E-bikes running with the Gas-bikes

SoSauty

1 kW
Joined
Mar 17, 2009
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339
While browsing the HobbyKing Turnigy motors, noticed that the 80-100 was compared to 80cc gas. And what struck me was the 80-100 could give some value with 8 & 0 as the 1st 2 digits.
https://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=5142
After talking with a few other bike builders and noticing the differences between outrunners (Turnigy) and inrunners (Astros), it seems that the length X diameter size is a more accurate indicater of "potential" power than mass/weight. The Astros are heavier, yet the Turnigys are torqueyer. Also, this measure makes for a nice comparison to 2 stroke bike kit motors.

Using this concept:
Turnigy80-85, 80 X 85 = 6800 or 68 rounded up to 70,
Astro 3220, 3.2 X 3.4" or 81mm X 86mm = around 70,

Check the motors below; the solid black anodized motor is an Astro 3210:
View attachment 1
It's 56mm long X 80mm dia. = 44.6 or about 45, and more/less performance in the ballpark of 45cc 2 stroke bikes.

One other motor measure lends to this concept:
The Turnigy Max50, just under 63mm X 80mm which rounded equals 5000. Its' label states 50cc. Kinda easy to deal with.
Max50Turnigy.jpg
I've been thinking of ways to classify e-motors. Karting, quads, motorcycle racing all use cc (and shifter) to designate racing categories. What easy methods/units can be used to specify e-power motor potential relating to RC powered bikes :?:
 
I would say it's as much the power of the bike as the skill of the rider in many ways, but you could roughly categorize them by wattage (estimated) to the rear wheel.

With E-Bike racing being relatively new, I would think dividing them up into much more than 2 or 3 power classes wouldn't be practical, until there are more riders, but I'd prefer the "unlimited" to have their own race VS having everything in one race with such mis-matched power & rider skills.

Maybe there could be some form of "qualifying" and match riders by lap times, i.e. slower lap times in one, higher in another.
 
What you are talking about is power potential, not actual used power. I think the power used should be the determining factor. It is a lot easier to check power used with an ebike compared to a gas bike (if you don't have a track side dyno.) I think to say that a motor is a 20hp motor just because of it's size, even if the bike is delivering 10hp of power is the wrong way to go.
 
I am not quite clear on your "power used" phrase there Jay64. please clarify peak vs continuos...we'll start from there.

Right now, I think we need a few Agni powerd super bicycles. If for nothing else, just for the demonstraition factor & to compete on level ground with the insane 200+cc CVT equiped motored bike builds showing up.

Measuring the total out side physical dimensions of an electric motor is a bit wonky though.
Its the stator size & amount of copper inside that combine to make the energy transfer from ellectrons to rotaion.

After that, its topology steping in to determine the motors tourque constants & cooling potentials to factor continuous ratings. This means that a large outrunner will dominat an small inrunner of in a certain set of prameters & the outcome completely oposite in another senario. which is better? it all depends....

I suspect the Golden motor wouldn't even flinch when loaded to the levels that would destroy either Turnigy or Astro on a dyno.(but no one races a dyno around my neck of the woods)

Back to the OP question.
We have seen that the perfect power delivery of Electric motors will crush a chinees 2-stroke kit & more than match a morini powered bike with single gearing & an adjustable clutch with a 6kwpeak & prolly a 3.5kw avarage ( :?: )

I think we need more builds using the price attractive components & start winning some converts to the E-racing scene.
its a shame the big Clyte motors are no more....farfles build would really apeal to the masses for a track bike.
 
I would think peak watts achievable at the wheel would be a good way to classify race categories. That is not the watt rating on the motor. I run a 1000w motor and regularly see 4500w from it. It would have to be what it is capable of putting out. Similarly, you can buy a 10hp gas engine and tune it or change components to get a higher hp out of it.

Just because a gas engine is capable of 11hp, that doesn't mean it makes that all the time. It is only doing that accelerating out of corners or down the straight. Just like an electric is only making peak watts during hard acceleration.

