The Inaugural Electric Bicycle Race

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Different strokes for different folks. I've got nothing against high speed at all. But I'm not convinced that most people would get an electric bike for that. They'd get a regular motorbike. Or just ride downhill.

I do agree that cycling is dominated by fitness freaks. Especially in my town, which is very hilly, and punishing for cyclists who don't have assistance. The other main demographic is children, who aren't allowed to ride anything else. Children get the idea of the e-bike instantly. They all want one because it goes to exactly what they use a bike for - suburban travel.

None of which is to say that if there were some good racing events for electrics that a new class of speed freaks might not emerge. Someone's got to set the trend.

 

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Someone's got to set the trend.

This is where I come in...

At present there is no product that is available for purchase that would satisfy the letter of the law (though violate the intent) which performs at a level that would allow "sport riding".

The number one reason the existing bicycles are all wrong for speed is that they have very short wheelbases. My road racers have wheelbases of about 52". A typical bicycle is about a foot shorter and that shortness means that they become unstable at about 30-40 mph. I've gone 60 mph on one of my bikes and it was absolutely smooth at that speed. (and I'm not just saying that to brag about it, it's a very real thing that I was focused on making true for my bike)

A 52" wheelbase is a necessary element in the design of a fast bike for the same reason that long ski's are used for the downhill events, you would not want to use short ski's on a downhill. (they would be scary and unstable)

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Anyway... it's a "chicken or the egg" problem. The electric bicycle road racing that is speed oriented will not develop without the base bikes and so until that changes you might as well focus on the marathons because the bikes aren't built for road racing right now. (at least if you are using public roads)

I'm thinking years down the road... what might electric bicycles be able to do? Where do people tend to ride? (suburban streets for the most part) The electric bicycle should be able to keep up with traffic in the suburban streets. (so about 30 mph average is about right) The typical bike trip would be about 10 miles which might mean a trip to the store or just around the neighborhood.

Go-Kart tracks seem the perfect place to hold the races because the track lengths and curves tend to resemble the suburban streets that the electric bicycle road racer would be designed for.

http://www.oldguy.us/blog/images/AerialMed.jpg
http://www.ballerhouse.com/wp-content/uploads/2008/02/go-kart41.jpg
http://www.wannerookarthire.com.au/images/kart_track1.jpg
http://www.aerialphotographerkent.com/images/large/lydd-go-kart-track.jpg
http://www.jacksonspointvillage.com/imgbody/3-S-Go-Karts-Track.jpg
http://www.oldpueblomiataclub.com/2008 Event Files/p1_kart_track_files/image002.jpg
http://www.nauvoofun.com/images/track.jpg
http://www.playozzys.com/attraction_go_karts.JPG
http://2.bp.blogspot.com/_hFvTUKoc_...s4/s400/1+14+2008+guyana+go+cart+track+4+.jpg
http://www.so-calsprinters.com/adamsphoto01a.jpg
http://static.panoramio.com/photos/original/11448181.jpg

etc... (there are go kart tracks all over the place)

Insurance is going to be much easier to get for a go kart track because they already have the safety issues resolved. Racing on public roads is filled with hidden dangers. Every object on the side of the road can cause injury if you smash into it. With actual racetracks they have grass or some kind of safety barrior in case you go off track.

This is a go kart track in New Zealand:

(it looks like a perfect place to hold an ebike race)

http://www.hirekart.com/gokart_hire.html

More New Zealand tracks can be found here:

http://www.kartsport.co.nz/tracks.html
http://203.167.191.27/sites/default/files/node_images/track photo 3.jpg
http://www.rotoruakartsport.co.nz/webseal3.jpg

 

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Years down the road? Who knows? My money is on a steady improvement in battery technology, smaller, more powerful, faster charging, cheaper. Where that takes the consumer and racer versions of electric vehicles is hard to know.

 

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Motor Power Limits Would Stand The Test Of Time

Just thinking about the way technology changes over time. It's very possible that with advances in battery technology that the battery no longer becomes such a bottleneck as far as ebike range. In the future maybe people no longer have to worry about having enough battery to get around. If that's the case, then having a race built around a scarce resource (batteries) would no longer make any sense at all. People would be saying:

"This is stupid... my ebikes battery holds ten times this much energy, why the heck are the race rules limiting me to this small energy amount?"

