Diary of a E-Bike Noobie

[Cabledawg1]

Im looking for suggestions. I bought a Trek Shift 3 http://www.trekbikes.com/us/en/bikes/town/recreation/shift_comfort/shift_3/ and want to make it electric. Ive read alot on this forum and have decided a front hub is outta the question because my forks are aluminum.
I weigh 275 lbs and will be using the bike for errands, exercise, and fun. I live near the coast and there are not alot of hills around. It needs to be 48V as that will allow me to use the batteries I allready have. Im heavily into RC planes and my 6S 5000mah packs see between 65A and 130A in my Jets and large scale planes. Ill be able to use my tired packs on the bike and break in my new packs on the bike. Win win for me there.

I dont need to go very fast...maybe 20-25, but want the extra uuumph when needed. I want to be able to pedal as well. Im very mechanically inclined, but really dont want a system I have to fuss with.

 

[dogman dan]

Perfect bike for a rear hubmotor. What's your budget? Since you have a shitload of battery anyway, you might have more to spend on the motor.

I have been really impressed with the E-BikeKit direct drive motor kit. They are located very close to you, a plus if you should need any customer service. A pricy kit, but I like some of the new features a lot, such as the dashboard and water resistant wiring, and the new controller mounts.

I reviewed this kit last year, look in testing and reviews. 36 or 48v, and 5 levels of assist. So when you want to pedal, select level 2-3. With 12s, you might not be able to keep up with the motor pedaling at level 5 using full throttle. 27mph on 48v (14s), so the bike is geared to pedal about 20-23mph. Grab a few 2s packs eventually, you'll enjoy the full 48v.

A much cheaper option is the YES.com kits. The 48v 1000w one is a faster motor, so 12s may get you to 30 mph. Still very perky on 12s. I rode one last week, and was pretty favorably impressed with it. Not as sluggish off the line as some faster wind motors I have ridden.

Lastly, the big buzz this year is the Bafang mid drive kits. I have not been able to ride one yet, but the 750w kit looks really nice. But since you will not be riding up the rocky mountains, or up and down steep Pennsylvania hills, you don't really need the hill climbing ability of a mid drive.

If you are on a budget, I think you'll be very happy with a dirt cheap Yes kit, in the rear hubmotor. Your bike is not right for a front motor.

 

[wesnewell]

Take your pick.
http://www.ebay.com/itm/48V1000W-Electric-Bicycle-LCD-Display-26-Front-Rear-Wheel-Motor-Kit-E-Bike-Hub-/291107275178
http://www.ebay.com/itm/48V1000W-26-Rear-Wheel-Electric-Bicycle-Motor-Kit-E-Bike-Cycling-Hub-Conversion-/231132763662

 

[Cabledawg1]

The kits from yes.com and the Ebay ones look the same. They are pretty inexpensive too. One comes with the LCD monitor and one does not. I would ok with $600, so these options are well within my budget.

 

[Drunkskunk]

With your weight + hills I would stay away from the faster Yes.com kits. they are going to overheat faster up a hill.
The Ebikekits.com motor is great, I've used one for years at 15s of Lipo.
But what I would recommend for you is one of the slower wind "torque" versions and running it at 18s. They climb hills better with less waste heat. Its the same idea as running a lower KV Airplane motor so you can swing a better prop for thrust.
A 2808 to 2810 would be good. I'm not sure who is selling them currently.

 

[wesnewell]

The kits from yes.com and the Ebay ones look the same. They are pretty inexpensive too. One comes with the LCD monitor and one does not. I would ok with $600, so these options are well within my budget.

They look the same because they are the same. xcceries is their ebay seller. There are also other kits from other sellers like mhcorp and dauntlessdeals which are a little cheaper ($259) that are also very good deals, but They appear to be out of stock at the moment. Here's their listings.
http://www.ebay.com/itm/26-Electric-Bike-Bicycle-Motor-Conversion-Kit-eBike-Rear-Wheel-48V-1000W-/370934929537
http://www.ebay.com/itm/New48V-1000W-26-Rear-Wheel-Electric-Bike-Bicycle-Motor-Conversion-Kit-eBike-/281199914680
All of these are about the same afaik and probably come from the same supplier in China, where pretty much all kits come from, no matter if you pay $300 or $600 for one from an ebike dealer.

