Why do the top manufacturers embrace 36 volt/ 250 watt power systems?

[mata2maui]

Aloha, I am currently enjoying my ST1 (pictured) but want to up the voltage/wattage for my next ebike to take on Maui's powerful trade winds. Wondering why the big three (Trek, Giant, Specialized) only offer 36 volt , 500-625 Wh batteries and 250w nominal/ 500w peak motors on their ebikes? I have noticed most of the dedicated ebike manufactures that do offer 48 volt systems and 500w+ nominal motors don't have the top drive train components and thru axles found on bikes with 36 volt systems. Is it an issue of engineering power trains that won't stress the bike's other components? The top dedicated ebike manufacturers other than Stromer also embrace 36v/250w systems. I would love to find a bike with 48 volt/625+Ah; 750w nominal mid drive motor; with thru axles and a top of the line drive train.

 

[DaveMatthews]

Love me some Maui!
I bought an 800wh battery for my Giant, so my concern with wind/range has evaporated.

 

[mata2maui]

Love me some Maui!
I bought an 800wh battery for my Giant, so my concern with wind/range has evaporated.

Mahalo Dave, I know that kind of watt hour battery will extend your range but it's still 36-volt, correct? Would the higher Wh translate to more power at the wheels?

 

[fooferdoggie]

the thing is you get real rated power out of the main guys. with the Chinese stuff who knows? plus a lot less weight far longer lasting batteries and reliability and serviceability. plus of for that battery size you get a lot more range. less weight overall too helps. the average bosch power bike is 50 to 55 pounds. hell I have to about kill myself to max out my bike. I have to put out about 550 watts climbing a 22% grade hill to max it out.

 

[DaveMatthews]

Mahalo Dave, I know that kind of watt hour battery will extend your range but it's still 36-volt, correct? Would the higher Wh translate to more power at the wheels?

Cheers mate, and Mahalo!
No, I do not get more power at the wheel at all with the bigger battery. My bike is stock with the 32km/hr limiter and about 70nm of torque.
A high/tough wind in the face would just make me use more battery is all.

 

[Stefan Mikes]

only offer 36 volt , 500-625 Wh batteries and 250w nominal/ 500w peak motors on their ebikes?

Incorrect. Specialized also offers a 48 V/240 W motor on its SL line.

The reasons of the 250 W nominal (and up to, say, 565 W peak power) with maximum 4x Rider's Boost Factor are:

• The European Union being the biggest e-bike market in the world (outside China)
• The Euro regulation requiring a regular e-bike (treated equally with traditional bicycles) be limited to 250 W nominal
• The Euro regulations also read "not more than 48 V"
• A widely accepted industrial rule (in Europe, not in China of course) that the bike assistance shall not exceed the human power more than 4 times (otherwise it is a moped or a motorcycle)
• No throttle, pedalling only
• A less powerful e-bike can be more lightweight
• In case of mid-motors, a 250 W nominal, 85-90 Nm motor is more than enough for either fast ride on the flat or steep climbs.

Interestingly, Stromer is a Swiss brand but it conforms to Euro rules, except they make 45 km/h (28 mph) e-bikes allowed both in Switzerland and the United States.

The reason Specialized has opted for 48 V in the lightweight less powerful SL line is the 48 V battery of capacity of 320 Wh will be as long as the e-bikes bottom frame tube but actually very slim, giving SL e-bikes a stealthy look.

I have noticed most of the dedicated ebike manufactures that do offer 48 volt systems and 500w+ nominal motors don't have the top drive train components and thru axles found on bikes with 36 volt systems. Is it an issue of engineering power trains that won't stress the bike's other components?

No, it is the domain of the mass produced Chinese cr*pware.

I would love to find a bike with 48 volt/625+Ah; 750w nominal mid drive motor; with thru axles and a top of the line drive train.

Certainly you can ask Zen E-Bike in Canada to build such an e-bike for you. With a Chinese motor of course (Zen also builds e-bikes based on Bosch system, which is Euro).

 

[Asher]

No, it is the domain of the mass produced Chinese cr*pware.

It's a shame you know so much and still wildly slander with a broad brush. Cannondale, Trek and Stromer all use 42+ v hub motors.

Adventure Neo Allroad Speed

The S is Adventure Neo Allroad unleashed. It’s a rugged Class 3 electric bike with a powerful electric motor, giving you huge range and boosting your speed up to 28mph.

www.cannondale.com

Also funny that you use mass produced as an epithet, as if premium rivals like Bosch are not mass produced.

Anyhow, I believe the reason is mid drive motors can provide about the same assist with 36v that hub drives can with 48v, so I wouldn't worry about the difference between them purely based on voltage.

 

[Mr. Coffee]

I think the core problem here is that you care more about watts than volts. About the only place volts would really matter is that a higher motor voltage might be a bit zippier, especially from a standing start.

A higher power mid drive (e.g. higher than 250w or so) will likely need a heavier chain, chain rings, and cassette because all of that power is going through the whole drive system.

 

[fooferdoggie]

I think too it's easier to make a less efficient motor with a higher voltage then refine the motor to give you the most power wit the least voltage.