...if they increase the battery energy limits to accommodate the improving batteries then all of a sudden the ebikes are going to be able to expend as much power as the electric motorcycle racers.

The clarity of what defines an ebike disappears...

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In contrast, if the rules limit peak motor (input) power then no matter what happens over time with the rest of the technology the basic machines aren't going to change all that much. Even if someone invents a new motor that is nearly 100% efficient it's not going to be that different than the 80% - 90% efficient motors we have now. (enough so that the newer bikes win, but not a dramatic difference)

Anyway... that's another argument in favor of motor power limiting rules... they will last forever and not need changing.

1000 Watts input should be the worldwide ebike racing power standard. (it's a nice clean and round number) Even in countries where that's above the normal ebike laws they can do whatever they want on the racetracks. If the go kart tracks become the place that the racing takes place then the 1000 watts isn't going to be illegal.

A worldwide standard would be nice.

 

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Batteries have still got a looong way to go before they're in the ballpark of petrol. One litre of petrol will get a bicycle 60km or more, and that's delivering a few horsepower. How far will one kilo of batteries get you at, say 2000W? The energy density of petrol is 46.4 MJ/kg whereas a LiPo battery is about 0.72 MJ/kg for a really good one. OK, an ICE is only about 20% efficient compared to about 95% for a good electric motor, but still, that's 46.4 x 20% / 0.72 x 95% = 13.6 times more energy for the weight. And when it's used up it weighs nothing, so the vehicle gets progressively lighter and more efficient. A tank can be filled in a minute.

But batteries have been getting better and better at a promising rate. Maybe we'll get to the point you are hoping for, where they compete at the same level as ICEs. Currently, what they're really good for is cheap, clean energy at limited range, so squeezing more and more out of an energy limit is something that people are going to want to see. More speed and more range. It's competing on the very thing the technology is good for.

But I tend to agree, battery limits aren't going to make for an exciting race. Power limits make a lot more sense, and will impose battery limits all by themselves. You'll pick the exact battery size that will get you to the end of the race - any more is a waste of weight. That way the emphasis will be on getting the lightest possible battery for the Wh. And the thing is, everyone knows you can make an electric more powerful. It's not rocket science. The rocket science is still in the batteries, and how to make the bike lighter. The motors are pretty old established science - I've seen a book on rewinding motors that's about a hundred years old.

The cyclist adds a whole new element, since it's not just skill, but also their basic cycling power that counts. That's going to differ from individual to individual and from season to season.

 

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What It Would Take To Win

Weight isn't that important on ebikes.

In a power limited race the keys to victory (I think) would be:

Rider Skill 1 (ability to push the limits of traction)

Rider Skill 2 (knowledge of drafting)

Rider Skill 3 (knowing how to get past other riders)

Good Tires (sticky wider road race tires give more grip)

Better Aerodynamics (above 30 mph this is what matters)

...the motors being limited would produce very similiar power levels (no big advantage possible there) and everyone is going to use about the same battery so the weights would be about the same.

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The winner should be mostly based on being a better rider and not the bike.

Motor power limits favor certain types of rider skills over others. (there's no thinking about conserving energy when the motor power is limited already so you are usually using full throttle or nothing)

The motor can deliver about 1000 watts * 80% = 800 watts of power.

The rider can deliver (by pedaling) about 400 watts of power.

...so the bike delivers 2/3 of the power possible and the rider delivers 1/3.

Fitness is not so critical in ebike racing compared to skill... or shouldn't be... a weaker rider with more skill should be able to win against a stronger rider without skill. (have both and you get to be the champ)

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Evolution of the Battery

As batteries improve in storage capacity and lowered weight the track lengths could be increased to match. By keeping the motor power a constant the track promoters just need to do the math and make sure that the two things make sense. In todays battery technology the correct length for a sprint type ebike race is 20 km. Maybe in the future that might grow to 50 km... but we would just wait for that. As the battery improves the tracks get longer...

