speed beast

[keithhazel]

has anyone been tempted by one of these speed beasts....not a bad looking bike either..

Electric Bike Xipi quantum 800 watt ready to ride on eBay, also, Bikes, Cycling, Sporting Goods (end time 02-Feb-09 13:33:57 GMT)

 

[flecc]

Looks like as direct drive hub, and dual power systems tend to rather inefficient. The range will be very short in the high speed 800 Watt mode, those four heavy SLA batteries could run out in as little as 15 to 20 minutes if flat out on tough terrain using the 1500 Watt peak freely, though you could have covered 10 miles in that time.

Probably a heavy beast though, well over 30 kilos, and those tall forks look distinctly odd.
.

 

[Mussels]

Not much capacity in those 12V LA batteries, it won't go far with that motor.
I imagine the speed that goes will attract attention from plod, though they need to see you, realise what's going on and then catch you. I wouldn't fancy risking my license over it.

 

[Tiberius]

Wonder what the magic turbo boost is. Probably switching the batteries from 2s2p (24V) to 4s (48V), although the same effect could be achieved by a limit in the throttle or the controller.

If it really is 4 x 12V, 12Ah then that's 576 Wh which is a respectable amount. But if that is lead acid and the weight is on the rack the handling is going to be frightening.

Nick

 

[flecc]

Wonder what the magic turbo boost is. Probably switching the batteries from 2s2p (24V) to 4s (48V), although the same effect could be achieved by a limit in the throttle or the controller.

If it really is 4 x 12V, 12Ah then that's 576 Wh which is a respectable amount. But if that is lead acid and the weight is on the rack the handling is going to be frightening.

Nick

It is 4 x 12 Volt SLA, but I wouldn't think they'd use battery switching Nick, since that would leave large charge imbalances. There are switchable direct drive motors on the market and this one may be the dual power type that Team Hybrid used to sell, I think it was a Puma. They acknowledged that it was a very thirsty motor in high power mode and recommended it be used sparingly in that way.

Kraeuterbutter also posted on the dual power subject with a mention of star and triangle configurations to give switchable performances.
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[nigel]

Still it would be fun wizzing by other cyclists i think even the lyrca racers wouldnt catch you not even in your slipstream nigel.

 

[keithhazel]

Still it would be fun wizzing by other cyclists i think even the lyrca racers wouldnt catch you not even in your slipstream nigel.

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i wonder where they will stop trying to go faster then...what if the batteries become lighter and give longer performance,would we still pedal if we could 30mph.........when would it stop becoming a bike and change into a motor bike in our mind...some will say..once its past 15mph its a motor bike as need insurance ect..but then every new bike thats modded is sort of not legal is it.. questions questions and i dont have a single answer....nothing new there then

 

[Tiberius]

Hi flecc,

People do use battery switching and that sort of 2:1 shouldn't cause imbalances. Not saying I approve of it, just that it is possible.

There are motors with switched windings that would do it, but it gets complicated.

Star-Delta switching is an option, but the again the physical switching is not trivial. I'm also a bit worried about this with some controllers as it causes a 60 degree phase shift in the windings.

Nick

 

[flecc]

I agree about star-delta Nick, not a good method.

I couldn't point to that switched level motor which must have had it's own controller arrangements, since Team Hybrid seem to have dropped all the high power stuff from Crystalyte, Puma etc that they used to handle. They're only handling their mobility side and unpowered bikes now.
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[Tiberius]

Star-Delta changing is a brilliant way of making a motor that can operate off either 240 V or 440 V AC. But then its a once only wiring operation at set up.

Nick

 

[kraeuterbutter]

it would be even cooler, when there was some intelligent controller which could do this !

so 6 phases instead of only 3 cables run to the controller
and the controller shifts between triangle and star "on the fly":

starts with star, and when the motor reaches a certain speed, it automatically - in a blink of an eye - switches to triangle for more speed

the software must be so intelligent, that the user nearly nothing notice from that

 

[rog_london]

Geek mode on....

Aha, but it's not truly three phase - remember that these motors are inherently DC motors. So, the controller switches from winding to winding in sequence following the clue from the Hall effect sensors as to what to do next....

With that consideration, you only have 'star' to play with. Imagine how complex the switching would be if you had to operate those coils in 'delta'.

Rog.

 

[winterdog]

to resurrect an old thread this beast looks a bit crazy(not just the price) i noticed it was 30kg! Dam that's heavy

 

[Mussels]

The descriptions look a bit too similar, either he hasn't rewritten it properly or he's using the same motor with inflated figures.
It does look quite tempting though, shame about the big weight.

 

[Straylight]

And no mention of a throttle to help control all that power...

 

[my.motion]

inflated figures.
It does look quite tempting though, shame about the big weight.

with those figure he could easily swap SLA with lifepo4 and still make a profit