Is regenerative braking working for you please?

[Jocelyn]

Hi Folks,
I live nr Bristol with an 8 mile each way commute up & down several VERY steep hills. I LOVE my 7 yr old Giant LA Twist Lite which I use with power on for the uphill bits however, my second battery is fading fast sometimes even before I get home. The Giant batteries are dear and, whilst currently investigating re-celling, I can't help feeling that a regenerative system would make more sense for me. However, the Kalkhoff Bionx bikes, whilst well reviewed, seem so costly. And I'm not confident about installing the Bionx kits which also don't seem to be so well reviewed. What are your suggestions please?

 

[Cyclezee]

Hi Jocelyn,

Welcome to the forum.

From my experience with BionX, the only advantage I found from the regenerative braking system was reduced rear brake pad wear, to put it another way, it is an expensive rear brake.

The amount kinetic energy produced by a person on a bike going downhill with what is effectively a rear brake in the case of the BionX is only going to put back a very small amount of energy back into the battery.
F1 racing cars on the other hand, travelling at up to and over 200 MPH generate a huge amount of energy when braking which is then used to give a boost in performance with their KERS system.

The BionX system does work very well, but a replacement battery costs more than a complete eZee kit for example.

A better and cheaper proposition for increasing or extending range would be to buy an eZee powered bike or kit wthe larger Ah battery option or a second battery.

 

[flecc]

There's often an element of perversity in e-bike design needs, and this is one typical area. Regeneration or regenerative braking is easiest to create using a hub motor, but these are less good at climbing the steepest hills due to effectively being in top gear all the time.

Bikes like your Lafree with motors that drive through the gears climb the steepest hills better but cannot easily have regeneration or regenerative braking.

Using a very powerful hub motor can go some way to compensating for hill climbing, but of course their current consumption is much greater, so the amount of possible regenerative energy recovery is proportionately smaller and less useful. Catch 22. Without regen they are an option of course.

My advice is to stick to what type of motor system you like best, which may be your present type. With the latest types from Kalkhoff etc you get much larger batteries so range will not be a problem. You can also solve the problem of brake pad rim wear too, since some of the current crop of e-bikes have disc brakes.
.

 

[oigoi]

I also live in a very hilly area and the rate at which my brakes wear out is a problem. For me, because the amount of energy recaptured by regenerative braking is small, the main benefit would be reduced wear of my brakes. The xipi bikes also have regenerative braking, and cost less than the bionx ones so may be a possibility.

 

[kitchenman]

Hi Folks,
I live nr Bristol with an 8 mile each way commute up & down several VERY steep hills. I LOVE my 7 yr old Giant LA Twist Lite which I use with power on for the uphill bits however, my second battery is fading fast sometimes even before I get home. The Giant batteries are dear and, whilst currently investigating re-celling, I can't help feeling that a regenerative system would make more sense for me. However, the Kalkhoff Bionx bikes, whilst well reviewed, seem so costly. And I'm not confident about installing the Bionx kits which also don't seem to be so well reviewed. What are your suggestions please?

7 years? How many miles have you done? If you love the bike buy the battery ...
Alan

 

[Jocelyn]

Thanks everyone for such great advice - have sent off the battery for re-celling, apparently it's going to come back with 10Ah instead of 6 - will report back

 

[Jocelyn]

I also live in a very hilly area and the rate at which my brakes wear out is a problem. For me, because the amount of energy recaptured by regenerative braking is small, the main benefit would be reduced wear of my brakes. The xipi bikes also have regenerative braking, and cost less than the bionx ones so may be a possibility.

I have some kind of inaccessible hub brake on both wheels - work fine but squeal

 

[flecc]

With these brakes yours is the Giant Lafree Comfort model. The brakes are Shimano's roller brakes, working by rollers travelling up narrowing ramps. These can be greased to remove the squealing noise.

Click on the link below and you'll see one of the brakes illustrated but with the optional cooling disc attached, yours hasn't got that. On that diagram you'll see number 2 which is the grease cap that you remove to apply the special grease. Further down you'll see the grease tube illustrated and it's part numbers for two sizes in the list for you to order it from a cycle dealer:

Shimano roller brake technical document

 

[kitchenman]

Thanks everyone for such great advice - have sent off the battery for re-celling, apparently it's going to come back with 10Ah instead of 6 - will report back

Sorry Jocelyn but I have no info on you! ... Is yours a complete electric bike that you bought or a kit conversion? ... can you give me some details ... perhaps a photo of the bike? ,, or url links ... etc ...
Thanks ...