Gas engine power can be measured in kilowatts and is in many parts of the world, so convert the gas hp to watts to compare. Just my 2 cents and I'm sure I'll be told if I am way off.

Clay
 
Thud said:
Its the stator size & amount of copper inside that combine to make the energy transfer from ellectrons to rotaion.
Yep, not exactly "easy", but I rekon the best way to class motors is by copper fill.

mm^3 of copper are to electric motors kinda what CCs are to ICEs.

How you use the copper is the name of the game.
 
TylerDurden said:
Thud said:
Its the stator size & amount of copper inside that combine to make the energy transfer from ellectrons to rotaion.
Yep, not exactly "easy", but I rekon the best way to class motors is by copper fill.

mm^3 of copper are to electric motors kinda what CCs are to ICEs.

How you use the copper is the name of the game.

I disagree. An X5 has several if not many times more copper than the winning RC motor, but probably less power.

I think the best way to classify is by power in. Then we just need easily programmable and accurate circuit breakers that will trip if the power limit from the battery is exceeded. Come up with a standard plug for everyone to use, and it's the builder's responsibility to properly class his own bike. That's the future anyway. In the meantime, strap the bike down to a heavy wheel, and measure max current under load with a clamping ammeter and voltage.
 
Copper fill would be ideal, but you need something easy to measure or it won't work. Power out of the pack is the easy way. If you have an inefficient system, tough.
 
we are a few short posts away from a 1000 watt race :mrgreen:
we need to be carful in definitions...just because a motor will draw 10kw of power through a controller is no indication of its power output. Luke proverd it a few times melting a few dollars worth of motors on a dyno feeding them more than they can swallow.

Johns example is a good one. a motor with maybe 3x as much copper & almost 8x the total mass, constrained by direct drive, can not deliver the "power output" of a lightweight motor spinning 10krpms with proper gearing.... all things being equil the motor that optomises power density will have an advantage some where on the track.

whats the answer? I don't like the idea of limiting controllers....I don't object to buying a perm & building on that....but is it nessisary? I have lots of fun at 5hp on a kart track....but would really enjoy the challange of trying to tame twice that in a racing senario. My twin turnigy builds have deliverd some real performance (still not enough to over power a good set of tires on a set up race frame like luke displayed) & the 1/2 mile i have on the 4" CA120 has me very interested in further tesing with this motor....but really, whats the answer? a spec motor & spec tires with spec batteries to let everyone feel they are on even terms regarding equipment? bahh

I will just build to run with the auto clutched morini's & have me some real fun hanging at the track. if I have to build to compete with a 20hp full on Kart motor with a CVT thats another discusion altogether.
 
Until there are track dyno checks and mandatory tear downs you guys are just talking silly chit.

I say just call it ....

slow, med. or fast and the owners decide.

We electric bois are ahead of the curve. I figure we should be graceful about dominating. Need to suck more of them in. :mrgreen: :mrgreen:
 
I agree with nicobie, rate the riders not the bikes, theres already heat races
make them qualifying for the main, break the times down slow medium and fast
3 sperate classes should be plenty...jm2cw

KiM

p.s i would agree on a capped power level at some point, i think Safe actually had a good idea with the
power cap, but not at 1000watt...i think a max of 8kw would be more than enough to have great fun on a kart track IMHO
anymore is just 'pit posing' value, and starting to head into small motorbike territory, keep these things
at least resembling a bicycle, not a motorcycle with token pedals ...
 
True, it's all friendly now and no one is sand bagging, so there is no problem to address. I think if Luke had geared for 45mph top speed that he would have beaten the 20hp bike at his own game. Plus Luke's heat problems probably would have been out the window too.

What do you racing knowledgeable guys think about the difference in setup required for the La Grange track vs the track in AZ used for the Death races?
 
Comparing to ICE engine CC sizes is pointless.
ICE Bike and Kart racers have argued over how to classify motors for years..and continue to this day.
Simple cc ratings do not work ( unless you have the $$$'s to buy into this weeks fastest motor club) OK for F1, Moto GP etc.
Output measurements ( power or torque) are not effective ( too many ways to "fudge" a dyno run)
The most effective way found so far is to run "Spec" or single make motor classes, but even then you have to agree to run "unlimited modifications" , or have the tech skills and resources to inspect for compliance to the rules.

