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-   -   E bike techknowledgy is prehistoric (https://www.bikeforums.net/electric-bikes/858027-e-bike-techknowledgy-prehistoric.html)

Kevin Harvey 11-16-12 04:21 PM

E bike techknowledgy is prehistoric
 
When one sees the performance of the TESLA car & the fact that that it does not use gears then hub motors can only br called prehistoric.

Allen 11-16-12 04:30 PM

Apples and oranges.

Hub motors don't use gears. Tesla does, one (they used to have two).
Tesla's battery packs also weigh about 100x that of an ebike's.

FMB42 11-17-12 07:17 AM

Prehistoric techknowledgy(?) driven E bikes will be around a lot longer than Tesla Motors. This company, IIRC, can't even sell their current production vehicles in the US at this time (I'm not sure that Tesla is even producing vehicles at moment). This is not to mention that Tesla sales are in the thousands, while E bikes, and E bike kits are sold in the millions.

Allen 11-17-12 08:20 AM

Tesla has no restrictions on selling their vehicles.
They are currently producing three models: the roadster, the Model S, and the Model X. The X is not yet on sale but is expected to be released in 2013 or 2014.

FMB42 11-17-12 09:20 AM

The 2012 Tesla Roadster will be sold in limited numbers only in Europe, Asia and Australia.

Allen 11-17-12 09:25 AM


Originally Posted by FMB42 (Post 14958155)
The 2012 Tesla Roadster will be sold in limited numbers only in Europe, Asia and Australia.

Yes, that is because it based on a Lotus chassis. They have moved to all in house production and are winding down the model. They are bringing out a new sports car after the Model X is on sale.

Kevin Harvey 11-20-12 03:08 AM

Tesla is probably geared as geared hub motor & 1 gear ,but 100times bike range 100x the weight 100x the battery than bike = same but hub motors still not with it or mid drive would not be rated as best. Or tesla would be use gears as mid drive e bikes. A lot less mechanical bits if hubs performed like the Tesla cars.

Scaliboy62 11-20-12 08:07 AM

I believe there's still knowledgeable E-Bike Folk who prefer geared hub motors over non geared for these reasons- Geared motors dont need hall sensors which = simplified controllers, the motor is smaller more compact looks like less of an E-bike & more like a regular bicycle, longer spokes can be installed on smaller hub motor = less breakage & stronger wheel. One of the drawbacks of the geared motors from my understanding is they make a little noise some worse then others. I'm leaning towards a geared hub motor my next build. But as someone mentioned the comparison between a Tesla's & an E-Bike is truly apples to Oranges IMHO.:)

dougmc 11-24-12 02:42 AM


Originally Posted by Kevin Harvey (Post 14967040)
Tesla is probably geared as geared hub motor & 1 gear ,but 100times bike range

Typical E-bike range, 20 miles? (Without pedalling.) Tesla range, 220 miles? Not quite 100 times the range ...

You could add a bunch more battery packs to the electric bike -- it would make it unwieldy to ride, but could get the range into the neighborhood of the Tesla. Not that anybody would want to ride it.

Consider that a E-bike carries something (a person) that weighs 3-5 times as much as the bike, but a Tesla weighs 10-30 times as much as what it carries. It's not really an apples to oranges comparison.

And "prehistoric" does have a well defined meaning. "The wheel" may very well be "prehistoric" -- but Tesla, not so much. At best, you could call E-bikes "old technology", though even that's a moving target as the technologies used vary wildly -- "E-bike" is a mighty wide brush.

unterhausen 11-24-12 11:36 AM

electric motor tech and battery tech is somewhat stalled atm, but the better ebikes are essentially using the state of the art of both

chvid 11-24-12 12:11 PM

I've got nine ebikes...2 trikes, 2 folders, a hybrid, and 4 recumbents (Revives, SunEZ Sport, Rebike) and to call ebikes "prehistoric" is pretty silly, whether geared or ungeared. They are all AWESOME - Lithium is AWESOME. I can go eighty miles fully loaded up with camping gear and a Bob and be totallly comfortable. Calling them prehistoric when we are on the cusp of a major ebike phenom is so wrong. I don't recall any nanophosphate batteries around in the Cretaceous.

rscamp 11-24-12 02:38 PM


Originally Posted by Scaliboy62 (Post 14967412)
...Geared motors dont need hall sensors which = simplified controllers...

