I am looking for a workout while commuting. The throttle is less important. This bike has off road mode. Any comments on the reliability of juiced bike? https://shop.juicedbikes.com/collections/e-bikes/products/crosscurrent-s
JRA
Well-Known Member
This is what works for me. 1000w front hub DD motor with a 52v 10.5ah shark pack, 25 amp controller with cruise control and regenerative assist braking. 20 spd drivetrain with a gear range of 28" to 154" gear ratio.
First let me say that over 28 mph efficiency drops way off due to wind resistance, even in still air. Well it starts to have affect around 23 mph actually but gets exponentially worse and you will suck up the wh/mi even on flat ground like the image shows which used almost the whole charge.
Using a drop bar bike helps cut down the wind somewhat but still handles surprisingly well on single track and all the offload situations I have used it for over the past year from sea level to 11k. The two wheel drive feature works especially well in sandy areas, even with the narrowish >40c tires on 700c i23 tubeless rims @ 35psi +/-.
Also using the proper gear ratio and a decent amount of input of your choosing will help forward momentum, and efficiency and give you as much of a workout as you desire.
Flat ground still will eat up wh's if you have to stop and start a lot. Takes a good amount of energy to get back up to speed, even with active pedaling, but it is too much fun to be half way down the block before the cars from the light start going by you. My commute is a <40 mile r/t with about 1000' total elevation change and my average speed is consistently within this range but there is usually a pretty good headwind when I come home which is what this reflects also.
Interestingly it has taken me longer to do this route in my car than by bike. Mix of 2 lane, 4 lane with big shoulder, and neighborhood stop and go for 7 miles once I hit town. Grid lock just kind of fades out of the picture on a bicycle.
Good luck on your quest. The technology is out there.
Trail Cruiser
Well-Known Member
With your kind of application where you ride 34 miles round trip, mostly flat road at speeds faster than 28 mph, that would require enormous energy (30+wh/mile). You will need a 1,000 watt-hour+ battery and you will need a robust hub drive capable of sustained 500+ watts without overheating (a mid drive will just shred your drive train prematurely).
You are right, the ebike that has that potential is the Crosscurrent S with the biggest battery option 1008 watt-hour (42v 21ah)
Or the Stromer with 983 wh battery.
Other ebikes have smaller batteries but they are still capable for the range but you have to slow down a little bit with average speed somewhere in the 22-24 mph to reduce your battery consumption to about 22wh/mile. Or you can bring a charger with you so you can charge up before going back home. These are the other ebike options with smaller batteries.
Magnum cruiser
Ohm
Smartmotion
Bulls outlaw E45
Easy motion Nitro
Magmun Metro plus
Vintage
These are just some of your options. Note that some ebikes will cut the power above 28 mph while others will not.
Source: https://electricbikereview.com/category/speed/
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Thank you! I tried both Magnum peak and Magnum metro. i was able to get to 26m with the Peak and max to 27 miles. Metro was weak. I only can get to 23 miles with the best effort. The sale person says that Magnum has instructions online to program it to Offroad mode to get max to 30 miles. But I wasn't able to find the instruction online. I also tried Stromer S1 sports. I was able to get it to 26 miles max. I felt the Peak was better than Stromer.
Trail Cruiser
Well-Known Member
Thank you! I tried both Magnum peak and Magnum metro. i was able to get to 26m with the Peak and max to 27 miles. Metro was weak. I only can get to 23 miles with the best effort. The sale person says that Magnum has instructions online to program it to Offroad mode to get max to 30 miles. But I wasn't able to find the instruction online. I also tried Stromer S1 sports. I was able to get it to 26 miles max. I felt the Peak was better than Stromer.
Anything above 20 mph, the energy consumption rises exponentially. You consume more than twice the energy at 30 mph vs 20 mph. Maintaining 28+ mph requires a lot of power, overheats the motor, and quickly drains the battery. A good compromise between speed and power consumption is 21-24 mph (average).
Your chain ring needs minimum tooth count of 46 so your cadence is at most 80 rpm when cruising at 28 mph.
Also, it seems the trend is towarding to central drive. Do you think a hub drive is better to maintain a maximum speed for 17 miles one way than center drive?
Above 20 mph, the energy efficiency between hub and mid drive is about the same but the hub drive preserves the life of the drive train (chain ring, sprockets, chain) while the mid drive accelerates the wear and tear and shortens the life of the drive train.
At low speeds, the mid drives with smaller motors tends to be more efficient (longer range per battery charge) and also has better climbing ability with less tendency to overheat due to the leverage from the drive train.
