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[Hans2183]

It might just heat up or otherwise put strain on components too much.

Or maybe they want to sell a sport plus mode in the future.

[didierm]

Well, looking at ancient dinosaur burners from a previous age, it hurts to see a BMW K1200R  (never ridden one, the SR/F is my second bike, after the DSR) whizz past a top tech electric MC at 2.8s ...
It simply doesn't feel right ...

(and the SR/F is a slouch between 0 and 30 km/h, IMO).

[TheRan]

I wonder if the SR/F has low speed torque limiting like the other models. If it hasn't and a full throttle launch with traction control off doesn't spin the tyre then you could change the gearing for faster acceleration. One thing many people don't realise is a lot of gas bikes actually have more peak torque in first gear than most electric bikes, so if you can get the revs up and launch it well it's no surprise they'll get to 60 quicker. The real advantage of electric bikes is rolling pulls when the gas bike would be in a higher gear and/or at lower revs.

[didierm]

Thanks for your explanation.
Still happy with the SR/F ... (but that 0-30 ... )

[remmie]

At the traffic light an ICE bike is normally just idling.

If they would do the 0-60mph / 0-100kph measurement from red to green light and mandatory idling for an ICE i'm sure the SR/F and SR/S would win it almost every time.

regarding the comment of ICE bikes having more peak torque in first gear i can provide some calculations i have done when i got my first Zero SR and adjusted for the SR/F

The SR/F and SR/S produce 190 NM at the motor, the final drive ratio is 4.5 (90/20 teeth) so the torque to the wheel is 855 Nm. The wheel radius is 314 mm (thereabout) so torque to the tarmac is 2720 Newton.
Weighing 230 kg + 80 kg rider => theoretical acceleration = 8.4 m/s^2 or around 0.9g
0-100 kph (27.8 m/s) would take 3.1 seconds minimum (NOT accounting for wind resistance, reaction time, torque limiting etc etc)

Now for comparison a 2010 Triumph street triple 675 cc (because i owned 1 and it has a rather flat torque curve)
max torque is 69 Nm. But the total gear ratio in 1st is 14.2 (1.85*2.62*2.94) so the torque to wheel is 980 NM (125 NM more than the SR/F!!)  The wheel radius is exactly the same (both 180/55/17 wheels) so the torque to the tarmac is 3120 Newton. Much more than the SR/F. The street triple also weighs less (189 kg) so the theoretical acceleration is 11.6 m/s^2 or around 1.2g. The theoretical 0-100kph time would be 2.4 seconds. Obviously time is lost for revving through the range and fiddling the clutch.

Now if you would use figures of a more modern ICE bike the Newton to the tarmac are be even higher.
Ducati Panigale V4 2020 :124 Nm, 198 kg wet 1.8*38/14*41/16=12.5 => 1552 Nm to the wheel (almost TWICE the SR/F)

Easiest solution for an SR/F to gain 0-100 kph time is a larger belt drive ratio. So either a larger rear sprocket and/or a smaller front sprocket (and a stronger belt ) An 18 teeth front sprocket would yield a 10% increase in torque to the tarmac, and would probably fit with the standard belt using the standard belt tensioners. Topspeed would obviously suffer as well, restricting it to "only" 180 kph. It would probably have a (negative) impact on belt life as well due to the tighter radius at the front sprocket and the added strain in the belt.

[didierm]

Thank you for the sound mathematical rationale, remmie ; what a great forum this is.

I'll leave sprocket exchanges to the mechanically inclined (everything beyond 12V ⁽¹⁾ puts me in life danger), and put all my hopes on clutch fiddlers to defend the Zero colours.


⁽¹⁾ (OK, that's electricity, not mechanics, the latter which would put me even more solidly in Jackass ⁽²⁾ territory)
⁽²⁾ https://en.wikipedia.org/wiki/Jackass_(franchise)