Bike Ratings on EBR

[eDean]

On a serious note, you can use the whoo test. If during the test ride portion of the video review Court goes whoo, you know that the bike is sufficiently powered. Did the other bikes you are considering get a whoo? If not, well you have some new insight. I'm not sure if a bike ever got two whoos.

 

[bikerjohn]

John,
-I found an industry rating standard at LEVA. Very little interest is evident from Google searches. I had to search far and wide to find this standard...

I checked out LEVA, it looked like it could be a useful system to rate e-bike. But there doesn't seem to be many bikes represented.

 

[Ann M.]

The LEVA started working on ebike standards about 5 years ago, but it required $$ and manufacturers to agree to follow the standards rating and the dedication of a team to do testing. At the time several bike manufacturers lead by Michael DeVisser of OHM and CurrieTech among the group invested in the process, but the needs to run their own businesses and the lack of funding to take the process further stalled the venture. Do check out Extra Energy, they are a European based version of the LEVA and around since 1992. Here's a link to their tests, some part is done on the road and part testing ergonomics. http://extraenergy.org/main.php?language=en&category=products&subcateg=160. No testing on dynos though!

 

[bikerjohn]

http://extraenergy.org/main.php?language=en&category=products&subcateg=160.

Unfortunately their number of bikes reviewed is very limited too. Seems like Court has the most expansive list of bikes reviewed anywhere!

 

[Ann M.]

@bikerjohn, I put that link to help everyone understand how they do testing at ExtraEnergy. On the main products page, http://extraenergy.org/main.php?language=en&category=products&subcateg=127 they have extensive reviews. Of course, Court's covers more of the hub driven bikes, but Extra Energy uses a test system that is fairly rigorous, but does not include dyno testing.

 

[George S.]

There's a lack of hard data about motor efficiency and drivetrain efficiency. You can measure what come out of the battery with an ammeter. But if you are taking 200 watts out of the battery, how much power is the motor delivering? Obviously it varies. The motor is more efficient, you would figure, cruising along at a decent speed. So maybe it is 80% efficient? But climbing a hill, or starting on a hill? Probably very inefficient.

It's always amazed me that no one can really say what the real difference is between a geared hub motor, a direct drive, and maybe a mid drive, in any set of conditions.

You could take 3 bikes, configured with the GD, DD and MD (same bike model) and run it for 2 hours over the same course, same conditions. You attach an amp hour or watt hour meter that accumulates the total amp or watt hours used. What would the results be?

To test a bike to a set standard you could just simulate conditions on a dyno (flats, hills, whatever) long enough to measure the efficiency of the drivetrain, under different loads. Then do two run down tests of the battery, to see the real capacity. Match the two numbers.

 

[bikerjohn]

There's a lack of hard data about motor efficiency and drivetrain efficiency. You can measure what come out of the battery with an ammeter. But if you are taking 200 watts out of the battery, how much power is the motor delivering? Obviously it varies. The motor is more efficient, you would figure, cruising along at a decent speed. So maybe it is 80% efficient? But climbing a hill, or starting on a hill? Probably very inefficient.

It's always amazed me that no one can really say what the real difference is between a geared hub motor, a direct drive, and maybe a mid drive, in any set of conditions.

You could take 3 bikes, configured with the GD, DD and MD (same bike model) and run it for 2 hours over the same course, same conditions. You attach an amp hour or watt hour meter that accumulates the total amp or watt hours used. What would the results be?

To test a bike to a set standard you could just simulate conditions on a dyno (flats, hills, whatever) long enough to measure the efficiency of the drivetrain, under different loads. Then do two run down tests of the battery, to see the real capacity. Match the two numbers.

Yes test data seems rather lacking especially as it relates to kit build information. Another configuration note for GD and DD would be front or rear hub performance characteristics under differing conditions

 

[EddieJ]

Extending this thread beyond Court and his reviews, one interesting point that this thread does highlight, is the lack of end user reviews by forum members in relation to their own bikes.

Surely, end users adding their own on going reviews can only be a good thing, especially given that Court has a such a limited time frame to format an opinion.

I certainly enjoy reading bike reviews written by owners, and would like to see more.



.

 

[JoePah]

Those reviews are great to gather facts about eBikes, but the ratings and subjective opinions aren't really that helpful.

Before I bought my 2012 STromer Elite in Jan 2014, the model before the ST1, I read Court's review.. He basically panned every aspect of the design, from the pedal assist system, to the component selection. I tested the bike and bought it anyway.. And after 2500 miles couldn't be happier with my purchase.. None of his complaints amounted to anything that detracted from my enjoyment riding the bike.. The range ride and reliability all great. There's a brake squeal that I had to fix, and the kickstand broke.. That's it.

