Maximizing range for supermoto

[Theo]

After @Johnny Depp's Maximizing Range for the Stark Varg, here is a supermoto edition.
When talking about maximizing the range of the Varg, personally I never mentioned changes to its aerodynamics because most of the users of this forum, including me, use it as a dirtbike.
Now there is an official supermoto version and some people have converted MXs or EXs. In a situation like this one I bet that if the same battery and powertrain were used in a sportsbike, those 40 miles wouldn't be a problem; the average slope for 4,000 ft is small and you can still save/regen a bit when downhill.
When a manufacturer wants to maximize range, they will take a lot of care of aerodynamics; the Mercedes Vision EQXX is an example of this, with its 0.17 Cx.
In general, the aerodynamic drag is the major energy dissipator past low speeds; it grows so much faster than the rest of the drags that you can basically say that if your top speed is for example 100 mph with a 30 HP bike, than it means that you need roughly 30 HP just to win the air drag with that particular bike at that speed. If you get some typical Cx values for motorcycles, you'll find out that this realistic experiment matches the formula.
The Cx values I've found online and in books change significantly with a leaning forward rider, so first of all, I'd like to see some testing done with a rider leaning forward vs upright and I expect to see differences.
One thing that I read in a laymem friendly scientific journal years ago was that vortices generated by the wheels are really detrimental for aerodynamic efficiency especially because in a wheel:
• the bottom part in contact with the asphalt is still, even when you are doing 200 mph (actually there is a percentage of slippage: it's almost still)
• the hub moves at the same speed of the vehicle
• the top part moves at twice the speed of the vehicle! If you are doing 50 mph with your Varg, then the top part of your wheels are moving at 100!
Still in that article, they explained that when they tested fairings on wheels in F1 they noticed quite some gains in top speed, like 15 mph. They then went back to open wheels because of a matter of rules and not because they think they are better.
If someone made a front wheel fairing for the Varg covering it close to it, I'd be curious to see whether that would improve the range.

 

[Erwin P]

The best thing you can do is add a massive windscreen.

I have seen significant range gains on my Zero DS even with a small windscreen. A E Motorcycle shop has seen E bikes with windscreen getting way more range than naked bikes. Hell even the way taller Experia go better range than it's naked counterpart.

Bikes are quite aerodynamic. Those meatbags on top are not.
Get yourself some bolt on screen and have a go.

I have a mini fairing rally tower thing for my Beta 300. If you bolt on that and add a big windscreen instead of that tiny thing i bet you will get some decent results. I would start with a huge unit and trim it until the wind goes just around your shoulders and just over your head.
You want that meatbag inside an air bubble.

 

[Caryder]

Take your cues from MotoGP. The only motorcycles more slippery are on the salt flats, and nobody is going to commute in a streamliner. For the street, a low front fender, fairings around the forks, and a small windscreen can do quite a bit.

 

[Bodo]

An interesting factor for range on tarmac is recuperation; or rather the lack of. The amount of energy won back with recuperation is so tiny that it kills more kinetic energy by deceleration in most situations driving overland. I remember a yt video where a Zero owner towed his bike's rear wheel with a pick up for a couple of hours on full regen and only got a couple of % charged into the battery.

On a b-road where you can effectively drive with a lot of foresight, coasting through most decelerations lets you save more energy by not using the accelerator than recuperation can win back.

I tested regen on my Zero after driving up the Stelvio on the way down - the calculated expected remaining range in the display went up very fast, but not because the amount of regen energy was so high, but because it used almost no energy downhill than compared to uphill where I spanked the bike into heat de-rating a couple of times.

 

[Theo]

An interesting factor for range on tarmac is recuperation; or rather the lack of. The amount of energy won back with recuperation is so tiny that it kills more kinetic energy by deceleration in most situations driving overland. I remember a yt video where a Zero owner towed his bike's rear wheel with a pick up for a couple of hours on full regen and only got a couple of % charged into the battery.

On a b-road where you can effectively drive with a lot of foresight, coasting through most decelerations lets you save more energy by not using the accelerator than recuperation can win back.

I tested regen on my Zero after driving up the Stelvio on the way down - the calculated expected remaining range in the display went up very fast, but not because the amount of regen energy was so high, but because it used almost no energy downhill than compared to uphill where I spanked the bike into heat de-rating a couple of times.

IMO the problem is that the regen braking only works with the rear wheel and we all know how little stopping power the rear wheel can deliver before starting to slip. Front brakes of street bikes, vice versa, are pretty powerful; I've read estimates like hundreds of kW and it's not so hard to believe if you consider the typical decelerations those bikes are capable of and do some maths. If we could recuperate from the front wheel, we would get something way more significant IMO.

 

[Erwin P]

That's the good thing about Starks. You can switch between regen maps. Long downhills in the mountains can take 100% regen while you go back to something like 40% on flat.
Not that it matters in my home country. But in places in France and Spain i've seen some nice added ''free'' energy coming of hills.