Building up a 1984 Schwinn Super Sport - BMS Battery?

[majornelson]

This will be my fourth eBike build but I'm stretching a little on this one and I need the considered wisdom of the forum... Goal is a 15 - 18 mph city style bike using a 1984 Schwinn Super Sport as the donor bike. Acceleration and top end performance are not important- style and usability are the goal.

Back story, cleaning out my in-laws attic we discovered a 1984 Super Sport (mid-level racer) in near perfect condition in their attic. My brother in-law generously donated it to me as he is now in Switzerland (a long way away from Bethesda, MD!).

Although it's a racing style bike, I plan to put traditional upright handlebars on it to make it more of a city style bike. Needs a bit of grease but otherwise in great shape.

Now on to what matters...

Goal- I want to keep it light weight and stealth. I have built the Q100 motor on a couple of other bikes (my other builds use the em3ev MAC motor for more power) and am considering adding a Q100(H) front hub motor to this bike. It's a 12 speed racer (six in the rear) bike and dealing with all of the parts upgrades to modernize or upgrade the drive system to handle a low power rear motor just doesn't make economic sense to me. That is why I think the front wheel motor makes the best economical and performance option.

I am looking at a couple of options (I've previously purchased from greenbikekit.com, bmsbattery.com and em3ev.com with reasonable success):

1) Buy a complete kit from bmsbattery.com including an integrated controller 36v battery and front hub motor:
https://bmsbattery.com/ebike-kit/576-q100-36v350w-front-e-bike-whole-kit-ebike-kit.html#/213-rpm-201/380-display-lcd3
- Lower power ( 36v) but integrated BMS in the bottle battery. (201 rpm most likely or 260 rpm?). I like things that plug and play.

2) Buy the kit sans the battery and add a Luna Cycle battery cube.
http://lunacycle.com/batteries/packs/52v/52v-mighty-mini-cube-ebike-battery-pack-panasonic-ga-7ah-3-pounds/
- which would weigh 3 lbs less and I'd add I'd add to a seat saddle bag or custom leather triangle bag (small). More stealth, power (as the Luna is 52v vs. the 36v for the bottle battery) but less range. Assuming the BMS controller can handle 52v.

3) Buy piece parts for the bike and pick my own controller, rims, etc. but I love plug in play. I'd need more help, advice or luck in picking the right combination to build a custom kit.

Any thoughts on this? I've enjoyed the discussion by a number of members on the Q100 but thought I'd start a separate thread on this one...

Cheers,

Lee

 

[chas58]

or #4) Us the same number of batteries as the Luna Cube, but get 50% more range by staying at 36volts.

That is what I did. I tried to get Luna to make me a 36v cube about 6 months before they came out with this battery. They thought it was a good idea (obviously, not it is on the website), but had no interest in doing a 36v version. 52V was more of their liking. But of course, the 36v has 50% more Ah.

So, I had em3ev build me a cube about 6 months ago. weight of battery and motor is about 9-10 lbs, giving me a 29lb bike (see my build in my sig).

So, it depends on your goal for power/weigh/speed/reliability. 52v isn't going to want to do 15-18mph. For that speed you need a stock Q100 201rpm at 36v.

I choose light weight, low power, high speed, high reliability, stealth, with significant rider input. Your priorities might be different.

Also, I expect you can just put a Q100 with a 7 or 6 speed freewheel on your bike as a rear motor with no problem. The chains and indexing for 6, 7, 8 speed are the same. With a 7 speed freewheel, you just wouldn't use one of the cogs.

Lee, enjoy your build. Looks like fun. I'm jealous!

 

[majornelson]

chas58,

Thanks. I've been all over your build thread for the last three years (wow!) but didn't want to hijack with these questions...

I'll send Paul a note and ask price/availability for the battery he built you. (I already use a Q100 201 rpm with his controller and 52v battery on my Brooklyn Cruiser. I get a little wheel spin at start and I think it goes about 21 mph.)

I assume when you say "52v isn't going to want to do 15-18mph" that it will be faster, correct?

One final thing- I was concerned that the rear dropouts on the Schwinn would have to be stretched too much (though I haven't measured them). Is it correct to assume if I stayed with a six speed freewheel on the Q100 that the it would be closer to 130mm (I think I read that is what the six speed rear was...).

Lee

 

[majornelson]

Also, are you buying from BMS battery or greenbikekit?

 

[majornelson]

And one more thing-

The crazy idea I didn't list was turning it into a single speed. I'll be using it at the beach which is flat... My thought was by the time I bought a new crank, wheel set, etc. I'd be pushing the cost/value envelope, which I've done too many times already.