I went back to the same dealer yesterday looking at a road bike and the GM asked me how the Stromer was doing, since I never brought the bike back but once a long time ago. Gave him the story and he told me all the other Stromer Customers, all of whom bought the same model and year, had the same opinion as I.

 

[eDean]

Extending this thread beyond Court and his reviews, one interesting point that this thread does highlight, is the lack of end user reviews by forum members in relation to their own bikes.

Surely, end users adding their own on going reviews can only be a good thing, especially given that Court has a such a limited time frame to format an opinion.

I certainly enjoy reading bike reviews written by owners, and would like to see more.



.

endless-sphere.com has a review section for ebike reviews.

 

[bikerjohn]

Extending this thread beyond Court and his reviews, one interesting point that this thread does highlight, is the lack of end user reviews by forum members in relation to their own bikes.
Surely, end users adding their own ongoing reviews can only be a good thing,...
I certainly enjoy reading bike reviews written by owners, and would like to see more.
.

I have added my hands-on observations with the EG Zurich in the comments after Court's review here: http://electricbikereview.com/eg/zurich-350-ix/
and here: http://electricbikereview.com/community/threads/the-eg-zurich-350-ix.363/

 

[Ann M.]

There's a lack of hard data about motor efficiency and drivetrain efficiency. You can measure what come out of the battery with an ammeter. But if you are taking 200 watts out of the battery, how much power is the motor delivering? Obviously it varies. The motor is more efficient, you would figure, cruising along at a decent speed. So maybe it is 80% efficient? But climbing a hill, or starting on a hill? Probably very inefficient.

It's always amazed me that no one can really say what the real difference is between a geared hub motor, a direct drive, and maybe a mid drive, in any set of conditions.

You could take 3 bikes, configured with the GD, DD and MD (same bike model) and run it for 2 hours over the same course, same conditions. You attach an amp hour or watt hour meter that accumulates the total amp or watt hours used. What would the results be?

To test a bike to a set standard you could just simulate conditions on a dyno (flats, hills, whatever) long enough to measure the efficiency of the drivetrain, under different loads. Then do two run down tests of the battery, to see the real capacity. Match the two numbers.

@George S. that's what the Cycle Analyst helps you do! About $150 bucks, its the industry standard to wire inline with everything else and be able to measure power consumed and if you use the recording feature, then you can download the info and chart your data.

There is an online ebike motor simulator that allows you to vary the parameters of motor, battery, rider+bike weight etc. on ebikes.ca. Fun to play around with and get some feel for motor performance. This website also has a nice, clear description of the geared & direct drive motor types and a bit of math to play around with on Hub Motors page.

 

[George S.]

Hi Ann,

I looked into the CA a couple of months ago. I decided it would be something to do if I bought a kit from EM3EV (or others), where it would be easier to set it up. With a factory bike (X3) under warranty, I'm always cautious.

I've used the Watts Up and Chinese knockoffs ($50/$20), which do the cumulative amp hours. For a solar installation, you just keep seeing the same numbers after a while, so you know what you need to know fairly quickly. There's a wiring diagram for the Watts Up somewhere, for an ebike. You'd mostly get the AH used at the end of a ride. I get an approximation by keeping track of the time to recharge.

I'll look at that calculator for sure. I like the one here:

http://bikecalculator.com/how.html

I think something @EddieJ was saying comething in another thread would really be helpful. Why don't folks post the reviews of their bikes, including real range information for how they ride, where they ride. I might do a one year update on my review.

I'm sure the industry could come up with more honest numbers. There was real misinformation in digital cameras, about how long batteries last. Then they just came up with a standard, which is pretty simple with a camera. Pete does really good run down tests.

Thanks again.

 

[Mike leroy]

John,

I noticed the bikes you mentioned are listed in the category on the main web page. Were your bikes always listed in that category, or did they appear as a result of this thread? I had not noticed that category before.

 

[eDean]

Stumbled across this, just as a case in point. https://www.reddit.com/r/ebikes/comments/2040pk/easy_motion_neo_jet_review/

 

[George S.]

@George S. that's what the Cycle Analyst helps you do! About $150 bucks, its the industry standard to wire inline with everything else and be able to measure power consumed and if you use the recording feature, then you can download the info and chart your data.

There is an online ebike motor simulator that allows you to vary the parameters of motor, battery, rider+bike weight etc. on ebikes.ca. Fun to play around with and get some feel for motor performance. This website also has a nice, clear description of the geared View attachment 2418 & direct drive View attachment 2417 motor types and a bit of math to play around with on Hub Motors page.

Ann,

I looked at that simulator. I have a Prodeco X3, and can't find anything to indicate the brand of motor. The drop down menus make it hard to say what might be close to the motor I have. The curves are interesting because they show where the motors tend to be efficient.

