rest works fine and the speed limit is raised 50% (for EU/UK this is from 26-27 km/h to ~40 km/h while for the US it's from 20 mph to 30 mph. Yes, some of you will say that this is unnecessary as the US spec bikes come with the selectable option to go from Class 1 to Class 3 (28 mph), BUT what most people forget is that this option also halves the power output of the bike from 666W to Levo SL levels of power and good luck reaching 28 mph on flat asphalt with that power. I don't know about you but I've personally never used the lowest gears (even on a Gen2 Levo with a lot smaller cassette), but I might not be a good "population sample" since I mostly use my bike as a personal shuttle for relatively low-inclination fire roads climbs because of my hip flexion problems (I can't really bend forward and put pressure on the pedals without pain). Still, even when I chose a really steep incline and put the bike in down-tuned Eco mode, it's not really necessary to use the first 2 gears and it's my opinion that they're mostly there for situations when you're in OFF mode or you're climbing with some "acoustic" bike people. However, potential users should be aware of this limitation.
• The way that Specialized is currently checking this cadence vs. speed map is that they need a sample of ~25 seconds of CONTINOUS pedaling and then the bike cuts your power if you're in an "impossible gear" for a given combination of cadence and speed. If you stop pedaling for 1 second every 20 seconds, everything works but it's really a stupid way to ride. However, for a scenario when you're doing bike park downhill runs and you don't need to pedal for more than 20 seconds at a time i.e. you're just throwing in some pedal strokes here and there before jumps and you want to be sure you've got the power there - a single planet config works wonderfully and the speed limit goes to 3x the regional speed limit.
• What currently happens when it cuts your power is basically nothing. Bike cuts your power, no error messages appear on the screen, no error messages appear in the Specialized app. I will have a result if anything is visible in Specialized Turbo Studio (dealer app) in a few days, but for now - it seems that the power cut is the only thing that happens and it goes away as soon as you restart your bike. This doesn't mean that in the future they might not "upgrade" this to a more severe action that might void your warranty BUT the error that was present for this event in previous Specialized firmware was just aimed at "it looks like you've got a smaller or larger front chainring than is mechanically allowed in our system, please visit the bikeshop for a list of allowed ratios and change it back". Of course, if you're using a 3:1 ratio device that basically adds 300% to the cassette and if you're in 1st gear (51T on the cassette) the bike expects to be moving at say 6 km/h at a given cadence but the speed sensor is reading 2 km/h - then they can use that and say "hey.. there's no 150T cog on ANY cassette out there, so you're being a naughty boy and you need to cut that shit out!" but in my experience with more than 10k units out there on Specialized e-bikes - this hasn't happened yet.
• I've been delivering devices with a dual planet config by default for more than 2 years because I was expecting this moment to come even for Levo Gen1/Gen2/Gen3 i.e. Gen2 Brose S-Mag, but this never happened and the previous Gen bikes can still be fully derestricted with a PLANET3. For these bikes and motors we're safe anyway because when I found out about the potential error in the firmware that reports "Gear ratios outside the allowed range" I didn't just start delivering the mechanical devices with dual planets, I wasted a lot of time and effort to develop the PLANET3-E chip version which takes care of this problem in a much better and future-proof way.
  
  
• Next thing I'm doing is cutting apart my Gen4 Levo connectors because just like previous generations of Brose, they're not available in the connector industry (Gen1-Gen3 were Brose connectors, Gen4 uses a combination of Higo and Chogori but even though these are usually available through Alibaba, these exact variants are OEM specific and they won't sell them to anyone), and I'm proceeding with making the tooling to injection mold these just like I've done with the previous gen Brose connectors. This will take some time and the development of PLANET3-E for Gen4 is not something that will be done in a matter of weeks but a matter of months.

TL;DR version is this: Gen4 Levo can be derestricted to ~40 km/h (EU/UK) or 30 mph for US with a dual planet PLANET3 config IF you're OK with not using the first 3 gears. If you need it for high speed runs in bike parks then even a single planet (3:1 ratio) device works so long as you won't be doing continuous pedaling for more than 25 seconds in gears lower than 8th or 9th.

In terms of compatibility, all the Gen4 bikes are covered and you can check them out here: Levo (Gen4) - PLANET3

1. For the Comp Carbon model (and all the lower models that are yet to come out), it's necessary to replace the hub end cap and axle assemblies because it features an incompatible concave profile by default. All of this arrives in the kit and it's installed in less than 1 minute by simply pulling the old end cap and axle (by hand) and inserting the replacements. The rest of the installation is pretty routine and the same as all the previous generations of the Levo PLANET3 devices.
   