 

[chas58]

Yep faster. 52v on the 201 sounds like it would go about 21mph at full power.

The Q100 is designed for 120mm single speed hubs. Its in the engineering drawings. You can make it anywhere from120 to 135mm by changing steel spacers that are easy to get to. I just went to the hardware store and bought a nylon "bearing" (basically a hollow cylinder) of the same diameter, and cut it shorter to make it fit 120mm. My road bike is a single speed. Really, with a hub motor, there is not often a need to shift if there are no steep hills.

my battery used 10s3p 30Q cells. about 1.5kg, and just under 10 amp hours (well, it goes as far as my older 10ah battery).

I bought my original motors from green bike kit because they at least made a good effort to enswer my questions, and because they let me by some extras (Like a spare motor) without charging any extra shipping.

 

[Chalo]

That's a nice frame made by Matsushita Electric (Panasonic). I got a pink and white one for my then-wife about a dozen years ago, but I set it up with Rohloff Speedhub, Brooks saddle, cold forged Sugino crank, and other nice goodies.

It's still her favorite bike. Under no circumstances would she ever consider letting me put an electric kit on it.

But as for your project-- the Q100 in front is a great choice for that bike. If 36V gets you the 18mph you're talking about, then why not use 36V? If you choose a 48V or 52V battery, definitely go for the slow RPM motor. If you get a non-bottle battery, I suggest putting it in a handlebar bag. You can mount the controller on the bottom of the bag where it can receive air flow.

 

[majornelson]

All,

Another quick question regarding the Cute Q100. I ended up purchasing a rear 201 rpm (with rim) wheel from greenbikekit...

If I don't need the clearance for my rear freewheel (I may use the existing six speed from the existing wheel), can I safely either replace or cut the spacer on the Q100 on the drive side to reduce the width? I think the current rear wheel is 120mm and (I believe) that the Q100 shipped is 130mm.

Thx!

Lee

 

[LewTwo]

I believe that is a steel frame. You should be able to to safely spread the dropouts to 135mm.
http://schwinncruisers.com/catalogs/1984.html

 

[majornelson]

Thanks. Yes, it is a steel frame and I assumed I could safely spread the rear dropouts.

But I was curious if I could cut the spacer or replace it without causing other issues...

 

[Mündawg]

Why would you use a 52v battery with a 36v controller? That would no doubt fry it yes?

 

[majornelson]

Why would you use a 52v battery with a 36v controller? That would no doubt fry it yes?

In my experience, it won't fry it. I ran that config for quite some time on another bike. You certainly don't get the amps that a larger controller would deliver. My other configuration was a Q100 and the standard greenbikekit standard controller with a 52v 10 ah battery from em3ev.com. I eventually upgraded the controller to a larger one from em3ev.com which provided significantly more power on the bike.

The reason I was considering the 52v from luna was it's small size.

 

[boogieBeats]

Thanks. Yes, it is a steel frame and I assumed I could safely spread the rear dropouts.

But I was curious if I could cut the spacer or replace it without causing other issues...

You'll most likely be fine spreading the frame to 130. I get the impression you haven't set a frame before. Since your bike is not made of "meat metal" like most schwins these days, I advise being very mindful. Think of a paper clip bent to many times.

From experience spreading a few Reynolds and Columbus frames (and ruining one), you have about 2 chances on each chain stay to get the cold set right. After that the frames will start feeling soft and possibly get out of alignment when you put any power into them. I currently have a Schwin Super le Tour and Team Fuji set a 132mm. Modern wheels and a cassette free hub make a world of a difference!

So far this is the best write up I've seen on setting a frame.
http://www.sheldonbrown.com/frame-spacing.html

I'll be keeping a eye on your build as I just ordered a q100cst from BMS for my first build. Good luck!

 

[majornelson]

boggieBeats,

Thanks. Q100 has a large spacer on the freewheel side and I'm planning on using the existing six speed freewheel on the bike. My thought was to either spread the rear forks or reduce the spacer (assuming the six speed freewheel is smaller). But I don't know if that will impact the hub motor in any way. Maybe the rear wheel with the Q100 will need to be re-dished?

Thanks.

 

[boogieBeats]

majornelson,

Maybe the rear wheel with the Q100 will need to be re-dished?

In regards to wheel dish. If you reduce the spacer, the wheel will need to become more centered on the hub for a proper dish. This won't be a bad thing as it will even out and reduce stress on the spoke flanges.

