You forgot the 5km to get home at the end.
Don't think so. 5k is 3.1 miles as I recall from my running days:
"for 15.4mi total uphill distance with coasting in between
Have you ridden up this monstrous hill before?
From our indispensable friend, the bicycle speed and power calculator, I see that on road racing bikes these athletes can make it up the 15 miles in about three hours by maintaining 300 watts, or ~6 hours by maintaining 150 watts.
http://www.kreuzotter.de/english/espeed.htm
That's more than a marathon of human energy. Very impressive. Doc might be doing you a favor! This is in Tasman(ia)?
just when you or your batteries are getting knackered.
I read in rcgroups.com that lithium-cobalt overdischarging incidents like I experienced often cause loss of the cell's ability to maintain high power output, while capacity remains relatively unaffected. This general observation fits with my experience. Another member here, Patrick M, uses the same cells I do and reports 1.8C continuous output whereas I'm getting 1C output max, and even that seems to get certain cells (the damaged ones) hot if held too long. If you're interested in constructing your own pack like I did, these are the batteries I used, and the chargers:
http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=1643
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1231
Using coupons and their older, lower prices, I bought these cells for $3/per, and 21 1-cell chargers for $9 each.
If soldering 300 batteries isn't your cup of tea, and you really want to have a shot at success, I'd recommend either four to six of the $749 USD EV Tech lipoly packs others here, like Knoxie, are using:
http://www.texaselectricbikes.com/catalog/lithium-polymer-battery-volt15-hour-p-165.html
arranged in a 2s2 or 3p configuration for 30 or 45 AH at 74 volts.
OR
use the cells I wanted to, but couldn't afforded, the emoli's used in Milwaukee powertools. The owner of bigerc would probably build you a custom pack to spec:
http://bigerc.com/index.php?cPath=21_26
If I remember correctly, the owner's name is Michael Charles and he seems legit and very helpful (we've communicated by email, but I've not bought from him). Or you could buy the individual cells, or take apart Milwuakee V28 batteries:
http://tinyurl.com/373p73
http://www.rcgroups.com/forums/showthread.php?t=508443
The emoli pack would be about 1/3rd heavier than a similar lithium cobalt/lipoly pack but should last upwards of ten years or about 3 times as long as lithium cobalt/lipoly.
OR
Bolting together 30+ AHs of a123's is another DIY possibility:
http://a123racing.com/html/rcdevkits.html
but will also require either their chargers, or 7 regular lithium chargers for every 8s of cells, which would preclude proper balancing without a custom BMS. In order to balance, emoli's can be charged with single cell chargers, one per parallal subpack, like I do my lithium cobalt pack.
However you cut it, you'll need either lithium on the bike, or a strong bicycle trailer with a very strong hitch system to carry enough nickel or lead.
As far as the motor goes, if it's a hubmotor, probably the only reasonable choice due to heat build-up is the crystalyte 5305. A motor running through the gears and chains may be the better option from an efficiency standpoint. Of course motor choice will affect battery specs (wouldn't run 72V through a 36 volt cyclone motor for instance), so choose the motor first.
In case you hadn't guessed its up the side of a mountain.
Figured it wasn't a staircase....
An early configuration of my pack charging (I've since increased battery count to 300 (20s15p) and spaced them over my bike for better weight balance):
, I was riding 1~1 1/2 hours every night and 2~3+ hours each day on weekends, always in hillly terrain and at maximum effort. Currently reduced to 6 nights a week for 40 minutes, the only good side is that I am allowed to sprint as hard as I wish.