The best solution is to run a "Bracket Racing" system where you can race anything ( providing its considered safe) but you are classified by your qualifying time.
I assume most racers understand the "bracket" racing concept ?

The problem with an "open" or RWYB race is that it rapidly becomes "cheque book" racing . :cry:
 
I agree, but it takes a lot of expensive track time and manpower to get lap times on everybody. But a drag race down the main straight could be used to sort out the really fast guys quick. Or maybe run 9 bike, one lap heats. First 3 group a, second three group b, last three group c. then race each group in a heat. Top finshers from each heat go into a main event, but only the top two from the slower groups.

Yer bike has a problem during the 1 lap heat, tough titties, but maybe you trophy your group if you fix it. Nobody's really going to sandbag, they want to race in the man group.

Much simpler though, to just ask the racers to assign themselves to a bracket. We all know, or can find out in practice laps what our top speed down the straight is. 40 mph club, this way please. You wanna race your 35 mph bike in the 40 mph club? your funeral buddy, but let em pass you. You can still have a few heats where all run together just for the fun of it. Then do three brackets of main event.

It's just too much work to actually sort out the bikes as the race organizer. But a rider could chose his bracket easily. Then you don't have to have 6 different classes of main event. Most of us will be quite happy to stay in a 35 mph bracket forever, leaving the checkbook racing to the 40 mph club bracket. This started out as a poor mans sport, and most of us will remain too poor for checkbook racing. So we'll be happy with a middle speed bracket.
 
Surprised nobody's suggested battery energy. If you have a 1hr race, and 10s 15Ah then you have average 38*15watts, 570W.
This is simple to police and fosters efficiency and regen.
In my experience the Lipos (which everyone uses) supply pretty much exactly what they say on the package....
 
Neat, ideas all over the board. Some point out a distinction 'tween hubbies and RCs. A batt pack efficiency run gets alluded to. Others address what about the gassers? Let's see, copper fill, valid in motor theory. Wonder if anyone knows if applying copper/iron mass for outrunner/inrunners is apples/apples or apples/oranges? There's power in, power out, 'an power at the wheel.

Surprising support for, who gives a crap bracketing. Race1, those whose dignity lies in the 20mph club, race2 30mph club, race3 40+ club. Of the 45 bikes radared at Grange: 11<30mph 20 in 30's 14>40mph or just slow, medium, 'an fast.
Of course, there's a formal type of bracketing which I take to mean lap times.

Also a humble remark, let's welcome folks to the e-life, not try to dominate 'em. AJ, you make me want spend my vacation dollars in the land of boomerangs, ">8K Pit Posers" :lol: Tickles my funny bone though I mean no disrespect the manspeed innovators.

What about the present separate but equal racing? Whose gonna howl at blending the e-s and the gassers, and why?
 
I think the gas and electric should run together. At one point I liked the idea of an electric heat, just for the reason it implied more that one ebike there.

Dumb as it is, I still somewhat like the idea of a "stock class" when ebikes become more common at the race. Bring a "36v" battery, and a bicycle hubmotor. Obviously somebody serious will bring a 100 amp controller, etc and slay the field. But the rest will be racing some very similar speed bikes, making for some fun trying to pass each other at 25 mph.

Then of course, you can still race your real bike in the 40 mph club class.
 