 

[teskow]

Some airplanes use 24 volt systems because they can use a lighter gage wire to carry the same amperage thereby saving copper and weight. I have heard that some autos with miles of copper wiring are considering using a 24 volt system to save copper and weight.
I believe it is the amp hour of a battery, not the voltage that determines how much work it can do.
There must be a reason so many battery operated tools keep going to higher and volts. Maybe someone can enlighten us.

 

[indianajo]

Wondering why the big three (Trek, Giant, Specialized) only offer 36 volt , 500-625 Wh batteries and 250w nominal/ 500w peak motors on their ebikes? I

The limited wh is just a ploy to sell an affordable bike - a vendor doesn't make the sale if their base model costs more than the next brand. Watthours cost, and most customers won't spend more than an hour on a bike. Some models offer an affordable extra battery option, other brands want you to buy an $1100 additional battery and carry it in a bag. $$$$ profits. Especially if there is a repeat sale because somebody stole the extra battery out of the bag while the rider was in the restroom restaurant or store.
Limited wattage is a plan to avoid warranty repairs. Maui has a temptation that would burn any system over 250 w for a rider over 120 lb. Haleakala is not climbable with a 750 w or 1000 w electric motor with a normal male adult unless geared down to 1/2 mph max. At least any motor designed for normal riding. If the 250 w motor stalls out, the rider gives up, turns the power off, and thereby doesn't burn up the motor and return for a warranty replacement. No arguments with the dealer or factory. Customer wanted to climb Haleakela, he should have bought a gas motorcycle.
I find the 48 v geared hub motors I've owned in the past are more capable of climbing the rolling hills around here than the 36 v garbage I can buy now. 3 class laws have pretty much outlawed 1000 w or 1300 w geared hub motors. I can't find any stocked in USA. The hills here are up to 15% for 100' and the loads my bike carries including supplies are up to 330 lb.

 

[JRA]

Amps, not Amp hours. Voltage x Amps = Max Watt output. Because of the "250w" regulations of the EU there is no need to use any higher than a 36v system to achieve this number. In fact while using a 36v most use at least a 10A rating which translates into 360w, technically over the "250w" regulation. But by using some marketing smoke and mirrors and a bit of "oh well" from the regulators and a general amount of confusion about what actually constitutes the "250w" rule the industry rolls on.

Some of the favored brands do use a 48v system such as the Mahle 1.1 but do so in order to use less Amps, which cause heat buildup, in their smaller size that uses less copper windings. The more powerful systems available mostly in the DIY sphere in the past have always used mainly 48v run at at least 15A (720w peak) but also run at up to 30A (1440A) with some attention paid to thermal temps. Totally illegal for use on public roads as they are well over even the US legal 750w regulations.

So throw some 52v into the mix as well as 72v and 96v that are popular with the "hot rod" crowd and pick your poison.

 

[mata2maui]

Incorrect. Specialized also offers a 48 V/240 W motor on its SL line.

The reasons of the 250 W nominal (and up to, say, 565 W peak power) with maximum 4x Rider's Boost Factor are:

• The European Union being the biggest e-bike market in the world (outside China)
• The Euro regulation requiring a regular e-bike (treated equally with traditional bicycles) be limited to 250 W nominal
• The Euro regulations also read "not more than 48 V"
• A widely accepted industrial rule (in Europe, not in China of course) that the bike assistance shall not exceed the human power more than 4 times (otherwise it is a moped or a motorcycle)
• No throttle, pedalling only
• A less powerful e-bike can be more lightweight
• In case of mid-motors, a 250 W nominal, 85-90 Nm motor is more than enough for either fast ride on the flat or steep climbs.

Interestingly, Stromer is a Swiss brand but it conforms to Euro rules, except they make 45 km/h (28 mph) e-bikes allowed both in Switzerland and the United States.

The reason Specialized has opted for 48 V in the lightweight less powerful SL line is the 48 V battery of capacity of 320 Wh will be as long as the e-bikes bottom frame tube but actually very slim, giving SL e-bikes a stealthy look.


No, it is the domain of the mass produced Chinese cr*pware.


Certainly you can ask Zen E-Bike in Canada to build such an e-bike for you. With a Chinese motor of course (Zen also builds e-bikes based on Bosch system, which is Euro).

Mahalo for the info and analysis Stefan.

 

[mata2maui]

The limited wh is just a ploy to sell an affordable bike - a vendor doesn't make the sale if their base model costs more than the next brand. Watthours cost, and most customers won't spend more than an hour on a bike. Some models offer an affordable extra battery option, other brands want you to buy an $1100 additional battery and carry it in a bag. $$$$ profits. Especially if there is a repeat sale because somebody stole the extra battery out of the bag while the rider was in the restroom restaurant or store.
Limited wattage is a plan to avoid warranty repairs. Maui has a temptation that would burn any system over 250 w for a rider over 120 lb. Haleakala is not climbable with a 750 w or 1000 w electric motor with a normal male adult unless geared down to 1/2 mph max. At least any motor designed for normal riding. If the 250 w motor stalls out, the rider gives up, turns the power off, and thereby doesn't burn up the motor and return for a warranty replacement. No arguments with the dealer or factory. Customer wanted to climb Haleakela, he should have bought a gas motorcycle.
I find the 48 v geared hub motors I've owned in the past are more capable of climbing the rolling hills around here than the 36 v garbage I can buy now. 3 class laws have pretty much outlawed 1000 w or 1300 w geared hub motors. I can't find any stocked in USA. The hills here are up to 15% for 100' and the loads my bike carries including supplies are up to 330 lb.