I'd settle for real world amp hours over some kind of course. That is very easy to measure, like with one of these $20 Chinese Watts Up knock-off. I think ebikes are meant to be pedal power plus motor, so the total watts are a mix. This is where I get baffled. If I am moving along at 18 mph, pedaling steadily, but moderately, what is the wattage from the motor, and how do the amp hours add up? Is the motor reasonably efficient when I pedal? More efficient? We don't really need to know this much. I would like to know, for instance, if I went to a mid-drive, doing what I do, similar bike, would the battery last a lot longer, or would I just need a smaller battery, etc. My solution for everything is to buy 1) a bigger battery 2) a second battery.

They all exaggerate range, let's say. But is anyone making claims that their drive train is more efficient? Does anyone say "You'll go 50% farther with our mid-drive"?

The best I can say is that on a typical 20 mile ride, I end up with a recharge time of around 3.5 + hours, and the full recharge time is around 7 hours. I have kill-a-watt meter that shows what is coming out of the circuit, the AC watts, so you can make educated guesses about what is going into the battery. Using the AC out, through the meter, works out to be 90 watts, converted to 44 v, and that is about 2 amps per hour, so it's maybe 8 amp/hours into the battery after a 20 mile ride. The battery is 16 AH.

Still, I would take real life experiences where people explained how they ride. I'll take what Pete does, but he seems to get his bikes for a week or two.

For me, I don't think too much about the limits, because the battery seems to be good for 40 miles, and that is farther than I want to go, at this point. I think we need fairly general information, but fairly precise. Like with cameras, just set the parameters and do the same for every bike. Maybe?

The calculator I referenced shows what happens as you push speed, climb hills, and ride into winds. You basically kill your battery. Those are things people have to consider.

 

[bikerjohn]

John,

I noticed the bikes you mentioned are listed in the category on the main web page. Were your bikes always listed in that category, or did they appear as a result of this thread? I had not noticed that category before.

Court has always had the "Affordable" Category along with the other 5 categories.

 

[Mike leroy]

Ann,

I looked at that simulator. I have a Prodeco X3, and can't find anything to indicate the brand of motor. The drop down menus make it hard to say what might be close to the motor I have. The curves are interesting because they show where the motors tend to be efficient.

I'd settle for real world amp hours over some kind of course. That is very easy to measure, like with one of these $20 Chinese Watts Up knock-off. I think ebikes are meant to be pedal power plus motor, so the total watts are a mix. This is where I get baffled. If I am moving along at 18 mph, pedaling steadily, but moderately, what is the wattage from the motor, and how do the amp hours add up? Is the motor reasonably efficient when I pedal? More efficient? We don't really need to know this much. I would like to know, for instance, if I went to a mid-drive, doing what I do, similar bike, would the battery last a lot longer, or would I just need a smaller battery, etc. My solution for everything is to buy 1) a bigger battery 2) a second battery.

They all exaggerate range, let's say. But is anyone making claims that their drive train is more efficient? Does anyone say "You'll go 50% farther with our mid-drive"?

The best I can say is that on a typical 20 mile ride, I end up with a recharge time of around 3.5 + hours, and the full recharge time is around 7 hours. I have kill-a-watt meter that shows what is coming out of the circuit, the AC watts, so you can make educated guesses about what is going into the battery. Using the AC out, through the meter, works out to be 90 watts, converted to 44 v, and that is about 2 amps per hour, so it's maybe 8 amp/hours into the battery after a 20 mile ride. The battery is 16 AH.

Still, I would take real life experiences where people explained how they ride. I'll take what Pete does, but he seems to get his bikes for a week or two.

For me, I don't think too much about the limits, because the battery seems to be good for 40 miles, and that is farther than I want to go, at this point. I think we need fairly general information, but fairly precise. Like with cameras, just set the parameters and do the same for every bike. Maybe?

The calculator I referenced shows what happens as you push speed, climb hills, and ride into winds. You basically kill your battery. Those are things people have to consider.

George,
I assume you are familiar with the difference between square and sine wave controllers.

I have not seen Yamaha explicitly state their sine wave controller is twice as efficient as conventional (i.e., square wave) controllers. Yamaha is very bad at publicizing technical info. For example, their main web is outdated. The sine wave controller works with motor rotational sensors. Their web page only discusses three sensors. The 2015 Yamaha motor contains four sensors. The fourth type of sensors are connected to the motor.

Anyhow, Yamaha electrical system is twice as efficient. I believe the battery travels twice the distance of a conventional square wave controller. I will dig up the facts. I do not believe the battey is unique. In the SDuro brochure, they listed the battery containing 40 cells for 400Wh. So, 10Wh per cell. I have never seen this before. Is 10Wh per cell typical? Bosch battery weighs 0.3 kg less for 40 cells.