 

[wesnewell]

And lets dispose of something else. These are not real fast wind motors. They're rated at 470rpm at 48V. There are real fast wind motors rated at 730rpm at 48V. They would certainly not be a good choice for you. But these are. I've had one for over 3 years and 11,000 miles and I weigh 270lbs. With 12s lipo they will do ~28mph wot on level ground. They will have no problems with normal hills like a real fast wind motor will. With another controller and 24s lipo, They will do over 40mph even with my fat ass on them for sorter periods of time and will climb 20% hills at close to 30mph. So unless you have some hills over 20% of a quarter mile, or miles of 10-15% hills these will work more than fine and last a long time.

 

[Drunkskunk]

That Yes.com is a fast motor. True that there are faster, but it is faster than the standard fair of motors out there designed to go ~20mph at 36v .
As for hills, are you still referring to that Stretch of Alpine road? Mapmyride only calls about 20 feet of that a 20% grade, and only if you map it west to east. In reality Its maybe an 8% grade to the top of that hill.
Sure, it's a challenge for 400 feet or so, maybe the steepest road we have around here. But nothing compared to what a real hill is. The OP has real hills, he needs something other than a fast motor.

 

[wesnewell]

Nothing but conjecture. How many of these motors have you ridden or tested? And no, I wasn't referring to Alpine road. nor was I referring to Alpine Drive. I don't know where Alpine Road is. It may only be 8%, but it's irrelevant. Now to quote the op, "there are not alot of hills around". So I don't know where you come up with your conclusion. Probably just pulled out of thin air like so much BS I see here on the forum.

 

[dogman dan]

Well, though he's a big boy, he also lives on the coast and said he's got no hills. The Ebay kit is a fast-er wind, but it will still breeze up hills to 10%. Make a little hotter doing it, but not melt it till the hill is miles and miles long.

Comparatively, it's just about the same wind as a 5304 crystalyte. Not real fast, like a 5303.

Since he's not on a super tight budget, I will say that the slightly slower (standard) wind E-bikekit is worth the extra. At least, till the ebay kit catches up and has the same stuff. Waterproof wiring harness, the lovely slim controller, and a display with similar features that include 36 or 48v operation, and multiple assist levels..

It won't be long, till the ebay kits do have all that. 5 years ago, the E-bike kit was just like todays ebay kits. Jason demanded many small improvements for his kits.

Anyway, the slow windings are almost unobtanium nowdays, except for the E-bikekit's trike model.

Re the above comment. I have ridden both kinds now. I was quite impressed with the Ebay (golden 1000w 48v) kit, despite my long standing preference for much much slower motors.

 

[dogman dan]

Here is a fresh picture of the E-bike kit. I just moved it to my wife's bike. She prefers another bike now, so I motorized it for me to do shorter trips to the dollar store or flea.

It comes with a lot of extra wire length, that you see tucked between the seat tube and the tire. But you gotta admit, that slim controller on the seat tube is downright tidy.

 

[Cabledawg1]

The Ebay one that is listed....is there anything else I should buy....do I need one of those torque arms I've read about?

 

[dogman dan]

Yes, you will need a torque arm or something. But if the bike is steel, you could get away with skipping it.

On rear motors, it's generally different enough from bike to bike that cutting your own from a thick steel plate is often the best thing. Grin cyclery does sell a universal rear torque arm. One is plenty for 1000w.

Sometimes a bike has a large flat dropout plate, which makes using a front TA possible.
One of many TA threads here. http://endless-sphere.com/forums/viewtopic.php?f=3&t=50084

You will then only need stuff to connect your battery to the bike. Put your favorite kind of connector on the controllers battery input wires. Cut off whatever crap it comes with, likely some cheese blades or even horrors, a computer AC plug.

