The steepest hills

[Stevil_Knevil]

Ten million -and counting.

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Ride Bikes. Drive Culture. -S

[Toorbough ULL-Zeveigh]

I can see Randy 25 years from now in his rocking chair on his front porch, angrily waving his fist at kids passing by on their ebikes, "Don't you young whippersnaps know you're not hovering efficiently!! I have the world's most efficient ebike ever made locked up in my garage."

[Lowell]

I can see Randy 25 years from now in his rocking chair on his front porch, angrily waving his fist at kids passing by on their ebikes, "Don't you young whippersnaps know you're not hovering efficiently!! I have the world's most efficient ebike ever made locked up in my garage."

Hahahahah....

I rode into Vancouver tonight to drop off some paperwork to a tenant, and as I was climbing the lower section of Knight St. hill (8.0% grade, 82.5ft in 1025ft on the steepest section) at over 45mph I was thinking to myself "This hub motor sucks! I should have built a 5lb motor with gears so I can enjoy the scenery!"

Total climb of 308.4ft, and is the biggest hill I ever have to ride over without going out of my way. 47.8km travelled using 1420Wh, MaxS 86km/h, AvgS 39.7km/h. Damn traffic and red lights... still faster than driving a car in the city though!

[wren]

Wow, I didn't realize what I was stepping into. Anyway, this will be my first e-bike project. It's possible that a hub motor will meet my needs. Hub motors seem to work well for many people in many areas. I would love to hear from anyone who has used a hub motor in my area. I had originally considered a 406/409 and more recently an X5. I first started looking into an e-bike conversion in 2004. At the time, I exchanged some e-mails with Joshua Goldberg regarding the 406/409. Shortly there after, I was in an automobile accident that kept me off the street for two and a half years.

Honestly, I don't mind adding gears. I think it will be a fun project. I'm fortunate enough to have access to the university's shop. So, I'm in a position to machine motor mounts and the like. Also, I suspect that I'll get better performance and efficiency in this city. I could be wrong. I consider the area somewhat exceptional in this regard. Bicycling Magazine once rated Pittsburgh one of the worst cities for biking citing the hills and the lack of bicycle lanes. Also, I'm rolling the dice on this being more economical even outside of battery costs as I may avoid spending money twice: once to try a hub and then again to try gears.

I have no interest in bragging, and I'm certainly not knocking hub motors. Just having some fun, and hopefully transforming my bike into something that can serve as my primary form of transportation. Now, I'm actually quite serious about primary bicycle transportation, fun aside. My spine was damaged in 2004, and I find the seat of my recumbent to be considerably more comfortable than the seat of my car. I've come to loath driving. Spinning helps too as I cramp up if I sit still. Plus, I need to do a minimum of 30 minutes of solid pedaling daily for PT anyway.

Those are some pretty mean hills! What's the typical length?

Well, I'm most familiar with Rialto. The truly nasty section is just over 1/10th of a mile. However, it continues going up hill after that. Also, it's going to be hard to get a running start. In addition to the traffic light, the road jogs coming off the bridge at the base of the hill. The terrain is generally hilly even outside of the nasty sections. Still, some of the nasty sections are a must for me, such as Rialto.

What do you think, would a hub motor work here in a bike intended as a primary vehicle?

By-the-by, I now have a way to make the motor's gears legal in Pennsylvania. So, I haven't scrapped the plan just yet.

Anyway, I think I'll avoid the hub vs geared debate, but I'll happily absorb any input on the matter.

[Lowell]

If you want to climb steep hills slowly, gear reduction is a must, but unless you have multi gears or plenty of voltage, top speed will suffer.

Use the power/speed calculator to figure out how much power you need to go up your favorite grade at your desired speed, and then see how it matches up on the hub motor simulator. A 5304 in a 20" wheel would be a very good hill climber if you want simplicity.

[Ypedal]

Hub motors in small wheels climb well in general.. the X5's do well even at 48v 40 amps, the 4 series pumped up to 72v fair darn well even at 20 amps. 16" wheels anyone ?