The battery energy density is 139 Wh/kg. I assume this is typical. The range is 100-265.

• We learned that the battery had been tested for range on the ‘Official Extra Energy Testing Route’ in Germany. This route is made up of hills, mixed terrain and stopping and starting. The range figures are then published based on these findings, so they can be fairly accurate and not over exaggerated.
  
  So as you can see the estimated range is 130 Km (80 miles) in ‘Eco’, 85 Km (53 miles) in ‘Standard’ & 70 Km (44 miles) in ‘High’. This range is really good and just shows how efficient the new system is.
  
  This Yamaha battery pack weighs in at just 2.9Kg, so like the motor it is one of the lightest units on the market.The Yamaha battery carries a 2 year warranty and takes approx 3.5 hours to charge from flat. It can be charged both on and off the electric bike.

 

[George S.]

Mike,

This is a typical promo line for a sine wave converter:

Smooth control, more responsive, higher reliability, higher efficiency, higher torque, lower noise

It's another thing where theory has to meet practice. Some form of sine wave controller is showing up in all kinds of motor specs, including low price Chinese kits.

The performance charts for 'any' ebike normally show maybe 70% efficiency in the normal operating window.

I've seen some comps on the Haibike with the Yamaha and the Bosch, and there aren't huge differences. The Yamaha may be a lot cheaper. It's a nice system. With 'high' assist the bike goes 40 miles with a 400 wh battery. The Euro max speed is around 15 mph (for assist), which requires about 150 watts. With light pedaling, the Yamaha works out to be maybe 70-85% efficient. Good, but not that exemplary. It's hard to say what the battery is putting out in any 'assist' mode.

A doubling of efficiency would be tough, just because electric motors are routinely 65-85 % efficient. Internal combustion is miserable, in terms of efficiency:

http://physics.stackexchange.com/qu...ical-efficiency-of-internal-combustion-engine

This stuff is pretty solid, now. No dig against Yamaha, but I doubt it will do much for basic performance. It's the guys who do serious earth moving who are griping about Bosch, but you want to climb hills. This stuff just takes so long to get over here from Europe. It's wild that people were talking about the Bosch mid-drive (for US delivery) before Bafang barely had a mid-drive, and now the BBS02 is just eating up the US market, as the Bosch stuff reaches this market. That's a little nuts, you know? I wouldn't wait for another Euro product to get here, just hoping it has earth-shaking specs.

 

[Mike leroy]

Mike,

This is a typical promo line for a sine wave converter:

Smooth control, more responsive, higher reliability, higher efficiency, higher torque, lower noise

It's another thing where theory has to meet practice. Some form of sine wave controller is showing up in all kinds of motor specs, including low price Chinese kits.

The performance charts for 'any' ebike normally show maybe 70% efficiency in the normal operating window.

I've seen some comps on the Haibike with the Yamaha and the Bosch, and there aren't huge differences. The Yamaha may be a lot cheaper. It's a nice system. With 'high' assist the bike goes 40 miles with a 400 wh battery. The Euro max speed is around 15 mph (for assist), which requires about 150 watts. With light pedaling, the Yamaha works out to be maybe 70-85% efficient. Good, but not that exemplary. It's hard to say what the battery is putting out in any 'assist' mode.

A doubling of efficiency would be tough, just because electric motors are routinely 65-85 % efficient. Internal combustion is miserable, in terms of efficiency:

http://physics.stackexchange.com/qu...ical-efficiency-of-internal-combustion-engine

This stuff is pretty solid, now. No dig against Yamaha, but I doubt it will do much for basic performance. It's the guys who do serious earth moving who are griping about Bosch, but you want to climb hills. This stuff just takes so long to get over here from Europe. It's wild that people were talking about the Bosch mid-drive (for US delivery) before Bafang barely had a mid-drive, and now the BBS02 is just eating up the US market, as the Bosch stuff reaches this market. That's a little nuts, you know? I wouldn't wait for another Euro product to get here, just hoping it has earth-shaking specs.

George,

Fair enough. Why does the Haibike owners manual give an 80 mile range, for a "conservative test". I cannot see any difference in the battery. I can only attribute it to the motor/controller.The Yamaha controller only draws 11 amps. I have been searching in vain to find out how many Amps the Bosch controller draws.

Bosch is about half according to this chart. This exercise is a perfect example why essential perfirmance info needs to be standardized, like car sticker info. It is so frustrating!

The Yamaha gear ratio is 450%, due to the dual chain ring. I need about 450% for 18% grade road.