I like to make coroplast boxes to protect my lico packs. Then they can carry in bike luggage bags. EM3ev has a dynamite triangle battery bag. Bikes fall over, and I'll admit to riding hard till I crash. No denting that stuff as you well know. So something hard inside the bag protecting the cells is considered smart.

 

[Cabledawg1]

These are the dropouts on my bike...do I need just 1....or do I put them on both sides?


Im looking at the Grin Tech Rev4 ones from EM3EV

 

[DAND214]

The dropouts appear to be cast aluminum. Yes the ones from EM3ev are good, he also has a slow wind DD hub kit.

Dan

 

[wesnewell]

From what I can see of those dropouts they are really shallow and aluminum. I wouldn't even put a motor in them. If you do, you've got a lot of work to do on them. I'd go buy a cheap bike with steel dropouts before I would screw with those.

 

[Cabledawg1]

From what I can see of those dropouts they are really shallow and aluminum. I wouldn't even put a motor in them. If you do, you've got a lot of work to do on them. I'd go buy a cheap bike with steel dropouts before I would screw with those.

I just bought this bike, so buying another is out of the question. What do you mean by "a lot of work"...do you mean the torque arms...or something else?

 

[dogman dan]

Just ignore Wes when he comments on torque arms. He's in the don't use them camp, making him quite an expert on how hard it might be. Easy to skip it of course, but Wes uses only steel bikes that you might get away with skipping it.

One should be fine, unless you plan to run 72v. Then you want two, or one that is the homemade clamping type. It will be easy to put one on the side without the freewheel.


To me, that looks like a good dropout. The Grin universal rear torque arm should work fine. But a cheaper front torque arm should also work ok. One like this.

Using only the part that attaches to the axle itself, you simply drill a hole in the bike where the hole in the arm lands. If for some reason that won't work you can cut the end off, and drill a new hole in a better spot, just put the nut on before you drill so the bolt can clear the nut. An allen bolt may take up less space if it's tight.

You have the big flat dropout area I like to recommend, So it should be as easy as dill a hole, put the bolt in it. But in addition, you might want to file that dropout 2mm deeper. This will put the center of the 14mm axle on the motor in the same spot as the original 10mm axle. This will help with disk brake alignment.

 

[wesnewell]

Take your rear wheel off and measure the depth of the dropouts. If they aren't at least 14mm, then the motor axle will not fit all the way into them. I've never liked the design of torque arms. That's why I won't buy a bike with aluminum dropouts. A new bike with steel dropouts that will work better than that $600 bike can be had for under $100 new, $50 used.

 

[Cabledawg1]

Ill check the dropouts and take a pic.

 

[dogman dan]

Did I not say file them deeper? 2 mm deeper will center the motor axle in the same spot as the 10mm axle center was. That will do, with the use of a torque arm.

Wes thinks a $150 bike is perfect. I do not. A cheap bike can be adequate at best. But I do agree that steel frames are good, ideally a similar dropout, but steel.

I, and some others here have fitted motors to 15-20 different bikes along the way. We've seen it all, done it all. Others have looked at pictures of it all.

 

[pdooley]

LOL
I appreciate the info and advice from Wes and Dogman, no matter how different it may be.
I'm going through this TA thing right now.

 

[spinningmagnets]

Dogman: the slow windings are almost unobtanium nowdays...except for the E-bikekit's trike model

I am intrigued...a 12T DD hub you say? (googles furiously)
http://www.e-bikekit.com/shop/catalog/Electric_Tricycle_Kits-22-1.html

12-MPH in a 20-inch wheel is 202-RPMs...divided by 36V = Kv of 5.6?

202-RPMs in a 26-inch wheel is 16-MPH (http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=16114) so at double that using 72V (instead of 36V) would be about 32-MPH? (48V would be approx 24-MPH, and 60v roughly 28-MPH?)