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[BrianTRice@gmail.com]

It seems like the SR/F analysis is pretty fast right now, so I'm making a separate topic just to track the technical knowledge and some observations. In particular, I'll also be tracking "unknowns" for the sake of soliciting owners to inspect their bikes for answers or ask dealers in case the new owner's manuals don't clarify matters.

First, here's press coverage and the specs page:
- https://electrek.co/2019/02/25/zero-sr-f-electric-motorcycle-launch/
- https://www.motorcycle.com/manufacturer/zero/exclusive-2019-zero-sr-f-review-first-ride.html
- https://www.zeromotorcycles.com/zero-srf/

Known:
- The Calex 1200 charger is gone. The underside of the bike has an air scoop now to direct air to the motor whose fins are now axial vs radial. Honestly, it seems like this can be removed if the motor isn't run at peak performance levels.
- Charging (onboard) is either one or two 3kW (15A @ L1 or L2) units laid horizontally above the main power pack. L1 charging requires an adapter.
- The bike includes a J1772 (or Mennekes?) inlet at the base of the tank near the seat. The cover opens upwards and the plug is oriented towards the side. Potentially, that cover could be susceptible to damage, or the inlet might get some weathering (just something to look out for).
- The tank storage bin includes a dual USB plug for phone/GPS/etc accessories.
- 12kW total L2 charging is available as an upgrade analogous to (if not identical to) the existing 6kW Charge Tank that replaces the tank storage bin.
- The Power Tank has been mentioned in reviews, but I haven't seen any Zero representative or page confirm that.
- The LCD display is replaced by a full-color TFT display.
- The bike seems to have better designed external plastic paneling, and is likely to have much better ingress shielding and management than the S/X platforms.

Unknown:
- The firmware is now labeled "Cypher III" which is a bizarre branding choice. Maybe we'll learn some day what I and II were. We don't know what the architectural diagrams imply yet. There's some IOT mentions which are worth evaluating on a number of levels (security, reliability, relationship of the bike to cloud services, ability to service equipment, ability to recover from a "brick" condition).
- The motor controller's position or model. There are no cooling fins under the tail as there were for Sevcon.
- The location of the 12V battery or related subsystems.
- The location of an accessory charging port or diagnostic ports.

Happily, the frame does seem much more amenable to supporting a fairing. Tubes are easier to brace to without (say) making a weld, and it seems like the bike is made in a way that allows greater precision in dimensions for third parties to build on.

I haven't mentioned the marquee feature-set like increased power, traction control, cornering ABS, cruise control, better ride modes, etc. but they all seem as advertised and will just require some hands-on evaluation to fill in whatever the official manual doesn't cover.

[DPsSRnSD]

Power Tank: The specs page for the SR/F mentions that the 200 mile range requires the Power Tank, available spring 2019.
Motor Controller: There's a photo showing the components with Cypher III connectivity in the Effortless Control section. One part looks like it might be the motor controller. It looks like it would fit directly under the battery. It reportedly can handle 900 amps, and the battery can handle 1200 amps.

[BrianTRice@gmail.com]

Per:
- https://www.wired.com/story/zero-srf-electric-motorcycle-photos-specs-design/

This implies:
- The footpegs, turn signals (aside from coming with LEDs), and mirrors have not changed.
- The dash screen focused on durability+visibility and not touch-sensitivity. (I think this is smart.)
- The wiring harness routes look smarter for servicing.

Other observations:
- Dual front discs (forgot to note above).
- The stock tail sports bars for hooking or tying down cargo or for grabbing.

[DPsSRnSD]

From Motorcycle.com:

Motor and Controller

While the battery box is the heaviest component on the SR/F, the motor assembly comes in second. So, it was placed as low and far forward as possible to keep the center-of-gravity low. This placement also allows for the motor to be cooled without fans. Instead, the lower bodywork scoops the air from below the battery box and directs it over both the controller’s and motor’s cooling fins.

- so, the controller is under the battery.

[BrianTRice@gmail.com]

From Motorcycle.com:

Motor and Controller

While the battery box is the heaviest component on the SR/F, the motor assembly comes in second. So, it was placed as low and far forward as possible to keep the center-of-gravity low. This placement also allows for the motor to be cooled without fans. Instead, the lower bodywork scoops the air from below the battery box and directs it over both the controller’s and motor’s cooling fins.

- so, the controller is under the battery.

Ah, good catch. This is why I made a forum thread - for more sets of eyes to surface and corroborate details.

So, it won't take much teardown to find out what controller was used and how it operates. Hopefully the ingress rating / management is impeccable because we know that chargers take a beating down there!

[BrianTRice@gmail.com]

- The "Bosch Motorcycle Control System" is called out "which includes advanced control features from anti-lock brakes to cornering assistance". This seems to be: https://www.bosch-mobility-solutions.com/en/products-and-services/two-wheeler-and-powersports/riding-safety-systems/motorcycle-stability-control/
- The motor controller is rated at least at 900A (battery side, unknown voltage but peak power is listed at 82kW, and 82kW / 900A = 91V, surprisingly, so the controller minimum voltage may not have changed much).
- Progressive regeneration based on throttle position near the resting stop is called out at least in certain modes/scenarios.

