Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Electric Bikes Here's a place to discuss ebikes, from home grown to high-tech.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 01-28-09, 09:35 AM   #1
ChiapasFixed
hipster traffic dodger
Thread Starter
 
ChiapasFixed's Avatar
 
Join Date: Dec 2007
Bikes: IRO Mark V Pro, home made bamboo track bike, eddy merckx corsa extra, Airnimal Joey commute, UGADA Tikit
Posts: 596
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Nuff Torque on the Bionx?

I am considering putting a bionx system on my Airnimal Joey, since Ive moved to a house at the top of a very steep mountain.
The climb is around 4 or 500 meters in aout 1.5km, so it is pretty steep!! Parts of it are so steep some cars have trouble getting up if they are not careful or savvy...
Roads here in Mexico are not really graded very well, so I am sure this climb is a fair bit steeper than anything one would encounter on a regular "first world" road.
My question is, does the Bionx system have enough toruqe to get me up this hill without excesive peddaling? Even with panniers full of groceries?
Thanks
ChiapasFixed is offline   Reply With Quote
Old 01-28-09, 10:01 AM   #2
unime
adrenaline junkie
 
Join Date: Sep 2008
Bikes:
Posts: 123
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by ChiapasFixed View Post
The climb is around 4 or 500 meters in aout 1.5km, so it is pretty steep!!
I don't believe there is any hub motor capable of handling a 26% (or steeper!) slope. At least not efficiently. To cope with that kind of climb, the motor will need to be geared waaaaay down. I don't even think my Optibike would be up to that climb without switching to a smaller gear. Stokemonkey claims to be able to carry insane loads up that kind of slope, I haven't heard of anything else that would tackle it easily.
unime is offline   Reply With Quote
Old 01-28-09, 05:55 PM   #3
ChiapasFixed
hipster traffic dodger
Thread Starter
 
ChiapasFixed's Avatar
 
Join Date: Dec 2007
Bikes: IRO Mark V Pro, home made bamboo track bike, eddy merckx corsa extra, Airnimal Joey commute, UGADA Tikit
Posts: 596
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
hmm, I had a look at the stokermonkey, but apparently it will only work with an extracycle.
I need assistance on my folder, as I also use it to go on buses, taxis, trains and airplanes!!
ChiapasFixed is offline   Reply With Quote
Old 01-28-09, 07:33 PM   #4
raevyn
Senior Member
 
raevyn's Avatar
 
Join Date: Jul 2008
Location: Alberta, Canada
Bikes: Electra townie 21, electic conversion kit, Dahon folder ,Customized Nashiki
Posts: 115
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
if you need something with more torq, I would suggest looking into a BMC motor kit. its pricier than say a Crystalyte kit, but they are know for having more torq. try emailing info@powerinmotion for more details. Im not the most familiar person in the store for it, but ken would Know, and could maybe even offer you more suggestions. Another thing you could try, which is what my roommate runs with his xtracycle, is getting a crystalyte roadrunner (408) kit, and run a 35amp controller with it. it also beefs up the torq quite a bit. Mind you, he also runs it with a 48v 10.5ah Lithium polymer battery. But considering it get him up some pretty steep hills with about 50-100lbs of stuff being hauled around daily, I would say it is quite an improvement to what he was getting before.
raevyn is offline   Reply With Quote
Old 01-29-09, 01:27 AM   #5
recumelectric
It's easy being green.
 
recumelectric's Avatar
 
Join Date: Jun 2008
Location: in the desert
Bikes: Trek Beach Cruiser, Sun X-2 AX (bent)
Posts: 932
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'd use something with more torque than Bionx.

I've got one that works for me in the flatlands, but I doubt it would do what you need.
recumelectric is offline   Reply With Quote
Old 01-29-09, 07:10 AM   #6
kbdog
On the Humber Trail
 
kbdog's Avatar
 
Join Date: Mar 2005
Location: Toronto
Bikes: Electra Townie, Turf Trike, generic
Posts: 53
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Bike trails often have slopes steeper than one would find on a road. I have never been stopped by one yet with my 350PL. Most hills don't even require moving out of top gear. You will have to pedal though.
kbdog is offline   Reply With Quote
Old 01-29-09, 02:45 PM   #7
unime
adrenaline junkie
 
Join Date: Sep 2008
Bikes:
Posts: 123
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by kbdog View Post
Bike trails often have slopes steeper than one would find on a road. I have never been stopped by one yet with my 350PL. Most hills don't even require moving out of top gear. You will have to pedal though.
I don't think you appreciate the steepness of the road our friend in Chiapas has described. Its slope is the same as an intermediate ski slope and although I have ridden straight down such ski slopes (with the MTB director of the resort in the 1980s), and let me assure you they are freakin' steep! According to this bicycle calculator, a strong rider would manage only 1.7 mph up a slope like that. Probably closer to 1 mph on the steeper sections. Even with 500 watts of combined power the speed would only be around 4mph, far too slow for a hub motor to work effectively.

Maybe another comparison will help. Trail guidelines in the US suggest a 10% maximum grade and 5% overall grade. There are exceptions, to be sure, but we are talking about 30+% slopes here. I don't believe that bike trails often have slopes this steep, certainly not for sustained distances.

Last, consider this: There is a dirt road that goes almost straight up (with one dip across a pass) to some radio towers that I like to ride. It has an average slope of 10% and a maximum slope probably in excess of 20% (just a guess - I haven't measured). With modest effort, I can maintain a 5-6 mph pace up the steep sections on my Optibike with 800 watts of power driving the bike's low gear. Anything slower and the motor really bogs down - enough that riding any slower makes me worry. A comparable hub motor (geared or otherwise) would be running with abyssmal efficiency, providing little assistance and likely overheating.
unime is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 04:25 AM.