Smart Ebike

[Paul "Smartbike"]

Hello,
My name is Paul and I have just purchased on of these.Flushed with enthusiasm and of my "cash" my expectations were fully"charged" and I was ready to go.What a huge disappointment I don't think I've seen any change in the battery when attempting to use "regen" both braking and motor. So is there something wrong or do I need to tone down my expectations.

 

[Wicky]

Regen feature is much overrated - You'd need a very long downhill stretch to make any significant gains. i.e coming down from Rockies or the Alps ;-) It features on my KTM P and regen only functions when battery is at less than 95% charge to stop it overcharging - unfortunately there are no stonking great mountain ranges in sunny Essex to make use of the feature.

 

[flecc]

Yes indeed, few e-bikes have regen simply because it's rarely worthwhile. During one review of a Giant e-bike with regen, the highly experienced A to B magazine were unable to detect with certainty if the regen was even working!

Regen becomes worthwhile on much heavier vehicles which travel at much higher speeds, electric or hybrid cars for example.
.

 

[RobF]

If regen worked electricity would be free.

 

[Artstu]

Does it charge the battery as you pedal? (sorry couldn't resist)

 

[halfer]

One of the problems with regenerative braking is that, as you become a better cyclist, you learn to foresee problems ahead, and so you start using the brakes less. Thus, something that isn't very effective to start with ends up not putting much back into the battery at all.

For readers like me who've not seen one of these, here is a link (from 2010 though, maybe there are newer models available).

 

[danielrlee]

Completely pointless on a smart bike. Flecc put it quite well. Regen is not worth doing with levels of kinetic energy achievable on a legal bike. Regen with 4000W from 40mph is a totally different story.

Whatever the scenario, you're unlikely to recapture more than 10% unless starting your journey at the top of a very long hill. Energy recapture is only the half of it though. Regen can reduce brake maintenance to near zero.

A powerful proportional (variable) regenerative braking system is something to behold. I've never felt such brutal yet smooth deceleration on a pedal bike and having now implemented it, I'd never be without at higher power levels.

 

[Alan Quay]

Whatever the scenario, you're unlikely to recapture more than 10% unless starting your journey at the top of a very long hill. .

You can't recover energy at the start of a journey though. Where will you store it?

 

[danielrlee]

You can't recover energy at the start of a journey though. Where will you store it?

Good point.

As an asside, Justin LE made that very mistake during his journey across Canada several years ago. He planned on using regen to ease his descent down a long mountain range at the start of a day's journey, but failed to plan for the energy recaptured and fully charged the battery before he set off in the morning.

 

[supersneak]

On the Smart bike - regeneration cuts in while braking. The only time I ever consciously activate regeneration is on a long downhill through a local park - gravity can easily pull you up to 30 mph plus, or should that be pull you down?
Using the regeneration keeps the speed down to a sensible level and avoids frightening the local wildlife, mostly schoolchildren and dog walkers. This is on a path that legally allows cycling - but better safe than sorry.

Battery use has increased during the recent (very) cold weather, but not enough to worry about using regeneration to top up the battery. Better weather forecast next week, at last!

 

[Paul "Smartbike"]

I am grateful to members of this well versed group on the rights and wrongs good and bad of the Smart Ebike pedelecs and regeneration from brakes and the Bionx motor system. Long extended mountain ranges seem to be the answer here. Thankyou

 

[Paul "Smartbike"]

I have added a file which presents regenerative braking quite hard reading but hopefully useful to this discussion.

 

[RobF]

Look at it another way.

Realistically, how much time will you be regenerating on a ride?

A few minutes at best.

If you plug your battery into the mains charger at home for a few minutes you will get no useful charge.

And the home charger is a lot more powerful.

 

[Paul "Smartbike"]

Look at it another way.

Realistically, how much time will you be regenerating on a ride?

A few minutes at best.

If you plug your battery into the mains charger at home for a few minutes you will get no useful charge.

And the home charger is a lot more powerful.

Good point.....outlined to me as how can you expect a dynamo to recharge a 36v battery? Does this mean the regen just doesn't work or it's pretty insignificant and over hyped. Paul

 

[RobF]

Good point.....outlined to me as how can you expect a dynamo to recharge a 36v battery? Does this mean the regen just doesn't work or it's pretty insignificant and over hyped. Paul

Both, it doesn't work and is over-hyped.

But don't worry about it, you've got a nice ebike to ride which is all that matters.

 

[anotherkiwi]

It is good for braking on long downhill runs. Quite useful if you live in the Alps etc. and you spend your life riding up and down mountain passes. Remember you charge at 42 V and 2 to 4 Amps. Regen provides many more Amps than that on steep down-hills which have to be dissipated as heat.