I have both hub drive and mid drive speed ebikes (>28 mph). I don't use the maximum assist level but I still hit 28+ mph on slight down hills. I just set the assist level just enough that I can maintain 22-23 mph on the flat (consuming 20 wh/mile) and then let it rip on the slightest down hills.
Hope that helps.
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very helpful! I also tried eflow E3 Nitro 2013 model. its motor is maxed at 20m. I was able to ride at about 21-24 miles consistently, and was able to max at 26 miles with my best effort. Based on the above info, i am starting to wonder whether class 3 (max at 28m) is 20% to 30% faster than a class 2(max at 20m) for a 17 miles one way commute???
Trail Cruiser
Well-Known Member
When I first had my 500 watt hub drive (2015 Izip Dash) I can barely pedal faster than 25 mph on max assist level. Now I only use level 2 assist most of the time, and switch to level 3 to reach to 28 mph. I rarely used the max assist (level 4).
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Trail Cruiser
Well-Known Member
Assuming everything else is equal (tire pressure, low resistance tires, frictional drag, overall weight, pedal effort, etc...) the major factor for top speed is raw power. Raw power does not necessarily mean the power rating of the motor itself but how much energy can the battery discharge and how much current can the controller (bottle neck) allow to pass through without overheating. So the battery size, quality, health, and state of charge are very important factors. Of course, the faster you go, the more power you consume and the quicker your battery drains down.
Simply saying, the more electrical wattage your battery can spit out, the more of it will also be converted to mechanical wattage by the motor.
Addendum:
JamesY, I just passed by an ebike store today and had a chat with the store owner. The owner mentioned that of all the ebikes, the one that he is most impressed is the Bulls outlaw E45, he said it is gutsier than his Specialized Turbo S and can easily reach 28 mph even on a slight uphill. I think you should try it. It is the only hub drive with a built-in heat sink to prevent overheating of the motor.
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Reid
Well-Known Member
Does anyone know what percentage of electrical energy input actually gets converted into forward motion?
At, say, 500W power consumption, how much energy remains to turn the wheel as opposed to heating the motor?
I presume the conversion efficiency varies a great deal with speed and load?
At, say, 500W power consumption, how much energy remains to turn the wheel as opposed to heating the motor?
I presume the conversion efficiency varies a great deal with speed and load?
Trail Cruiser
Well-Known Member
All electric motors has a bell curve of the efficiency range (albeit skewed) when plotted against RPM. That is the efficiency of converting electrical energy from the battery to mechanical energy in the motor. The peak is usually in the low to mid 80's %. A 500 watt hub drive's peak efficiency will depend on how it is wound and geared. In the US there are the 20 mph and the 28 mph hubs. The peak efficiency will be somewhere below 20 mph (15-18 mph) or for the speed pedelec it will be proportionally at higher speed, maybe from 19-26 mph.
http://www.ebikes.ca/tools/simulator.html
When it comes to the load. The new controllers now use MOSFETS that feed optimum load all the time for maximum efficiency (gone are the inefficient variable resistors of the past), but the optimum current is produced in pulses and the pulses are controlled or modulated by there width, pulse width modulation or PWM. So the load is always near optimum with the new controllers.
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JRA
Well-Known Member
Christopher Castillo
New Member
Stealth makes fast ebikes with an off-road mode. They are very expensive. Most other production model ebikes don't go faster than 20 or 28mph without aftermarket modifications. Sounds like you might want a conversion kit. I think the Bafang BBSHD is the most popular one.
Trail Cruiser
Well-Known Member
To put it into a more tangible perspective,
if a 500 watt-hour battery can have a range of 28 miles, going at 20 mph average speed, then that same
500 watt-hour battery will have a range of only 14 miles, going at 30 mph average speed.
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WilliamT
Active Member
I commute year round by ebike and over time the battery isn't going hold the charge as well. From my experience, I wouldn't go below 13.6 ah for that commute. After two years and a few hundred charges, the range is going to drop a quite a bit and you also want to take into account the drop in range in the winter months.
Geoffrey Bloom
New Member
The bike you are looking for and described is The M-1 Sporttechnik Brand.
I have the SPitzing but the Sterling offers the same power train. I have ben just over 40mph on road.
It will climb straight up a wall if you wanted to.
http://en.m1-sporttechnik.de/das-spitzing-r-pedelec/
I have the SPitzing but the Sterling offers the same power train. I have ben just over 40mph on road.
It will climb straight up a wall if you wanted to.
http://en.m1-sporttechnik.de/das-spitzing-r-pedelec/
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rich c
Well-Known Member
What's the price? $10,000?
