First Ebike advice

gadadhoon

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Mar 31, 2015
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I'm looking for advice on my first ebike. Here are the basics:

Desired max speed on level ground: 20 mph
Desired max range: 20 miles at full speed, but I'll take less
Bike/wheel size: I'm converting a Specialized Crosstrail elite, which is 700c. The bike has an aluminum frame and front shocks, I'm hoping I can get around that by switching out the shocks for steel forks.
Brake type of motor wheel: no disk
Rider weight: 160 lbs
Terrain: Flat, paved streets.
Budget: $600-$1000

Details: I'll be starting work as a resident physician here in California. I have a fairly free schedule until mid-June when I start. For now, I can muck about if necessary to save money. I want to have a reliable bike by the time I start, because I won't have time to muck about with it then. I'll be using the bike to go back and forth from my house to the hospital and clinics, less than 5 miles each way. I want to have the option of 20 mph without pedaling because sometimes I'm just too tired.

I'm currently looking at the 700c Front PRO 901 conversion kit from GM
http://www.goldenmotor.ca/products/700c-Front-PRO-901-Conversion-Kit.html
And their 36V12AH LiFePO4 Aluminum Cased Battery
http://www.goldenmotor.ca/products/36V12AH-LiFePO4-Aluminum-Cased-Battery.html
My bike if anyone cares (mine has no disk brakes):
http://www.specialized.com/us/en/bikes/multi-use/crosstrail/crosstrail

Questions:
1. Once this system is set up, will it be reasonably reliable?
2. Can I meet my needs better with a different product?
3. Are steel forks and a front hub motor ok, or do I need a bike with an all steel frame?

Thanks for any help!
 
That's setup sounds good. Definitely use steel frame and forks. Also invest in some good tires and tubes. Having a flat on an ebike is not fun. Use a torque arm too.

Post some images when you get a chance.

Good luck !
 
Personaly, the demands on the motor out-lined by your goals are not that great and I would recommend a light-weight geared motor kit to retain the look and feel of a bicycle.
For example, this kit:

http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2011-43-GR8W.234ME
A "201 rpm wind motor in a 700cc wheel @ 48V would be 20 mph.
 
I don't get the "steel frame and forks" advice I see so often here***. Steel can rust and over time that will weaken a frame enough to snap it so why use it if it's not needed?

Aluminium frames these days are strong. The forces placed on a normal aluminium frame down hill bike, for instance, will exceed those on any electric commuter bike. Even the lightest aluminum frame bikes are designed to go down paved hills at speeds in the 30 mph range safely at least, and probably much, much more - which is what a normal bike will do if you point it down a steep hill and let it go.

This guy is about my weight and only wants to do 20mph powered. That's hardly moving on the scale of things, so why add more weight with a heavy steel frame and forks which will just eat more battery unnecessarily? And this is a normal commute, which is hardly going to stress the hardware at all.

***I understand it if you're building a monster bike designed to carry 500kg at 40 - 60 mph.
 
Well, there are alu frames and there are alu frames. Good quality frame, good whether it's steel or alu. Cheap ass bike shaped object from walmart, go for the steel.

To the kit, really, for 20 miles a day, you should get about 1 ah per mile for a 36v battery. You mentioned reliability, and you won't get that pushing a 12 ah battery to it's very end every single day. You'll have to ride super slow to make it on the windy cold days.

So bump your budget up, and get a 36v 20 ah. Nothing I see wrong with your kit choice, nor with any of the huge number of kits with about the same performance. But the budget for a really solid commuter you can charge without worry is more like $1200- $1500. not including the bike. It's just a lot of battery you will need for 20 miles.

But if you can charge at 10 miles, if it's 10 miles to work, then a 10 ah will be all you really need.

If you wanted to go first class, the right kit for your commute from the company I work for would be about $1700. You don't have to pay that much. But you can definitely have a reliable commuter for $1300 or so. For example, a first class kit from whoever for about $700, and a 36v 20 ah lifepo4 battery from pingbattery.
 
The difference between steel and aluminum frames is the resilience of the metals. Steel will cycle many many more times than aluminum before failure. As mentioned above, an aluminum frame will just snap.

Both materials are fantastic if you know their limitations.
 
I am actually about to buy that exact same bike but with disc brakes. I am planning on using BMS battery for mine, but as I have not done it yet and have no experience, so I would take my advice with a grain of salt. This is just from recommendations from other members.

https://bmsbattery.com/ebike-battery/678-36v145ah-bottle-09-panasonic-battery-pack-battery.html

36v 14.5Ah battery with the better quality panasonic batteries, it also comes with a charger (probably cheap and might break), LCD, controller is built into the mounting frame on the battery, and all other ebike peripherals you'd probably need.

https://bmsbattery.com/ebike-kit/632-q100h-36v350w-front-e-bike-motor-wheel-ebike-kit.html

Then a front mounted Q100H hub motor, i've heard good things about this one so I'm going to give it a try. You could also go with the same panasonic battery from them in 48v 11.6Ah to increase speed to 25mph, but you'd take a hit with range. If someone has a different recommendation probably listen to them as I have heard both good and bad things from this vendor. All said and done though if you add in the torque arms this kit comes to around $600 shipped and should go about 15 or more miles per charge at 20mph. Also I'll be starting medical school in 2016 after my deferral year!
 
