0-15mph acceleration of 250W electric bicycle?
- Thread starter carlston49
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That's it. Shame on you!It could have more to do with me saying "Pro Connect"
Go wash your mouth out with soap and water.
But from 0 to 25 km/h I am only in one gear - usually 3rd or 4th it is when the motor cuts out that I change up a gear. That is because I am pedalling and adding about another 120 W to the mix.
I find I can easily keep up with most cars being driven normally away from the lights up till about 25-27 km/ when they start to lose me. Some are even slow enough to make me brake to not run into the back bumper.
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that honour should go to the Woosh Big Bear. The only one in the Woosh range that still has a square wave 20A controller. I calculated that the theoretical time to take the Bear to 15mph on throttle alone should be 5.9 seconds. I can't test it at the moment but will try after the holidays.
I still believe that pedal assist or throttle assist that smoothness equals speed, and crank drives unless linked to a single speed drive train, just don't have the smoothness of gear change that a hub drive set up has.
Any advantage that a crank drive might have or indeed if it even does have any which I don't know, would be lost when changing gear.
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When Atmosphere held the various world championships, the hub-motored bikes with throttles always got away quicker. That's how the Oxygens did so well. In some cases, they pulled out a 10 meter lead before the CDs could get in the right gear. The CD rider (semi-pro) would just about catch up the Oxygen bike towards the top of the hill, but knackered himself in the process, so the Oxygens pulled away again at the finish. And no, the Oxygens weren't "adjusted" for extra speed or power- just normal 15 amps 36v restricted to 15 mph. The Bosch and other CD bikes were probably running higher currents too, but they all got knocked out by hub-motored bikes in the first round.
In the three years it ran, no CD bike ever got in the final, which seems to defeat the idea that CD bikes are better for hills - at least for racing, anyway.
In the three years it ran, no CD bike ever got in the final, which seems to defeat the idea that CD bikes are better for hills - at least for racing, anyway.
How did the Neo cross do?
From my own testing with bafabng bpm 250w abd bafang 250w cst.They are nothing special at 15A.The neo cross has much more low end torque and faster accleration.The neo has a 20 amp controller.But it is stronger than the bpm and cst at 20a also in my experience.The bosch cx is much quiker than the other bosch motors
Dave, a surprising amount of time can be either lost or gained when changing gear, so in respect of speed I'm certainly not going to argue about that one.
1boris, having owned both a Performance Line and CX motor at the same time, I suspect that overall the CX might give a one gear advantage, but if someone sat me on a bike and didn't tell me which system was below me, then told me to pull away, I very much suspect that I wouldn't be able to tell.
In any event, the top speed of the CX versus Performance Line is irrelevant any way, as they both cut off at 15.5mph, and are not designed with speed in mind.
To my mind after having used both systems over identical routes in the Swiss Alps, the CX comes off worse, as it is easily more power hungry in respect of battery consumption. The one gear advantage doesn't even really mean that much either, as the available torque from the Performance line more is more than adequate for any mountain climbing. In respect of climbing, the failure on either system, would be choice of final drive gearing. I have yet to require anything lower that a 15t front and 42t rear on either system.
1boris, having owned both a Performance Line and CX motor at the same time, I suspect that overall the CX might give a one gear advantage, but if someone sat me on a bike and didn't tell me which system was below me, then told me to pull away, I very much suspect that I wouldn't be able to tell.
In any event, the top speed of the CX versus Performance Line is irrelevant any way, as they both cut off at 15.5mph, and are not designed with speed in mind.
To my mind after having used both systems over identical routes in the Swiss Alps, the CX comes off worse, as it is easily more power hungry in respect of battery consumption. The one gear advantage doesn't even really mean that much either, as the available torque from the Performance line more is more than adequate for any mountain climbing. In respect of climbing, the failure on either system, would be choice of final drive gearing. I have yet to require anything lower that a 15t front and 42t rear on either system.
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With a hub-motor everything depends on the motor's winding speed. The lower speed ones obviously make more torque and power at lower speeds (with the same battery and controller). I converted a bike with a 40+ mph Q128 running at 52v and 20 amps. Using just the throttle, it would take about 30 seconds to reach 15 mph, but once it got past 20 mph, it started to fly. I converted another bike with a 15 mph 48v Q128 which would blitz it up to 15 mph. The same motor with different winding speeds might as well be totally different motors.
As someone who was outside the arguments. All the bikes were quick up the hill. The difference was negligible unless you were after nago second differences.
I say again all the legal bikes were good on a very steep hill short climb.
No real difference unless you are into willy waving competition.
I say again all the legal bikes were good on a very steep hill short climb.
No real difference unless you are into willy waving competition.
Dont know your weight but I am 110kg and have tested the performance and cx at many difrent hills(with dongle) and for me the diffrence is significant.Also before the cx came the yamaha system was known to be the most powerful,but now,at least before the new pw-x motor is tested.The cx is the most powerful
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I belive the 250w cst motor had a top speed at about 32kmh,same as neo cross.But The bpm motor had a no load speed 40kmh,
I weigh 75kg, and from my experience using the system off road in extreme climbing conditions, other than in the considerably higher battery consumption of the CX motor, the difference is neither here nor there. It is just one gear.
So why do you think it use more battery if it is not more powerful?
Do you belive Bosch made the CX motor just to waste more battery power without gaining anything
I said that it gives a one gear advantage, so is more powerful. But it is hardly a leap in torque to get excited about.
The best hill climbing combination for duration of ride is a Performance Line and 500wh battery. Any loss in performance can be made up with final drive gearing
From my experience in the Alps, the CX line fitted with a 500wh battery gives roughly the same range of a Performance Line fitted with a 400wh battery.
I guess that we all just have different requirements, judgement and expectations, but I certainly want any less torque than the Performance line for off road use.
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The best hill climbing combination for duration of ride is a Performance Line and 500wh battery. Any loss in performance can be made up with final drive gearing
From my experience in the Alps, the CX line fitted with a 500wh battery gives roughly the same range of a Performance Line fitted with a 400wh battery.
I guess that we all just have different requirements, judgement and expectations, but I certainly want any less torque than the Performance line for off road use.
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OP said "without pedal assistance" so the answer is "a long time" and "not at all". I recently ended up on motor only due to a rear hub problem. Acceleration on the level was very slow indeed and a fairly mild hill got it close to stalling. I stopped torturing the thing and walked up.
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