Bicycles for climbing mountains

9 posts / 0 new
Last post
reikiman
reikiman's picture
Offline
Last seen: 10 months 1 week ago
Joined: Sunday, November 19, 2006 - 17:52
Points: 8447
Bicycles for climbing mountains

A couple weeks ago I was chatting with an acquaintance who has been experimenting with electrifying recumbent bicycles and sometimes selling electrified recumbents. He's been using the Heinnemann hub motor for a long time and he told me that 2-3 months ago he got a Crystalyte 5xx series motor to try out.

He lives in Palo Alto and something he's been doing is to push the boundaries of how far his bicycle will take him. One goal he has is to make a trip to Santa Cruz using his bicycle. He's done lots of long distance rides and could ride the number of miles between his home and Santa Cruz, however there is an extensive mountain range in-between. Palo Alto and Santa Cruz are both at sea level, and the mountains in-between have peaks between 1500-2500 feet depending on the route you choose across. On our side of the mountains the land is pretty flat until you get to the base of the mountain, and then it's a pretty straight climb up to the summit. FWIW this mountain range is formed by the infamous San Andreas Fault.

He described some tests he'd done to ride to the top of the mountain. Using dual Heinnemann motors on a recumbent it took an hour to ride to the top of the mountain. The Heinnemann motors overheat pretty easily and shut down, so this hour takes into account stops to let the motor cool down. However with the Crystalyte motor it took him 11 minutes to ride to the top, no need to stop. The route he took is a 1000+ foot climb up Page Mill Rd.

This situation is one of the few instances where regenerative braking starts to make sense. On the ride down the mountain there's a question of how to keep your speed reasonably safe, and rather than keeping the brakes on you could use regen. But I don't know of any bicycle motors that allow for regen...?

LinkOfHyrule
LinkOfHyrule's picture
Offline
Last seen: 13 years 4 months ago
Joined: Wednesday, October 17, 2007 - 14:54
Points: 730
Re: Bicycles for climbing mountains

Every hub motor currently in existence allows for regen.

The controller is really what allows for it. I'm not sure if the C'lyte ones do, but I know the Kelly does (although that's a little big for even an X5).

Fechter, however, devised a clever little separate regen setup using a 3 phase rectifier and a cheap speed controller. It has yet to be tested, but should work.

The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai

wanders
Offline
Last seen: 11 years 9 months ago
Joined: Thursday, October 25, 2007 - 11:03
Points: 21
Re: Bicycles for climbing mountains

Every hub motor currently in existence allows for regen.

Hmm, I believe that some hubs with planetary gear reduction systems (Puma / BMC comes to mind) have freewheels in their transmissions. Freewheel = no regen braking. Then again, some other planetary hubs are not freewheeling, so they can be used for regen. As with all things related to regen braking, YMMV.

All the "direct drive" motors (e.g. all Crystalyte) can be used for regen braking. But the stock Crystalyte controllers don't support it, or at least they didn't. One controller that does support regen braking is the Kelly BLDC controller.

Willie

LinkOfHyrule
LinkOfHyrule's picture
Offline
Last seen: 13 years 4 months ago
Joined: Wednesday, October 17, 2007 - 14:54
Points: 730
Re: Bicycles for climbing mountains
Every hub motor currently in existence allows for regen.

Hmm, I believe that some hubs with planetary gear reduction systems (Puma / BMC comes to mind) have freewheels in their transmissions. Freewheel = no regen braking. Then again, some other planetary hubs are not freewheeling, so they can be used for regen. As with all things related to regen braking, YMMV.

All the "direct drive" motors (e.g. all Crystalyte) can be used for regen braking. But the stock Crystalyte controllers don't support it, or at least they didn't. One controller that does support regen braking is the Kelly BLDC controller.

D'oh! Forgot about those. I was thinking from an electrical standpoint, e.g. the motor could if the mechanicals allowed for it. Yah a geared hub with an internal freewheel won't allow for regen.

Other than the Kelly, I don't really know of any controllers designed for regen. Not enough people would make use of it, save for wear on the brake pads.

The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai

gSPIN
Offline
Last seen: 5 years 3 weeks ago
Joined: Thursday, April 24, 2008 - 04:03
Points: 10
Re: Bicycles for climbing mountains

I tot the Bionix do regen?
Anyway, this ebike does something like 9 modes (current levels?) of regen.

http://www.electricmotionsystems.com/

"Also known as electric braking, the E+ features regenerative braking,
which means that the battery is recharged when the rider brakes."

james joule
Offline
Last seen: 13 years 2 weeks ago
Joined: Monday, June 22, 2009 - 11:16
Points: 20
Re: Bicycles for climbing mountains

Hi, I live in sheffield england and there are a lot of steep hills would regen benefit my e-bike, is it efficient enough to be worth using and is it hard to do, many thanks, james

myocardia
Offline
Last seen: 12 years 7 months ago
Joined: Friday, November 7, 2008 - 04:07
Points: 104
Re: Bicycles for climbing mountains

Hi James, regen isn't very efficient. It's somewhere between 20 & 40% efficient, usually closer to 20%. On something as heavy as a Toyota Prius, or even Vectrix (or any maxi scooter), it's quite beneficial. Since they're quite heavy (compared to a bicycle), it's much harder to stop them, so regen helps a considerable amount. For bicycles, it adds hardly any range at all, usually 2-3%.

Now, if you would regularly be riding down the side of a mountain, it would make total sense to add regen to your bike. For most of us normal folks, it's nice to have if your bike came with it, but it isn't usually worth adding to a current bike. It's easy enough to add, though. You just change out your current controller for one that has regen capabilities. You can buy them for ~$400 USD. AFAIK, the only company making regen capable controllers is Kelly. They're easily available on eBay, if nowhere else.

Robert

decibel1
Offline
Last seen: 11 years 6 months ago
Joined: Wednesday, December 13, 2006 - 09:49
Points: 170
Re: Bicycles for climbing mountains

Please not my recent post about a new regenerative controller from Goldenmotor for electric bikes. My 48V 50A version cost me only $90 including shipping and the controller has lots of other neat features.

Chet
Offline
Last seen: 13 years 4 weeks ago
Joined: Tuesday, July 7, 2009 - 07:31
Points: 3
Re: Bicycles for climbing mountains

Although an old start, this thread has new life. Regeneration is not practical on a bicycle. Using the motor as a generator for braking is a good thing. Using a rectifier from the motor, We need a variable resistance to control plug braking.

Log in or register to post comments

Buy Ecotric bikes, get free accessories!


Who's online

There are currently 0 users online.

Who's new

  • JoeBauers
  • lumpykeyword
  • Mrelectric
  • wanroy
  • copaji4473

Support V is for Voltage