It would be more accurate to say geared motors have a bit less need for hall sensors due to higher rpm...

Kevin Harvey 11-26-12 04:25 AM

Ive' had one hub motor ,not geared & made sure when i sold it ,it went to a guy living in a city without hills (500W )I know geared hub would be better than that but I then went to midrive cyclone 500w ,now have 4, sold 4 made up most with liFepo4 (I make up pack so fits snug round bot. front of bikes even with rear suspention), living on a Small mountain in our city if it were not for the gears they'd be useless for me getting home , for myself I use 960w cyclone with nuvinci as I was always having derailer problems with the 36v probably too much thrust on gears , even now nuvinci slips a bit----If a hub motor was as efficient as that Tesla the derailers would not be thrashed the same. Show me a hub motor that can shoot up a staircase as midrives do on their adds.Hall sensors whats that -have seen the wording in parts but wouldnt know what use it would be for. On a cyclone motor the greatest power is in one particular rev range, I beleive geared hub the same ,Electric trains don't have gears with their power all the way up the rev-range.Give me that Tesla motor but a bit smaller.

dougmc 11-29-12 03:47 PM


Originally Posted by ricortes (Post 14998174)
Don't get me wrong, I love E-bikes: They will always be a niche market. Just my opinion, let's say a miracle happened and all the problems were solved. Some kind of fuel cell battery that ran on sugar and only produced drinking water as a byproduct. So cheap to produce they give them away and so small and light they fit in a shirt pocket. Add in new room temperature super conductors and 10 hp electric motors the size and weight of a hair dryer.

You now have an E-bike that goes 200 miles on a 5 lb sack of sugar at freeway speeds. Who is going to use it?

Everybody. Except that it'll be in the form of an electric car rather than an electric bike for most of them.

(Not that sugar is a very good power source -- pound for pound, it costs more than gasoline and only has 1700 kcal of energy vs. 4900 kcal for gasoline. A fuel cell that gets well over the 20% or so that a car engine gets in efficiency from gasoline would be considerably better.)


Add in new room temperature super conductors and 10 hp electric motors the size and weight of a hair dryer.
We don't really need superconductors for that, as that pretty much already exists.

For example, this motor is rated at about 9 hp and is pretty close to the size of a hair dryer as it is. Or if you need a little less, this motor does 4 hp for only $100 and only 2 lbs.

There isn't too much room for improvement in motors left -- room temperature superconductor could certainly help make things smaller and even more efficient, but they're already pretty small and pretty efficient. The biggest issue keeping electric cars from taking off is the battery -- the motors are already ready. Once there's more of them, the electrical grid will become more of an issue, but that can be worked out when the time comes.

As for electric bikes, batteries are the big limitation there too, though there's also the drag caused by the motor when it's not being used (when the person is pedalling instead.) That's no an issue for a car, since the motor is always being used.

rscamp 11-30-12 11:31 AM

Yes, Doug's got it right. In this comparison we don't need any improvement to the electric motor at all. Any further improvements are quite marginal. It is already hands down capable of much greater efficiency with many fewer parts than an IC engine. It also requires much less maintenance, has excellent power, requires many fewer expensive external support components and a much simpler drive system by virtue of its far superior torque characteristic. It also starts easier, runs smoother and is virtually unaffacted by weather and altitude. In short, it is already far superior than an IC engine by just about every metric.

Now the batteries. Oops. Here's where it falls down. :) But as time goes on they just keep getting better. I remember flying electric aircraft on NiCds. Now, with brushless motors and LiPos the performance of electric power often exceeds glow or gas. This trend isn't going to stop.

No argument regarding the relative comfort, speed and utility of the automobile, however. It does come at a price mind you...

fietsbob 11-30-12 04:22 PM

There are alternatives.. Clever Cycle's .. Todd's Stoke Monkey, relocated the typical hub motor outside the wheel
and its driving a left chainring on a crossover crank.. the rest of the gears are available to use.

