Grizl:ON CF 7 - Puppy Delivered to Vet

Sounds about right. IIRC, when I was considering bikes with the Sprint motor the Bosch range calculator was showing 35-45 miles for my typical riding speed/conditions. 10wh/mi in decently rolling terrain with moderate assist. High speed >mid20's mph eats battery, but the real range killer in urban/suburban rides are the many stops and accelerations. I'm always surprised when I get out on a trail how the range improves.where you can push a steady pace for miles.

FYI, it's likely your speedo is reading fast. Bosch is kind of notorious for that. On my older bike the power drop off starts at 26.5 (actual) mph and is mostly gone by 27.5mph. My newer bike is probably about the same though I haven't bothered trying to calibrate too close - its speedo is somewhere btw 2-2.5 mph fast. Assist drops to imperceptible at 29.3mph (per the speedo) for me.
 
BlackHand said:
Sounds about right. IIRC, when I was considering bikes with the Sprint motor the Bosch range calculator was showing 35-45 miles for my typical riding speed/conditions. 10wh/mi in decently rolling terrain with moderate assist. High speed >mid20's mph eats battery, but the real range killer in urban/suburban rides are the many stops and accelerations. I'm always surprised when I get out on a trail how the range improves.where you can push a steady pace for miles.

FYI, it's likely your speedo is reading fast. Bosch is kind of notorious for that. On my older bike the power drop off starts at 26.5 (actual) mph and is mostly gone by 27.5mph. My newer bike is probably about the same though I haven't bothered trying to calibrate too close - its speedo is somewhere btw 2-2.5 mph fast. Assist drops to imperceptible at 29.3mph (per the speedo) for me.
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Could be... but I note that @Mr. Coffee (back in 2018 or so) calculated that speedometer error on his Bosch CX line was in the low single-digit percentages. I could believe it's off by 1 MPH, but I think it's just as likely that because the wheel size is odd (28 inches, which I love, as it turns out), they may not have set the limit on the motor quite right. Without a radar gun or a pace car with a tested speedometer, we'll never know.
 
My Bosch powered bike reads 1mph high, so I don't use the speed reading through the Kiox at all. I have a Garmin speed sensor on the front hub, and connect it to my 840, which I have set on "Auto". The 840 measured wheel circumference is within 2mm of what Schwalbe publishes for the Big Ben tire. Eventually, I'll roll it out to check.
 
stompandgo said:
I have a Garmin speed sensor on the front hub, and connect it to my 840, which I have set on "Auto".
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Isn't the 840 a speedometer itself based on the GPS readouts? Why the redundancy?
My 540 is connected to Vado 6.0, and the Wheel Circumference is Auto there. The reported speed and distance are very accurate; the distance ridden matches the Strava map data to fractions of a percent. (The speed accuracy is confirmed by public speed radars of the area where I live). Interestingly, Wahoo allows Auto for any bike or e-bike unless it is a connected e-bike; the latter requires entering a fixed wheel circumference value.

I think the Grizl speed discrepancy might be caused by a wrong Wheel Circumference in the e-bike system. Let me give you a real world example:
My female riding mate Anna owns a Bosch e-bike. On our early rides, Anna rode very slowly, just barely above 21 km/h but she told me the display reported as many as 25 km/h, and she was experiencing the speed restrictor on whenever she tried pedalling stronger. I confirmed that by riding my Vado SL side by side with her, and watching my and her speedometers. I recommended to Anna she should see a Bosch dealer and she did so. Turned out, the Wheel Circumference in the e-bike system was half a metre wrong! After the change of WhC by the dealer, Anna's e-bike started behaving normally, and could be ridden faster, with the actual cut off speed of 25 km/h.
 
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Stefan Mikes said:
I think the Grizl speed discrepancy might be caused by a wrong Wheel Circumference in the e-bike system.
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That’s exactly how my Juiced controller/display works. You set the wheel circumference in one of the menus. I assumed @Catalyzt had already looked into that, assuming it’s possible on that bike.
 
Stefan Mikes said:
Isn't the 840 a speedometer itself based on the GPS readouts? Why the redundancy?
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Because, in my experience over many years owning a Garmin device, the hub sensor is a lot more accurate than GPS. I've always used a hub sensor because of this. Now, the 840 uses a more modern set of satellites than the ones in my past, so maybe the GPS speed is as accurate as a sensor. For now, I'm happy with going with what I know.
 
On a BES2 bike, changing the wheel diameter in the display settings only affects the displayed speed and has no affect on the assist cutoff speed. The dealer can further change it, but to do anything that potentially changes the cutoff the mfgr has to get involved. I would be very surprised if things are any different with BES3.
 
BlackHand said:
On a BES2 bike, changing the wheel diameter in the display settings only affects the displayed speed and has no affect on the assist cutoff speed. The dealer can further change it, but to do anything that potentially changes the cutoff the mfgr has to get involved. I would be very surprised if things are any different with BES3.
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However it was done, Anna could ride her Flyer at 25 km/h today while her actual max assist speed was some 22 km/h last year.
 
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