Also check out these 2 threads with similar bikes, one used a hybrid diamondback and lives in California, the other used the same bike you have.

http://endless-sphere.com/forums/viewtopic.php?f=6&t=66969

http://endless-sphere.com/forums/viewtopic.php?f=6&t=58335

Edit* Looks like the second one got most of it from em3ev, looks like a triangle battery bag kit from there with the mac motor is going to be about $1150 shipped, but its overkill for speed. The range would work if you kept it at 20mph though.

http://em3ev.com/store/index.php?route=product/product&path=45&product_id=185
 
presturtle said:
I am actually about to buy that exact same bike but with disc brakes. I am planning on using BMS battery for mine, but as I have not done it yet and have no experience, so I would take my advice with a grain of salt. This is just from recommendations from other members.

https://bmsbattery.com/ebike-battery/678-36v145ah-bottle-09-panasonic-battery-pack-battery.html

36v 14.5Ah battery with the better quality panasonic batteries, it also comes with a charger (probably cheap and might break), LCD, controller is built into the mounting frame on the battery, and all other ebike peripherals you'd probably need.

https://bmsbattery.com/ebike-kit/632-q100h-36v350w-front-e-bike-motor-wheel-ebike-kit.html

Then a front mounted Q100H hub motor, i've heard good things about this one so I'm going to give it a try. You could also go with the same panasonic battery from them in 48v 11.6Ah to increase speed to 25mph, but you'd take a hit with range. If someone has a different recommendation probably listen to them as I have heard both good and bad things from this vendor. All said and done though if you add in the torque arms this kit comes to around $600 shipped and should go about 15 or more miles per charge at 20mph. Also I'll be starting medical school in 2016 after my deferral year!

Q100H (260 wind), 26" wheel on 36V= 19 to 20 mph.
Q100H (260 wind), 26" wheel on 48V= 21 to 23 mph.
 
motomech said:
presturtle said:
I am actually about to buy that exact same bike but with disc brakes. I am planning on using BMS battery for mine, but as I have not done it yet and have no experience, so I would take my advice with a grain of salt. This is just from recommendations from other members.

https://bmsbattery.com/ebike-battery/678-36v145ah-bottle-09-panasonic-battery-pack-battery.html

36v 14.5Ah battery with the better quality panasonic batteries, it also comes with a charger (probably cheap and might break), LCD, controller is built into the mounting frame on the battery, and all other ebike peripherals you'd probably need.

https://bmsbattery.com/ebike-kit/632-q100h-36v350w-front-e-bike-motor-wheel-ebike-kit.html

Then a front mounted Q100H hub motor, i've heard good things about this one so I'm going to give it a try. You could also go with the same panasonic battery from them in 48v 11.6Ah to increase speed to 25mph, but you'd take a hit with range. If someone has a different recommendation probably listen to them as I have heard both good and bad things from this vendor. All said and done though if you add in the torque arms this kit comes to around $600 shipped and should go about 15 or more miles per charge at 20mph. Also I'll be starting medical school in 2016 after my deferral year!

Q100H (260 wind), 26" wheel on 36V= 19 to 20 mph.
Q100H (260 wind), 26" wheel on 48V= 21 to 23 mph.

So with 700c wheel would it be pushing 25mph? Also would there be no torque for hills with that 260 wind in a 700c wheel? 36V should be good for his 20mph speed and 20 mile range then?
 
So with 700c wheel would it be pushing 25mph?
The Ebike CA motor sim. shows 24.5 mph.
http://www.ebikes.ca/tools/simulator.html
(Use Outrider standard motor)
But only a very fit, lightweight rider with no large hills to climb, should use this combo.
A heavy load would drop the motor below it's efficiency range, causing the controller to pull max. amps. For most, a 201 wind would be a better choice for 700 cc wheel. It would still do 22 to 23 mph w/48V and tackle moderate hills with no rpblems.
I have used 260 Q100H w/ 26" wheel with no overheating and I weight 250 lb.s. But, there are no long hills here.
I also use a larger, durable controller that is not prone to over-heat;
http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2014-3K-SAUG.5TSEX
 
I built the bike with the GM black magic front motor and 36v 12 Ah battery. I took it out for a test run around the block and it was great. This afternoon I tried to ride it to work after lunch. The battery indicator says it's full, but the motor barely even provides assist and won't start unless it's already spinning well. It vibrates excessively. I noticed that the rubber rings on either side of the motor around the axle are sideways and twisted, they were flat before. I'm a little pissed about this, help me out guys, what do I do?
 
lester12483 said:
invest in some good tires and tubes. Having a flat on an ebike is not fun.

I skimmed the thread, missed where you had already started work, and was recommending a mid drive. I'm behind the curve, sorry I will try to get caught up. Best wishes
 
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