   
2. For the S-Works model, it's also necessary to replace the hub end cap on the DT Swiss 240 DEG hub because it features a conical end cap profile which we can't grab a hold of via press fit. Thus, I've machined sexy replacement end caps that are basically identical to new DT Swiss 350S hubs with the little tool-free removal groove at the top, but the rest of the profile is straight 19mm diameter which plays nicely with PLANET3.
   
   
3. For the Pro and the Expert models they come with hubs that are natively compatible and you just fit a PLANET3 as if to any other straight 19mm diameter profile hub.
   
   

If I remember anything else I'll edit this post, and if you've got any questions - fire away.

Regards,
Alex

 

[DylanJM]

Great work Alex!

 

[Alex @ PLANET3.bike]

Great work Alex!

Well, not really (yet).. This was more of a FYI in regards to limitations because other providers of a similar service/device don't seem to want to be transparent with users in regards to limitations of the mechanical derestriction devices.

 

[DylanJM]

Well, not really (yet).. This was more of a FYI in regards to limitations because other providers of a similar service/device don't seem to want to be transparent with users in regards to limitations of the mechanical derestriction devices.

This is precisely why it's great work. You are the only provider offering any sort of insight to the development process and challenges faced when working on derestriction solutions.

Have you been able determine if Specialized have added any measures to combat the use of speed chip solutions? From what I gather with the previous gen motors they were somewhat easy going compared to Bosch, Shimano, etc. I wonder if this will change with the gen 4?

 

[Alex @ PLANET3.bike]

Have you been able determine if Specialized have added any measures to combat the use of speed chip solutions? From what I gather with the previous gen motors they were somewhat easy going compared to Bosch, Shimano, etc. I wonder if this will change with the gen 4?

For Gen4 the answer is - I don't know yet. On Gen2/Gen3 they're all pretty much the same - if you can get access to CAN messages between the display/motor/speed sensor and simply modify the value of speed given to the motor to stay below the limit (~80% of the speed limit is what most chip makers use) then no manufacturer uses the rest of the available hardware to fight derestriction that actively.

For example, some displays/TCUs have barometers i.e. altitude sensors, Giant e-bikes have an inclination/tilt sensor. However, even though an algorithm could be written to detect potential cases of tampering i.e. power being drawn like you're climbing while the bike is still horizontal and the tilt sensor is not saying you're going up - they're not doing any of this because either they don't want to and recognize there are potential scenarios where it's perfectly plausible (say you've got a monstrously obese wife or you're so goddamn fertile that you've managed to reproduce an army of little minions, and you're towing your clan behind your e-bike on the flat) OR they are willing to look the other way and make my job easier (which I don't buy for a second). Bosch is cheating and know this for a fact because they basically say "if you've never hit the speed limit and kept pedaling without power, you're cheating" so, we just make sure to hit the speed limit occasionally - just like all the manufacturers circumvent the 250 W nominal power rule of law (we know all the motors continuously provide 600W+), but if you put them on a dyno or log the CANbus you'll see that every 30 seconds the power will drop back to 250W for a few miliseconds. You don't feel this but the rule of law is satisfied and you can surely pedal for 15 min in Turbo mode without ever feeling any power drop.

Specialized, for example, since day one of Gen2 Levo had the Mission Control draw a map of your ride using the GPS data but exclusively used the speed sensor data for distance and speed. It'd be ridiculously easy for them to simply compare the two and say "hey, you're being a naughty boy!" but they don't. Also, don't be a twat and use the official app that will provide the manufacturer with data that is direct evidence against you.. Main advantage of Specialized e-bikes was a lack of any screen bullshit.

On the Gen4, they could without ANY issue do what Shimano cunts do with Di2 derailleurs. Since all the bike Gen4 Levos come with AXS derailleurs which know exactly in which gear they are, they can use this information along with the motor cadence and the wheel circumference to calculate speed very accurately. You don't even need a speed sensor any more. And I believe they already do this 100% because that's the math behind the smooth power delivery and less wheel slippage when climbing on loose terrain. Same as DJI Avinox, they will display ON THE SCREEN in which gear your bike is even though you have a mechanical rear derailleur and no sensor for position. This can all be done and maybe it will be in the future, but for now they're leaving it alone.

As things progress in the future, manufacturers might simply lowjack your bike with GPS and you will agree to it via a standard EULA when you buy the bike or register for the app and then they can use this info against you.

Anyway, keep your wits about you, don't perform unnecessary updates, don't use apps and screens if not necessary - if you want your derestricted e-bike to keep working.