"That would work for ebikes. But what about the gassers, limit their gasoline?"

mwahaha yeah - give them the same amount of energy to last the race (what was it? 0.54kWh? - I think that's about a teaspoon of petrol isn't it?) - that would bring home the difference between 90% efficiency and 10%........

seriously though I was just suggesting a way to implement "classes" in an ebike race. However I have always thought a fuel limit was the way to regulate motorsport - the old excuse that "racing improves the breed" would actually happen then. e.g. Formula 1 has 20 gallons of 4star for the race, formula 2 just 15 gallons etc. right down the line
 
One problem with having fast, faster, fastest groups (names used at track days to not make the slow group feel bad :mrgreen: ) run in heat races, and then the top guys from each group race in a final race is that the fastest guy from the low group will be in the final but someone who was, say 4th, in the top group won't be in the final. Even though his lap times might have been way faster than the people from the other groups who made it in. I would feel pretty bummed if I didn't make it into an even and there where about 5 people that did make it in the main that were significantly slower than me.
Also, copper fill/motor potential, doesn't really relate to what is actually being used. If you don't have the battery pack/controller to use it to its full potential than I don't think the bike should be rated for the full potential. An example of that would be at the Grange race where people were running 215cc 4 stroke motors in the <11hp class. Those motors definitely had a potential for much greater hp, but apparently weren't built to that point.
 
You cannot race "Stock" classes unless you have tech resources at the track ( dyno, tools, skills, and knowledge) to verify the motor, battery, controller specs.
...Near impossible for electric kit i think !
Limiting "fuel" or battery capacity is much like the above with the added complication of turning it into a technology / efficiency competition which means its a $$$ competition again, searching for the ultimate motor & controller etc.
Bracket racing has been shown to provide the best competition with the least technical restrictions.
Establishing bracket times is a well known process using heat races.
Final run offs between individual "bracket winners" can be done using a "time" handicap final race.
 
The new thread title put a picture in my mind that I just can't shake. That is SoSauty pouring gas on his batteries before making that reverse polarity connection. :mrgreen:

:idea: That reminds me of something we need to start doing. Every battery fire clip or pic should be edited to include video or pics of what gasoline can and does do. We aren't doing the movement any favors at all posting the battery fires everyone loves to watch, but we can flip that around to show how they're safer than gas and get to see even better fireworks.
 
Thanks John, aside from a fun new nickname "Smoke" there's a serious side to this. I'm TIGging up some alumium batt boxes, my conveyor belt boxes were fire resistant but did burn and smoke. If aluminum boxes were used, open only on 1 end, that fire wouldn't have risen 6-8ft or whatever. The rubber smoke was horrific as well. Nevermore spoke the Raven.

Back to our topic. Super simple 20mph, 30mph, and 40mph class. You speed 30mph in the 20mph class and that bike/rider gets a reclassified into the faster 30mph class.

Look at this radar gun link:
http://www.radarguns.com/bushnell-radar-guns-101911.html#
 
I actually think a 1000w race class would be alot of fun. It would force the builder to consider the pedals as a usable implement instead of an annoying impediment. I think PaulD is probably going to win this class too as he rides a fair bit more than I do, accept while he is stuck in Oregon knee deep in snow, I'm still out riding. :lol: I would probably go friction drive on a steel road bike. This class would cause the rider to consider battery consumption, drafting, energy conservation, and actually might have some bicycle style full stand up and pedal finishes. I'm down, who is with me?!!

p.s. I actually see very little difference between Luke's bike and the 200cc stink blaster, accept the stink bike rider might have had a little more self control rather than smoke the rear tire every chance he got. :wink: They both ran the same tires, but the 200cc bike wasn't hitting 70 mph down the straight. I would say ebikes have a long way to go before claiming any bragging rights of clear domination.
 
etard said:
I actually think a 1000w race class would be alot of fun. ...

Quite possibly, but how do you ensure entrants stick to the 1000W ??... are you planning to have a dyno available ?
...or do you rely on the word of the entrant ? ... or what is on the motor sticker ?? :shock:

SoSauty said:
..Super simple 20mph, 30mph, and 40mph class
..Too simple ! .. if your intention is to have competitive races.
straight line speed is only one factor to a lap time or a real comparison.
Cornering, handling, acceleration, rider ability, etc all play a big part.
I hate to keep harping on about it, but many other club race series have tackled this issue before and Bracket racing is the solution most arrive at.
you guys need to check and understand how bracketing works. It really is the simplest way to keep most people happy !
 
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