 

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I can't see weight ever not being a factor. It is in every other motorsport, and also horse racing. It goes to acceleration and cornering. Also, rider power will matter a lot - 1/3 is a substantial fraction. Aerodynamics and rolling drag will be big factors, so you could end up with biscuit thin tyres, and silly looking hats.

I expect all angles will be tried in the early days and the winners will quickly be emulated.

Either the tracks get longer, or the engines get more powerful. Why suck on only one horsepower, if you can have two?

 

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Why One Horsepower?

Because a human can for a short time equal one horsepower of energy. So the ebike definition should reflect that you are only able to have one professional athelete as "assistance" for your bike.

If you allowed more than one horsepower then you start to make human power a non-factor.

Think in terms of percentages:

250 watts motor vs 750 watts human = 25% and 75% (mostly human)

750 watts motor vs 750 watts human = 50% and 50% (the US ebike limit)

1500 watts motor vs 750 watts human = 66% and 33%

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And don't forget that on longer rides a human professional racer can only provide about 400 watts (we'll say 500 watts) so those numbers become:

250 watts motor vs 500 watts human = 33% and 66% (mostly human)

750 watts motor vs 500 watts human = 60% and 40% (the US ebike limit)

1500 watts motor vs 500 watts human = 75% and 25%

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Which means that at two horsepower the human power is from 25% to 33%.

I think the "50% and 50%" is a good general rule (750 watt limit) because it allows the motor to be big enough to let you know it's there without completely dominating the bike.

Ebike needs to mean something... I think they got it right.

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One thing... if you run the math on all this you'll find that with a one horsepower motor it's actually FASTER to get behind a fairing and stay in a tight tuck (because your frontal area is reduced) than to be stretched out like on a normal upright bike. They've compared recumbents to "tight tuck" areodynamics and they are fairly close with a slight edge to the recumbents. Road racer (upright, but in a tucked posture) bikes like mine can go fast and also TURN fast. The recumbent are really poor in the handling department because they are nearly impossible to slide without crashing. In the beginning I'd expect recumbent ebikes to attempt to compete, but after a few hardcore crashes I'd expect that they fade out or go off into one of those endurance marathon things with battery limits. When it comes to the "real racing" (my definition) on something like a go kart track the Electric Bicycle Road Racer (EBRR) should dominate easily.

At least that's the plan. :helmet:

 

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there's a reason the standard sit-on bike was originally called the 'Safety bike', and that most motorbikes built on that configuration. Not to mention that sitting up is comfortable. Personally, I sit bolt upright, because I'm not usually going fast enough for wind-drag to be an issue, and I like having a healthy spine. For me, riding is about cruising around comfortably looking at stuff, whilst getting moderate exercise. I don't fall into the hardcore exercise cycling camp who couldn't see any point at all to an electric, nor the hardcore speed-demon camp for whom the pedals are really just to limp home with if the engine breaks down. Which most likely puts me out of any racing camp, period.

 

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I think you have correctly identified one of the strange social issues that has cropped up with ebikes. The people that get into them (now) do so for a variety of reasons which include:

Political Correctness, Global Warming, other Causes ("The Goode Family")
Old Age, Poor Physical Condition, Disabilities
Nerdiness, Techno obsessed
Adventure in a new Sport (my case)

Actually I fit some of all the categories except I am a conservative who sees the eventual end of oil as something to work around.

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When it comes to "racing" it seems like a lot of the people that are getting into ebikes at present don't really understand what racing really means. There seems to be a desire for "easy" racing... which is a contradiction in terms. Racing always gets serious after awhile (like everything in life) and the folks that want "easy fun" tend to fade away. In the end you get people who are hardcore in whatever happens to be at issue.

So we have a long way to go. At this stage the "vision" is still being formed about what an electric bike might do, how it might relate to people in the environment that they live in and how they might best be able to race them.

Eventually there will likely be the "tours" and the "sprints" just like in regular bicycle racing.

Almost all the people interested in ebikes now will be out of the game after a few years as a whole new crop of people (with different attitudes) will come in and take the positions. It's just like everything in life... the "pioneers" are a different breed of people than the mainstream people which follow.