But it needs the extra space of a Big/Dummy, or Xtracycle added longtail conversion.

Allen 12-02-12 11:42 PM

We are not even close to producing a room temperature super conductor however.
The highest temp a super conductor will work is around -200F.

dougmc 12-03-12 01:25 PM


Originally Posted by ricortes (Post 15009043)
I'm not sure you've thought this out yet. Room temperature super conductors at bare minimum mean instead of running 8 gauge wire everywhere, you can do it with virtually a thread and no transmission losses or overheating. Same thing in the motor/field windings of course.

I thought it through just fine, and even explained.

Motors that can put out 9 hp and are the size of a hair dryer exist today. I gave pretty close examples of consumer level motors, and that's way more power than an electric bicycle needs, and while a car needs a lot more power, it won't mind a motor that's twenty times larger much.

Yes, room temperature superconductors could make these even smaller, more efficient. But they're already good enough now -- the thing keeping electric cars and bikes from taking off is not the motor -- it's the power supply. Batteries. In the future, that could be fuel cells or ultracapacitators, but for now, it's batteries.

Side note: if we could actually invent/discover them, room temperature superconductors could make ultra-inductors a much better power storage device than ultra-capacitators. That might solve the entire energy storage problem right there if they can handle a sufficiently large magnetic field before being made non super-conductive.


Maybe I should have used a fuel cell that ran on ethanol as it would take a smaller leap of faith.
Yes, but the fact that you mentioned sugar was the smallest part of my argument. The more significant part is that motors are good enough already -- it's the power source that's holding electric vehicles back.

Crispus 12-03-12 04:18 PM

Yup. See the thread I just started about my experience with BionX. :(

rscamp 12-04-12 03:58 PM


Originally Posted by ricortes (Post 15015239)
sigh

In fact you missed my point and are still missing the mark for the sake of having a 'how many angels can dance on the head of a pin" type argument. One more time, I was just using a pie in the sky, non existent, will probably never exist, technology example to point out the fallacy of the thread title. I think you are still missing the point in this response.

Room temperature super conductors are currently just as pie in the sky technology as a perpetual motion engine. Had I said "An electric bike powered by a perpetual motion engine" would you get the point? If E-bikes had a free source of unlimited power your grandmother still wouldn't ride one in the rain. How about a cold fusion engine for comic relief.

You are trying to argue with someone that happens to agree with you on the point things are 'good enough.' I would even include properly maintained batteries are good enough. That was integral in my post! It is tangential to topic and I would be happy to participate in the discussion as such, but DON'T invert the point of my post to get in a pissing contest. I love talking about possible future technology but haven't really done it seriously here.

This is a misunderstanding. No one is trying to start a pissing contest. Some posts were not clear on their intent. 'Nuff said.

ChrisRider 12-04-12 06:53 PM


Originally Posted by Kevin Harvey (Post 14956368)
When one sees the performance of the TESLA car & the fact that that it does not use gears then hub motors can only br called prehistoric.

Your right, in the past e bike technology has been really ugly tacky looking chunky batteries, who would want to ride them. Although, coming next year i have seen some huge improvements in the look and performance of e bikes, so im sure they will be better and more popular very soon!

unterhausen 12-04-12 08:21 PM

an ebike that used state of the art tech and was built to the same standards as a Tesla would probably cost $10k or more. Looking in this forum I see that the market for that bike is not here among the enthusiasts. There are various companies that have tried to go with a really high end ebike and it doesn't seem to have caught on at all. Companies are selling what they think they can actually move out the door.

ChrisRider 12-10-12 07:24 PM

You guys should check out the new technology being used by Reef Bikes

Crispus 12-19-12 04:46 PM

I was horribly disappointed with the short life of my BionX lithium battery. I hope THAT isn't what the "cutting edge" is going to be.

Kevin Harvey 12-20-12 07:13 PM

I did look up Reef bikes & not impressed as i know so far no hub motor can not do the hills as mid drive system & if you want one thats already made go to this its virtualy the same as what i make up with cyclone with 500w but my battery front (around bot bar) 12AH home made fibre glass http://www.electricbike.com/lightest-bike/ this would have less AH=---must get picture of me like that I'm older.


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