Think about how much that sort of capacity would cost with a Swytch conversion ....................
Help! Looking for an alternative to Swytch and would appreciate some advice in Conversion Kits General Discussion.
- Thread starter SafetyThird
- Start date
It is really that small? Just as my 15AH or even a bit smaller.The whole kit adds 6.5kgs to the bike.
The main advantage is as guerney said, good for hills especially if you need the throttle and long life. Size-wise, the DP case is about the same as a typical HL battery.
That is great, I stand corrected. I think I know where I will buy my next battery.
Another advantage: If his front hub fails to get the bike up very steep hills, he could swap out the controller for a much higher powered one, his larger battery pack will pack a bigger punch, can supply higher amps, also the individual cells in his larger pack will be less stressed discharging current, than if he'd bought a small battery pack. That being said, with a front hub, he might need to add some weight to the front to prevent slipping uphill, which could affect handling of the bike...
You can run it at 48v and around 22A, It would blitz any bike/motor running at 36v and 15A on any road you're likely to encounter. There's also the Xiongda 2-speed, which is like a winch when you run it with 48v.
Front hub-motors are no good for very steep hills because they lose traction.
thousands of bikes with front hub motors are sold in the UK every year. They may lose traction on gravel but even CD bikes and bikes with rear hub lose traction there too. On normal roads, they behave like normal e-bikes. Just let the OP try and ask him later.
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Hub motors are especially good for hill climbing when you have 20" wheels.
From what you've been saying, it's pretty clear that there's a hole in your understanding about how hub-motors and ebikes in general work. A motor is just a transducer. Power is taken from the battery at a rate determined by the controller and sent into the motor. The power is what determines how fast you go up a hill and the torque determines how steep a hill you can go up. If you want to go up a hill faster, you need more power (volts x amps), If you want to go up a steeper hill, you lower the gearing or you increase the current.
Crank motors trade speed for torque. Hub-motors give torque according to how much current you give them. That torque is fairly flat until you get towards max speed, where it drops off with the power.
You can get any amount of torque from hub-motors, and you can get any amount of power. You just have to choose one that matches your requirements. Most of the ones you get in ready-made kits and bikes are a compromise for average riders' average needs, so don't judge all hub-motors by them. Remember, a winch is a hub-motor.
As an example, a Brompton with an AKM 85 motor, which is about the smallest and weakest hub-motor you can get, when running with 14A at 36v, can climb a 14% hill without pedalling at a speed of about 4 mph.
Crank motors can either drive the bike fast or up steep hills, but not both at the same time unless you give it the power for that.
I said very steep hills. If you've ever tried riding one up a 30% hill, you'd know what I'm talking about. You can even see them slipping on 20% hills if the tarmac surface isn't clean, and by that I mean relatively low torque motors with 36v and 15A. Anything more than 15% on gravel or grass is a non-starter.
The rear dropouts of both my bikes are aluminium, so I won't be installing a rear hub motor being driven at high current. I don't want a front hub motor either. Steel framed full sized folding bikes (my bikes must fold) are out, because they're awful quality and I'd have to replace far too many components. I'll just increase the current current linit in my BBS01B mid-drive's firmware, and may buy a sans battery BBS01B kit for the Espresso; use the same battery for both bikes (but not at the same time).
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Helps satanding up, leaning forward to put more weight over the front end of the bike. That always helps.
My Brompton has a front hub motor. I never feel like it loses traction. Rear hubs have better traction but that's not equal to front hubs lose traction.
My (good) experience with the rear hub version of that motor from Woosh (with a 36v 20ah battery)
www.pedelecs.co.uk
Woosh xf08c cassette with rear rack battery
Hi all So I wanted a "tootling about" pedelec to go with my BBS02B boardman conversion and I thought I would try doing this one myself (bit of a novice bike mechanic!). Not going to use it for commuting or in heavy traffic, just day trips on pretty deserted single track roads and maybe cycling...
www.pedelecs.co.uk
Mine does not seem to loose traction either.
I cannot comment on how it would cope on very steep hills, the steepest I have tried it on in my area was a 22%.
You can prevent any front hub motor from spinning when you go up a steep hill by using low power and pedalling hard.
Yes front hub motors can lose traction but that is more about high power hub motors or very thin tyres. A front tyre should always have less pressure than the rear as there is less weight at the front and on fairly wide tyres should be decent. You still have to steer going up hills which requires front traction on any bike. I wonder if this might be one of those cadence sensor issues where basic ebikes give full power as soon as you turn the cranks? A throttle allows fine control of power when ascending. However I have to say on steep hills I would always be peddling to assist the motor. I would never cycle up a steep hill on motor alone.
Generally I think this is a very minor issue or not an issue at all for most front hub motor ebikes. I might think differently with a lightweight road bike, rider and high power hub motor on 700x18 tyres. I do have a Giant Defy I want to convert to an ebike but that will be a rear hub conversion for sure.
Generally I think this is a very minor issue or not an issue at all for most front hub motor ebikes. I might think differently with a lightweight road bike, rider and high power hub motor on 700x18 tyres. I do have a Giant Defy I want to convert to an ebike but that will be a rear hub conversion for sure.
My first ebike, which had a front motor, gave me about 2000 miles of ebikng. It had a normal 1.95 tyre on it and had a 15A controller at 36v, so was an average standard Chinese ebike. We have many steep hills where I live. There were several occasions where the tyre was losing traction on normal roads during steep ascents.
My present bike has had a 1.75 MP tyre on it since I built it 9 years ago (7000 miles). It's going to live longer than me. My friend had a front Bafang BPM motor running at 36v and 22 amps. His front tyres didn't even last 1000 miles.
I can't help noticing the 15A and 22A you have mentioned there in reference to the controllers. A true 250W rated controller is around 7A for the continuous rating of the controller.
I also watched this video today and I've never seen this before but because he was climbing a very steep ascent he put all his weight on the front of the bike hanging his body over the handlebars slightly and by doing so he actually lost traction at the rear. Makes you wonder if by altering your body position you can improve traction on the front. I guess for people that ride like Victorian Dad this won't be an option.
Yes, that's the point. if you go up too steep a hill with the drive through the back wheel, the torque of the back wheel can lift the front one off the ground. I didn't think of it before, but maybe my wheel slipped more than yours because I pedalled harder.
With one of the short steep hills I go up, where my front motor used to slip, I have to be careful that my present bike doesn't completely flip with the torque from the back motor wheel. The front wheel nearly always comes up off the grouind. Maybe I should do it more like the guy in the video, but I'm lazy.
When those guys go downhill, you see them lift their bums off the saddle and stick it right back to try to keep more weight on the back wheel because the opposite happens when you go down compared with going up.
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