Hello from Central Ohio! Seeking advice for the e-bike Im building

[DavidfromOhio]

The kit I just got is an AW 26x1.75 rear wheel 48v 1000whub w dual mode controller. I have a Stowa bike 26 in mountain bike and I'm s try struggling to come up with a solution for positioning the battery. I haven't bought a battery yet but I'd really like to get a water bottle or shark style battery to put in the center of the bike. The problem is theres only about 12 1/12 inches of space along the bar and I didnt realize it before but the batteries I'm interested in that are 48v are 14 inches long. Is there any way I could still mount it? If there was a way I could prop the battery up a couple inches from the bar it seems that I would still manage to be able to fit it. I'm trying to avoid putting a battery on a back rack because the weight distribution would be horrible.

This is a picture of the bike when its folded.

 

[indianajo]

Welcome to the site.
The folding part makes it problematic.
You see in my picture left, I hung the battery off the front in a frame I made out of .5" angle aluminum. Much better weight distribution. My bike has holes in the frame to mount racks on the front without steering them. You'll probably have to hang from the fender boss & handlebars on this bike, swinging the battery with the steering.
You could probably pick up a non-folding MTB frame at a flea market or charity resale shop for $75 or less. In that price range expect overage tire tubes and sticky cables. Don't buy one with rusted brake calipers, shifter pivots, or chain.

 

[PDXzap]

If you can find a metal fabrication shop near by, there are quite a few in Columbus, you could have them make a couple of brackets.
Something like this, shown in red:

If this was a typical "slide in" battery then you might be able to set it up so it could be removed when folded?
Obviously that photo isn't to scale but you can imagine how high you're going to have to go with that battery which isn't ideal.

Have you seen this video? You said you wanted to avoid a back rack mount but using that bike you're going to be limited.

I was in your area a few weeks ago... nice place and nice people.

 

[DavidfromOhio]

Thanks for all the ideas, guys. That rendering above of my bike with the shark battery is exactly what I was talking about, lol! I think for now I'm just going to put the battery in the rear even though I have a rear hub motor and so much weight would be back there. Then I'll figure something else out later.

 

[DavidfromOhio]

Am I missing something? I put the rear hub on which for one thing was an extremely tight fit and I can't get the shimano tourney derailleur on. The original wheel has a round axel. Also, the bolt that comes with this style axel is so big that the derailleur gets in the way. Am I going to have to make this a fixed gear?

 

[indianajo]

I had to grind out the fork slot to fit the axle on a Huffy Savannah. Wear safety glasses.
If your motor+freewheel is too wide, and the bike has a steel frame, you can force the struts apart with a jack made of all thread and a long coupler nut. Of course you'll have to carry it in your flat tire kit, since every time you take the wheel out you'll have to do it again.
Alternative is buy a 6 speed or 5 speed freewheel. Warning, the 5 speed may be made for 1/4" wide chain, shimano went to 3/32" chain with the 6 speed (18 speed mountain bikes).
I didn't have trouble clearing the takeup arm, but I had a SRAM setup when I put in a rear hub motor. You may not have enough boss at the back of the strut to make the takeup clear.
As in, go to the flea market and look at the used bikes. You'll probably find something better for conversion than a foldup frame.

 

[DavidfromOhio]

Because of the shape of the axel (oblong instead of round) I can't orientate the derailleur right to where it screws in. If I bolt the derailleur in the way I'm able to, it brushes up against the motor. Ugh. I thought this would be a fun project but it's just one problem after another and I've already spent so much money.

 

[DavidfromOhio]

I got the derailleur mounted on the axel! Even with installing the torque arm on the rear axel and frame! Now I'm searching for batteries. I noticed golf cart batteries are a lot cheaper ($200) anyone ever use those? Do you need special adapters or do they even work? The ones I see on Amazon dont even say if they're lithium ion.Ot appears they could fit on a back rack though. Ebike batteries are so unbelievably hard to choose from on Amazon because the better the deal, the longer the shipping takes. Ugh.

 

[harryS]

Lead-acid batteries are quite heavy and have a short life when people use the minimum (three or four) to run an ebike. A few years ago, a high school kid was on this forum, powering his ebike with them, and they lasted about six weeks. In a mobility trike or a wheel chair, they aren't called upon to spin a 1000W motor.

On the other hand, they don't go up in flames if abused, or if the internal electronics fail, one reason why it's good to spend the extra money on a quality battery, if you're looking for a lithium ion pack.