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[TheRan]

By fitting a fairly simple duct they're reduced drag by 10%, resulting in a 7-9% increase in range. Pretty neat, if the space is there then there's not much downside to it. Could do with a full fender at the rear though.




https://www.motorcyclenews.com/news/2024/november/white-motorcycle-concepts-zero-motorcycles-sr-s/

[princec]

Wow! That is seriously impressive, if it meets its claims.

Cas

[Zelidar]

It is worth trying. In comparison of my SR/F, I still don't fully understand why my Tesla M3SR+ which is 6 times heavier and has four large wheels only requires 1.7 times the energy per km.

[shayan]

Ver interesting! But, do the air ducts go around the chargers? Its not very clear from all the photos

[JaimeC]

It is worth trying. In comparison of my SR/F, I still don't fully understand why my Tesla M3SR+ which is 6 times heavier and has four large wheels only requires 1.7 times the energy per km.

One word: Aerodynamics

[mdjak1]

Somewhere I heard the term "meat flag" used for the motorcycle rider.   While these little ducts might reduce the drag of the motorcycle itself by 10% (ignoring whether they are even possible given the position of the charger above the battery), you would need to put some serious holes in the meat flag sitting on top of the bike.   And if the meat flag isn't in a tuck position (such as on the DSR/X), the aerodynamic drag is even worse.

[2020_SRS_Commuter]

LOL the pic of the duct and pack shows you would be sitting about a foot higher.
Is this their plan? Lift your ass up so you are laying flat? That might increase aerodynamics.
In their picture of the whole bike the duct would pass through the majority of the seat subframe metal structure, and there is no place for the chargers, 12v battery, or fuse box.

It looks like there are two ducts, the left one exits low, the right high.



 

[TheRan]

I was curious about the chargers, my understanding was they're placed on top of the battery but the article only mentions relocating the "ECU". They also mention they modified the subframe, front and rear mudguards, and raised the seat height. I don't think they've raised it by that much though, with the ducts it looks about level with the kink in the tank where the charge port flap is where as stock it's maybe an inch lower than that.

[Fran K]

It is worth trying. In comparison of my SR/F, I still don't fully understand why my Tesla M3SR+ which is 6 times heavier and has four large wheels only requires 1.7 times the energy per km.

If that is accurate......     and it is off topic.....          Motorcycle tires are round in cross section where car and truck tires are flat on the bottom or outer edge.  Same reason the tires wear out faster, the center portion wants to cover more distance than a bit towards the edge.

[JaimeC]

The story behind the original photos posted above:
https://thepack.news/white-motorcycle-concepts-and-zero-motorcycles-reveal-intelligent-aero-technology-concept/

[shayan]

Ver interesting! But, do the air ducts go around the chargers? Its not very clear from all the photos

Found the answer from https://www.cycleworld.com/bikes/zero-and-white-motorcycle-concepts-intelligent-aero-prototype/:
There are two outlets rather than one simply because that front intake splits into a pair of ducts that channel the air around existing, immovable hardpoints that couldn’t be altered without changing the structure of the bike. The point is to show that the duct can help without the need to go to such extremes. To make space for it, some of the bike’s charging and control electronics have been repositioned above the duct, eating slightly into the storage locker on top of the “tank” area, and the seat has been raised a little—but it’s still at a manageable height and the front cubby remains big enough to keep your phone in. Testing so far has included computer fluid dynamics simulations and real-world tests using “aero-rake” sensor arrays to understand how the duct’s performance can be maximized within the constraints of the Zero SR/S’ shape and structure

[2020_SRS_Commuter]

Personally if this was a modification, I would not want it. And if they offered this modified zero for sale along side the original, I prefer the original.

#1 it puts your butt up in a semi-racing crouch, which I'm NOT doing.
#2 It raises the heavy charger(s), and other bits, as well as yourself, higher up so you have a higher center of gravity.
#3 Longer reach to the ground that some people may not be able to manage
#4 All this offers zero efficiency as a trade off, no pun intended, until you get to high enough speeds to make it wk.
#5 Does it still offer such high gains when you load the bike with side and top bags? I bet then its effect is negligible.
#6 Loss of much of front storage area. You also lose under seat storage too.
#7 No way to fit power or charge tank.

Sorry to be such a sour puss but something about this has my senses up, that its vaporware baloney. Maybe its just me. But... there are so many other factors that are so much more significant than a couple little ports through the body of the bike.
 
Did they actually say at what speed this efficiency occurs? How did they test it? 

[TheRan]

White has a bunch of records as well as having previously modified a Yamaha Tri-city into a petrol-electric hybrid, it's definitely legit. They say the gains were made under "regular riding conditions" so presumably sticking to the speed limit at 70mph and below.

[shayan]

And this is a prototype modification. If this were to go to production they surely should consider resolving the change in seat height, weight distribution etc. I really love the modified front fender though!

[flynnstig82r]

While this particular mod is probably not going to make sense for most SR/S owners, they seem like a legit venture and I’d love to see these ideas incorporated into a clean slate design. The CEO of WMC’s comments in The Pack’s article was spot on. Aero improvements are cheaper than a bigger battery, they help charging effectiveness along with range, and the improvement gets bigger at higher speeds where battery-electric efficiency struggles the most. The battery can be smaller, which means even more space for aero ducts. Unlike a streamliner fairing, I don’t see any reason why this duct would make a bike more susceptible to crosswinds, either. I’m taking the effectiveness claims at face value as a lay person, of course.