[Richard230]

No one has mentioned yet that the bike uses dual discs and radial-caliper brake systems on the front wheel. Radial calipers typically provide improved braking feel and power. Also, the Showa fully-adjustable big-piston SFF front fork suspension is a nice upgrade over previous models.    Just the chassis upgrades seem worth much of the increase in price, much less all of the other stuff included in the SR/F.

[BrianTRice@gmail.com]

Thanks for calling out braking and suspension details and benefits. They’re uncontroversial and thankfully straightforward.

I’m not clear yet how I’ll carve up the manual and website to accommodate these system variants by platform, and am betting on my time and money freeing up soon to support the effort, because right now I lack both.

[BrianTRice@gmail.com]

It's becoming clear to me that the engineering team adhered to a design philosophy treating the main powerpack or subsystems immediately adjacent to it as a sort of hub.

On the S/X platforms, full current runs from the back of the pack (or modules) to the tail where the controller is, which then routes its output down through the center to the motor. This means that the thickest power cabling runs through a considerable distance within the bike, which is what makes the center of the S platform so cramped.

By positioning the controller nearly against the battery (one assumes there's a contact gap of ~3mm between the battery casing and the controller and charging units), the 900A of current conducts through a very short of cables or possibly even bus bars.

If we're lucky, this means that the MBB and other systems one might want to access or swap may be in remote positions like the tail, so lifting the seat reveals most diagnostic connections in addition to limiting high voltage exposure (primarily 12V circuits and busses).

I'm noticing a number of keyed panels in photos, and it looks like the seat is keyed now. So that suggests that the seat now only exposes 12V systems and is therefore safer for customer access.

All in all, it looks like we now have a proper electrical distribution "star" architecture that should be easier to reason about and move around safely within. If so, good job to that engineering team.

[BrianTRice@gmail.com]

One more piece of hearsay/inference to note: the cells in each "longbrick" are laid out vertically (thin side up) with the cell face aiming forward.

The connections between cells would then presumably run along the "spine" through the middle of the pack.

This is all inferred from the existing longbrick design and comments about what the battery case fins are meant to accomplish (ensuring that cells in the middle are nearer to the temperature of cells at the front of the pack).

[BrianTRice@gmail.com]

The Cypher III control system diagram just shows a cycle with Cypher III at the center, with a flow of: Motor, Phone, Battery, Controller (heatsink), Dash, back to the Motor.

Basically, it's the MBB/ECU. The flow is just hand-wavy Powerpoint feel-good stuff, as far as I can tell.

Sure, we might discover that there's a smarter protocol in there than CANBus/CANopen. Maybe they've changed the control architecture so that the MBB is more like the "MCP" (Master Control Program from the TRON movie script).

But it's not a nice neat package like the Z-Force trademark represents, and it doesn't appear very explanatory yet. I mean, given that diagram, I can't figure out what questions or hypotheses one might be able to answer that one couldn't before. Maybe they just want "Cypher Three" to be an easy phrase to say over the phone or in email exchanges to communicate service issues.

[ESokoloff]

Per:
- https://www.wired.com/story/zero-srf-electric-motorcycle-photos-specs-design/

This implies:
- The footpegs, turn signals (aside from coming with LEDs), and mirrors have not changed.
......

I think the turn signals unfortunately are incandescent.

[Curt]

So the trouble-prone Calex is gone, nice.

But there must still be some form of DC-DC because a 12V battery couldn't provide 350W continuous.

The 12V battery is a new maintenance item. I would imagine it's much smaller than a YTZ12, not having to provide big CCA. But it might draw mA similar to a cell phone 100% of the time. If it's small, like 1000 mAh, the bike might need to tend it periodically.

The App description indicates you can upload data on torque/power/speed/location/lean angle. What kind of sensor can detect lean angle? Not an accelerometer. I suppose an accelerometer in conjunction with GPS!

This bike really is a new platform and will probably more than double the size of the unofficial manual.

[robbill]

What kind of sensor can detect lean angle?

Hasn't the Bosch stability system got lean angle sensor? Think there's a mention of cornering ABS, may also be used for traction control.

[Richard230]

What kind of sensor can detect lean angle?

Hasn't the Bosch stability system got lean angle sensor? Think there's a mention of cornering ABS, may also be used for traction control.

BMW started offering this system last year and was charging something like $500 for the download that would make it work on their latest models that have a lean angle sensor (like my 2016 RS).  I think they did that to keep up with Ducati, who first introduced the feature a couple of years ago, but at no additional charge.    This is likely a worthwhile safety feature for anyone who has the guts to slam on their brakes while in a corner - unlike me, which is why I didn't pay for the download. I might add that the system also keeps wheelies under control.