Mahalo, lots of stuff I never thought of.

 

[mata2maui]

Mahalo, lots of stuff I never thought of.

Amps, not Amp hours. Voltage x Amps = Max Watt output. Because of the "250w" regulations of the EU there is no need to use any higher than a 36v system to achieve this number. In fact while using a 36v most use at least a 10A rating which translates into 360w, technically over the "250w" regulation. But by using some marketing smoke and mirrors and a bit of "oh well" from the regulators and a general amount of confusion about what actually constitutes the "250w" rule the industry rolls on.

Some of the favored brands do use a 48v system such as the Mahle 1.1 but do so in order to use less Amps, which cause heat buildup, in their smaller size that uses less copper windings. The more powerful systems available mostly in the DIY sphere in the past have always used mainly 48v run at at least 15A (720w peak) but also run at up to 30A (1440A) with some attention paid to thermal temps. Totally illegal for use on public roads as they are well over even the US legal 750w regulations.

So throw some 52v into the mix as well as 72v and 96v that are popular with the "hot rod" crowd and pick your poison.

Mahalo JRA, apparently its chess not checkers...Thanks for helping.

 

[mschwett]

lots of good reasons already cited, but the most important is that they aren't really limiting their systems to 250 watts.

the vado 5.0 (which i believe is labeled a 250w bike) has a peak output of 560 watts. enough to get you to the 28mph class 3 limit on flat ground, or a nice steady 14mph up the grades most typically seen on american roads. of course there are exceptions but these bikes cover the needs of the vast majority of riders. of course, you'd eat the 710wh battery in an hour or so, but it would be fun!

where do you like to ride in maui? i spent a lot of time around lahaina, launiopoko, kaanapali but never did any riding.

 

[mata2maui]

lots of good reasons already cited, but the most important is that they aren't really limiting their systems to 250 watts.

the vado SL 5.0 (which i believe is labeled a 250w bike) has a peak output of 560 watts. enough to get you to the 28mph class 3 limit on flat ground, or a nice steady 14mph up the grades most typically seen on american roads. of course there are exceptions but these bikes cover the needs of the vast majority of riders. of course, you'd eat the 710wh battery in an hour or so, but it would be fun!

where do you like to ride in maui? i spent a lot of time around lahaina, launiopoko, kaanapali but never did any riding.

Aloha, I like to park at Kanaha Beach Park and take the mostly off-street paved path to Paia and then to Hookipa Beach and back. Another Fav is to park at Lahaina Aquatic Center and ride through Front street and then along the coastal areas and beach parks to Kaanapali, and then up to the parking lot above Black Rock where I turn around. You can enter the Kaanapali hotel area by a small beach park right into the parking lot of the Kaanapali Beach Hotel without having to go onto Honoapiilani HWY. Finally, I like to park at the Kihei Boat ramp and ride out to La Perouse Bay thru Wailea-Makena and back. If the back is sore I turn around at Ahii Kinau marine reserve before you encounter the rough rode to La Peruse. Mahalo.

 

[mata2maui]

I think the core problem here is that you care more about watts than volts. About the only place volts would really matter is that a higher motor voltage might be a bit zippier, especially from a standing start.

A higher power mid drive (e.g. higher than 250w or so) will likely need a heavier chain, chain rings, and cassette because all of that power is going through the whole drive system.

Mahalo for the great info AND helping with my "core problem", LOL.

 

[Stefan Mikes]

Cannondale, Trek and Stromer all use 42+ v hub motors.

Low power hub motors, if you are talking Cannondale or Trek. Next, Stromer (a Swiss company) is very small compared to Cannondale or Trek.
Now, how do you define 42+ V? Fully charged voltage or nominal voltage (like 36, 48 or 52 V)? Because a fully charged 36 V battery has 42+ V actual voltage.

the vado SL 5.0 (which i believe is labeled a 250w bike) has a peak output of 560 watts. enough to get you to the 28mph class 3 limit on flat ground

You meant Vado 5.0 (not the SL). Indeed, the full power Vado 5.0 has the peak power of 565 W (with the nominal 36 V battery).
Vado SL has the same system as Creo, that is, 48 V, 240/240 W nominal and max power. (Which only proofs that a motor of higher voltage does not need to be stronger than a 36 V one).

 

[juggernaut]

I'm of the view more volts = more performance. Whether or not it's needed/desired/legal is another thing.

Comparing like for like - take a 48 volt equipped ebike and throw in a 52 volt battery - come back and tell what your findings are. Plenty of evidence around to suggest a performance boost of in the order of 7.5%.

A further example is the Frey Beast running 60 volts through the Bafang Ultra motor with the appropriate controller and generating torque of 240nm compared to the standard 160nm.