[d]

we've got steep hills in san francisco:

(some shots from yesterday)

[d]

more sf:

[Lowell]

A quick check shows Mount Davidson as the highest point in San Fran at 934ft. I'm guessing those hills are only a few hundred feet tops?

[Ypedal]

Holy crap... SF is an insane place for cyclists.. i was already aware of this from your videos.. but daym...

[Lowell]

Brake pads and rotors must sell really well there

[TylerDurden]

Holy crap... SF is an insane place for cyclists..

You should see the messengers.

[d]

Holy crap... SF is an insane place for cyclists..

You should see the messengers.

yup... the most popular bikes right now with the young crowd are fixed gear, single speed, brakeless bikes... i've got one myself and love it.

[TylerDurden]

"Back in the day" we called em track-bikes... but nobody rides em on the track anymore.

[Ypedal]

I can only imagine myself with one of those.. hit the first hill and start to slow down.. Grrr.. struggle.. slow down more.. Brrrtttt ( fart ) .. slow to a stop and fall over on my side..

[d]

here's a video some friends made of riding brakeless fixed-gears around the city...

<embed src="http://www.youtube.com/v/bBTioCLha7g" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"></embed>

[Ypedal]

Nevermind going up hill.. i had not considered the other issue of going DOWN the hills with the pedals attached to the rear wheel.........

Don't that just fry the rear tire?

Sweet lord man... don't get a leg cramp at the wrong time...

[d]

it absolutly fries the rear tires... but the sweet thing is typically thats the -only- thing on the bike that wears out / needs to be replaced or adjusted from time to time.

[EbikeMaui]

When your hub motor or its controler burns up let us know if you would spend $1000. for somthing that will go the distance.

[d]

ebikemaui, why are you so negative all the time? i think most would agree with me when I say it gets old pretty quick.

[knoxie]

Ignore him D

He is just jealous of you as you have a better faster bike, you are 30 years younger you have a beautiful wife and you live in one of the most special places on earth!! jeez I am even jealous of that

Knoxie

[Lowell]

Randy is just bitter that hardly anyone really appreciates or cares about his ebike drivetrain, while hub motors sell by the container load. I for one would have more respect for Randy if he presented his ideas in well written posts, without trying to put down others.

Randy: No matter how skinny the rider, and how efficient the motor, your 1600W has no chance against an X5 hub motor with 6600W. That's great for you that it climbs mountains at 12mph, but don't expect flatlanders to think that's useful.

[EbikeMaui]

Randy is just bitter that hardly anyone really appreciates or cares about his ebike drivetrain, while hub motors sell by the container load. I for one would have more respect for Randy if he presented his ideas in well written posts, without trying to put down others.

Randy: No matter how skinny the rider, and how efficient the motor, your 1600W has no chance against an X5 hub motor with 6600W. That's great for you that it climbs mountains at 12mph, but don't expect flatlanders to think that's useful.

And what 6600 watt controller comes with the X5 ?

[eP]

Randy: No matter how skinny the rider, and how efficient the motor, your 1600W has no chance against an X5 hub motor with 6600W. That's great for you that it climbs mountains at 12mph, but don't expect flatlanders to think that's useful.

You are wrong Lowell.
It is not useful for you, but for most of bikers it is useful. The less power you need the more useful it is as you dont need spend a lot of money for powerful battery pack.

[Lowell]

Randy is just bitter that hardly anyone really appreciates or cares about his ebike drivetrain, while hub motors sell by the container load. I for one would have more respect for Randy if he presented his ideas in well written posts, without trying to put down others.

Randy: No matter how skinny the rider, and how efficient the motor, your 1600W has no chance against an X5 hub motor with 6600W. That's great for you that it climbs mountains at 12mph, but don't expect flatlanders to think that's useful.

And what 6600 watt controller comes with the X5 ?

An off the shelf Crystalyte, modified with IRFB4110 MOSFETs. Total cost less than $200 plus a soldering iron if you don't already own one.