Conversion Candidate

Cyborg

New Member
#1
I bought this simple mid eighties Schwinn 5 speed cruiser thinking to add a rear wheel kit (ebay - https://www.ebay.com/itm/26-Electri...on-E-Bike-Motor-1500W-Motor-Hub/322269304808?) but because it has a small bottom bracket, began to consider a mid drive kit.

I know I want a top speed of around 25 mph and 40-50 mile range but the choices are overwhelming for a newbie like me. (Of course, the old girl needs a total R & R rebuild which is not a problem.) Please, what mid drive/ battery combination would be best for this first time project - and many thanks in advance.
 

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JRA

Well-Known Member
#2
For a kit mid drive I prefer the TSDz @ 52v with its torque sensing PAS over the Bafang models that use a cadence PAS. They come stock @ 36v but can be re-controllered to 52v. Also I would suggest the brass gear option and also one with a throttle as it aids getting going from a stop. A 16.5Ah Shark battery looks like it would fit inside the lower triangle and should give you the range you require dependent on speed/terrain/stops/start etc.. The whole kit can be had online for around a grand. Try recycles-ebike.com
 

JRA

Well-Known Member
#4
JRA - recycles-ebike.com is new to me , thank you for that. Is it difficult to 're-controller' a motor to 52v?
They should do the exchange before shipping. Also note that the display will not readout all that well after converting because it was made for 36v initially and still is useful @ 48v. Doesn’t effect the operation or setup of the drive I’m installing a wattmeter on mine and track mileage with an app anyway. I don’t have as much faith in a voltmeter which most are that show a battery/bar type scale.
 
#5
I also am looking to convert an older bike, in my case it is a Roadmaster Chromium Edition. I am looking for a top speed of 20 and am open to suggestions.
 

harryS

Active Member
#6
You can get 20 mph with a 36V motor. You need 48V to approach 25 mph. Riding at higher speeds like that, your battery is fighting to push the wind, and you use it up faster. In my opinion, 20 mph is pretty quick.

Some kits are very flexible on what voltage you can use. Others have circuit or software restrictions. The available mid drive kits tend to be inflexible. You use the voltage as designed. because the controller is inside the motor. Hub motor kits mostly use external black boxes for control. Some will allow different voltages. Some don't. These can be upgraded by the user.

I have a BBS02 mid drive kit on one bike. I can run it on either my 48V or 52V batteries. I would like to re-program to use my 36V batteries, but easier to leave it alone. I've had it up to 28 mph, but the typical speed is 14 mph. I find the cadence sensor to be fine, and the bike is reliable. In my opinion, less effort to install than a hub motor. Yep. Around $1000 to make one. Since I already have batteries, I've thought about building a TSDZ kit for an incremental cost of $350. But they seem fragile, based on user feedback on other forums.

Hub motors. Big ones. Small ones. Front drive. Rear drive. Depends on how fast, how far, and how much money you got. I have a couple of rear hubs on bikes too, 250W and 500W. Most of my riding is recreational, on bike paths with my wife, with pedal assist, so we do fine with the small motors.
 
#8
I bought this simple mid eighties Schwinn 5 speed cruiser thinking to add a rear wheel kit (ebay - https://www.ebay.com/itm/26-Electri...on-E-Bike-Motor-1500W-Motor-Hub/322269304808?) but because it has a small bottom bracket, began to consider a mid drive kit.

I know I want a top speed of around 25 mph and 40-50 mile range but the choices are overwhelming for a newbie like me. (Of course, the old girl needs a total R & R rebuild which is not a problem.) Please, what mid drive/ battery combination would be best for this first time project - and many thanks in advance.
00

1500 watts on that bike ? Do you have a death wish ? Seriously, for one, 1500 watts is not legal on any street. Unless you get it registered as a motor vehicle, and get insurance. I can't imagine any legit insurer, underwriting you insurance for such an old bike, that truly is not designed to handle 1500 watts. on that bike - Try something more like 350 watts, and 36 volts, and be very grateful if you safely can get it to 20 mph without getting in a serious accident. And do a rear hub, not mid drive, as you will be throwing good money after bad, putting a mid drive that is more costly on that old of a bike.
 

harryS

Active Member
#9
Cyborg is going to R&R the bike. With new tires and good brakes, and whatever needed to make it road worthy, why not a mid drive?

They're much better balanced than a cheapo heavy 1000W direct drive and about $200 more. Easy to pedal, even if battery is dead. Easier to change flat tires. I just don't think they were designed to run all day at 25 mph. The gears will melt.

If you want to run all day at 25+ mph, assuming you carried lots of batteries, the direct drive is your guy, at least until someone runs you over.
 
#10
I ordered my BBS01 350 watt kit and received it now to get it on the bike. I did run into a couple of issues, first the bottom bracket is a larger diameter than the crank tube on the motor and second it is 73mm length.
 

Nova Haibike

Well-Known Member
#11
I STRONGLY advise caution when thinking about adding a motor of any kind to an inexpensive bike. Many of these bikes have woefully inadequate brakes, made worse by poorly constructed wheel rims. Even as normal bikes they are often scary to ride. At a minimum, ride the unmodified bike to a high speed and check the braking action. Make sure you would be confident the bike can handle the extra speed and power.
 
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harryS

Active Member
#12
I ordered my BBS01 350 watt kit and received it now to get it on the bike. I did run into a couple of issues, first the bottom bracket is a larger diameter than the crank tube on the motor and second it is 73mm length.
Have you come across this article on BBS02 fitting? There might be an adapter available. Otherwise, you need a different bicycle. Hope you get lucky.
 

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