Motored Biking Racing in Arizona

[AussieSteve]

safe, what was the point of that post? You know that everyone will be doing more than 20 mph.

so, (thanks strotter) .....

O.K. back to the subject of this thread......

Everything is invited to race. Those that went last year, what is a good configuration to run and be competitive? Does a rack system on a beach cruiser have a chance? I know that is a subjective question. Does it have a chance at having fun? Yes, I'm sure it does. Does it have the ability to keep up and not get embarrassed? (that is the question behind the question)

Also, what are the accommodations like? Any camping facilities near by?

Among the ICE bikes, I'd imagine that those with well set up shift kits and pepped-up engines would stand the best chance, over a set distance.
Most of us would be out of the running. I have a 66cc w/ hi-comp head and shift-kit, but everything else is almost stock. I'd be left behind.
I'd love to hear last year's max speed, if anyone knows.

 

[happycheapskate]

Ebikes are fast. This should be neat. Can the ebikes switch batteries or do they only get to use one battery per race?

 

[AussieSteve]

G'day, HCS, I've heard no mention of pit-stops. I'd say one race, one battery pack.
Raises an interesting point - are pit-stops allowed?
(Probably not in such short races.)

Another slightly important point. What are the capacity / power limits, or is this open?

I think that along with all of our BS, SpookyTooth need to poke their head in and post the full rules somewhere.
If there are no size/power restrictions, it wouldn't be hard to wrap a frame and pedals around a 250cc dirt bike engine and leave everything for dead.

Just emailed SpookyTooth re rules & limits.

 

[safe]

So no one knows (exactly) what the tops speeds have been before?

The description of the track says 50 mph so maybe people are getting near that. Aerodynmically it gets really, really hard to go faster than 40 mph without several horsepower or having a slick aerodynamic package. Since all the bikes I've seen are without fairings the odds are they are tapping out at about 40-50 mph because a 50cc motor can get about 5-6 hp. (4500 watts for the electric) My old MB5 had about 5-6 hp and I could peak at about 50 mph and could run all day long with it.

The big problem for electric is that with a fixed battery supply you have to decide between speed or range. Electric bikes use simple math:

Total Battery Power = Range * Power

...so if you increase your power output you tend to reduce your range. This gets worse as you really push it at speed because the efficiency goes down and you end up pushing more wind which means more losses. The best efficiency (and therefore range) for an electric bike will occur down around 20 mph. For electric bikes to be able to really go fast the distance needs to be cut down to about 10 miles (10 laps) which is a Sprint compared to the "Death Race".

Anyway... I hope the sponsors can figure out something to accomodate the electric bikes and make them feel relevant to the "Death Race". However, from the description of the event it sounds more like riding around on my old MB5 where the goal is endurance.

I wonder how long last years race went?

 

[AussieSteve]

Those speed estimates are fairly accurate, safe.
I've clocked 83kph, (~52mph), on mine, but it needed a gradual down slope and light tail-wind.
Usually I can't get more than about 70kph, (40mph) on the flat and I only weigh a little under 50kg, (110lb).
In 6th on my bike, 83kph = 7500 RPM.
Having the power to actually rev that high on the flat is another thing.

 

[safe]

The Isle of Mann Example

http://en.wikipedia.org/wiki/2009_Isle_of_Man_TT

Superbike TT - 6 Laps

Sidecar TT - 3 Laps

Supersport Junior TT - 4 Laps

Superstock TT - 4 Laps

TTXGP - 1 Lap (electric motorcycle)

...so if we make comparisons to the Isle of Mann race then you have to figure that the distance needs to be rather short. Each lap of the Isle of Mann is 37.733 miles and that's the outer limit for electric motorcycles as far as range. Even at 37.733 miles the electric motorcycles were focused on carrying their speed because they were cutting it close to make the finish.

10 laps and 10 miles sounds like a reasonable distance for electric bike racing. More than that and it starts to favor increased efficiency techniques and that's going to make it dull. It's better to make a Sprint that is fast and furious than to drag it out to an endurance race for the electric. ICE bikes don't have this problem and can run flat out for 100 miles or more with no problem.

The "Death Race" will not be won by electric bikes, but a Sprint might...

 

[AussieSteve]

37 miles at a max speed of 106mph, (Robert Barber) and an average speed of 87mph.
I've got some footage of that race and the comments of the riders etc.
Not too shoddy.
They didn't mention battery capacity, power rating etc.

 

[safe]

There are no artificial limits imposed on anything on the electric motorcycles, so they basically push the bikes as fast as they can while using up their large and expensive battery capacities. 40 miles at full speed is about the maximum they can go. The problem with electric motorcycles isn't usually the peak horsepower. In fact, the top speed bike ran an Induction Motor which has a flatter and wider powerband than a permanent magnet motor. But the Agni bike used an Axial motor design which tends to be more efficient, so while the Induction Motor was stronger, the Axial was more efficient and that meant the batteries were used better.

For electric bike racing there have been various ways of trying to equalize competition such as limiting the battery capacity or the motor power or the battery voltage. For a short enough race where the main issue is traction (knee dragging through the turns) those issues about regulation are less important because the main focus is on rider skill. The central rule is that you must have operable pedals and that's the thing that separates the ebike from the electric motorcycle.

Later on I'd like to see power classes like 1K (1000W), 2K (2000W) or Constant Current. But that's waaaaaay into the future. For now the goal should be flat out wild and crazy racing for a short Sprint and the go kart tracks are the way to make that happen.

 

[azbill]

last years race saw speeds of 40mph, so yes, the track is 'fast'
the reason the races are now held at a closed track is so people CAN go faster and not worry about 'the man'

lots of arguing between you aussies here, are any of you making the big trip ???

 

[safe]

Hey, I'm a true blue American that can trace my family back to Samuel Adams on my mom's side and am German on my fathers side. AussieSteve and AussieJester (Kim) are the Australians.

That's why a page or two back I was "insinuating" that the Australians were trying to wreck an American race.

I live in Missouri now and have multiple reasons for not being able to make this event, but I've also been pushing the idea of Electric Bicycle Road Racing on go kart tracks for a few years. Politically I'm like my Samuel Adams ancestry and support the Tea Party Movement here in America. Go Sarah!

It's great to see my dream of racing on go kart tracks a reality. (in my lifetime) It looks to be a real winning event (again) and all I can do to help promote it online I will. I've posted information about the "Death Race" on a couple other forums to spread the word.

Love to see that these races are taking place... for real !!!