Inexpensive Hill Climbing Assistance

[sbturtle]

Inexpensive Hill Climbing Solution

Saw your reviews of the Leeds and Hill Topper and felt inspired.

I've also come across in my search "YUNZHILUN iMortor 26 inch" but I'm skeptical of that one.

Trying to go with the least expensive all in one solution.

I wouldn't even mind buying used parts (or a cheap used electric bike to cannibalize parts).

Background: I customized my Kona Fire Mountain with a Raceface 36/22 crankset and SRAM 11/34 gripshift (2x9) gear system. The bike has hydraulic disc brakes, and I added a stem extender, slick tires, and swapped out the front shocks with a Kona Project 2 fork.

I just need something that will help me climb steep hills.

I plan to keep pedaling the rest of the 20/30 miles commute.

Graphs of the inclines:



Any suggestions for the least expensive DIY option?

Thanks!

 

[indianajo]

depends on what bike you have.
If you have a steel frame and 26" wheels, a 1000 W geared hub motor will get up up 15% grade at gross weight 320 lb (my experience) at about 300 W. Plus the geared motors have an internal clutch and don't drag when you are pedaling. They do require torque arms and possibly grinding out the fork slot a thirty second or so. Plus some homemade brackets to mount the controller, display and battery. About $500-600 for a low 7 AHcapacity battery.
Thats for a front wheel motor without the sprocket cluster or disk brake attachment. PAS costs more, switched brake handles cost more, both probably worth it. LCD display costs $60 more, I don't think it is worth it especially if there is a quality problem with the rest of the kit. The voltage readings and milage/speed readings on my LCD display were way off. Buy a separate meter to track your battery state. Aluminum or steel wheel costs more, the plastic wheels the cheap kits come in require a long stem tube to inflate them on the road. Bare motors are cheapest, but when I install a hub in a wheel I have to order three lengths of spokes, the spoke calculator never works accurately.
Most geared hub motors that come up in searches are the bafang fat motor which fits wheels for 3"-5" width tires. Somebody mentioned bafang CST and cute Q100h and Q128h as being thin, but I never see these come up in searches. Another vendor somewhat respected is MAC, also somewhat rare on the actual ebay/amazon market.
Country matters. If you live in China, cost may be less. Switzerland, more. You have to be handy to put a kit on an existing bike. If you're riding a carbon fiber road bike, consider buying a flea market mountain bike with steel frame to experiment on. Wreck your expensive bike later after you know what you're doing. I installed mine without any hand holding from the dealer, just reading his FAQ, but I'm a physicist with Army and factory maintenance experience. Your experience may vary.
We can't recommend vendors with no target country in mind.