That said, I'd still recommend spreading the frame. The benefits are that you can continue to use modern and interchangeable parts for the rest of the bike's life. Since you have semi horizontal dropouts, if you don't get the alignment perfect, you have a little wiggle room to align the rear wheel.

Are you taking any measures to prevent the wheel from slipping in the dropouts beyond torque arms?

 

[spinningmagnets]

If you choose a 48V or 52V battery, definitely go for the slow RPM motor

I agree. I have a car that can easily do 120-MPH, but I drive it at the speed limit. It is nice to have a small amount of power in reserve when a problem arises. Geared hubs are at risk for heat issues when you apply extra amps. I recommend using the Q100H with two torque-arms, and buying a 52V battery from Luna (50V is the same 14S if buying from em3ev).

My recommendation is based on your stated flat terrain, so...a more expensive mid drive is not required. You "may" find that when you have extra power available, that you don't need as many gears. Many builders have been able to eliminate the front derailleur as a result. The rear wheel can have a 7-speed freewheel, or a 9-speed freehub, but...a light bicycle with a light rear hub has been considered by experienced builders as a viable option (see: ES member Kepler).

 

[majornelson]

Thanks for all of the input. Here's what I did:

1) Spread the rear forks to 130mm (using Sheldon's method) and confirmed with string that they are spread evenly.
2) Removed the second chainring. No real requirement for it and it looks cleaner.
3) I had already ordered the Luna battery and charger. Love the size and weight... perfect for my needs. I'm searching for a small leather or canvas bag to hold the battery (and maybe the controller, though I had a frame mount case for it) in the bike's triangle. I ordered a leather case on eBay but it ships from China and won't be here for a couple of weeks. I may try to have a custom one made, depending on costs. I want it to fit in the triangle and attach to the top tube and seat tube. The challenge is that most frame bags aren't wide enough for the Luna battery... really made just for tools. And I don't want a monster bag.
4) Ordered the Q100 at 201 rpms and a stock greenbikekit small controller. If I ever want to goose the performance, I can upgrade to a slightly larger one (but with the risk of stressing the motor). I've done this on another city bike I have, so far, so good.
5) In spite of all this, the rear wheel has to be dished. I took the bike to my LBS today and I'll get it back on Tuesday. The tire was offset from center by about 8mm. Again, the rear forks were spread evenly so it's just the classic issue of modding an old bike...

So... the project is coming together, piece by piece. I'll post before and after pictures in this thread once it's completed.

Thanks for all the help!

Lee

 

[motomech]

I'm running a Q100C (201)on 12S LiPoly (46V) and a Elifebike 17 Amp controller and no stress, quite smooth actually;

The "C" version has less copper than the "H", or even the standard and the latter two will take even more and remain smooth.
The most I have ever put thru a Q100(and it was a "H")was 25 Amps and it was too much. They start to "growl" @ around 22 Amps(@ 48 V).
Look forward to seeing pic.s.

 

[majornelson]

Thanks! Looks great... I'll post pictures once I'm done. Hopefully, it can look as natural/stealth as yours...

Lee

 

[chas58]

Thanks for all of the input. Here's what I did:
5) In spite of all this, the rear wheel has to be dished. I took the bike to my LBS today and I'll get it back on Tuesday. The tire was offset from center by about 8mm. Again, the rear forks were spread evenly so it's just the classic issue of modding an old bike...
Lee

Lee - so the wheel was not dished when you got it, and had to be dished by the LBS to offset it 8mm?

 

[majornelson]

Yes, the wheel is being dished by my LBS (I think it was off by 8mm or so- I measured/estimated with a caliper the center of the tire vs. the center of the bolt for the rear brake). I don't know if the frame somehow contributed to the issue or it was simply that the wheel was not dished properly at the factory.

 

[chas58]

I don't think they are often done properly by the generic chinese build. I have one that I really have to over tighten the spokes on the cassette side to get it to shift over there. It would probably be happier with shorter spokes on that side. Fortunately my second motor i bought bare, and put the significant shipping costs of a high volume wheel towards getting a locally built wheel. Much less headache in the long run. The biggest shock with my chinese wheel is that it started unraveling after several trips, leaving me stranded on the side of the road. I sure wasn't expecting that!

 

[majornelson]

Bike is coming along... I should have photos by next weekend.

Quick question- Does anyone have a link to the programming manual for the CON63 controller and LCD display? I was able to enter setup mode but it's not clear what all of the options do...

Thanks!

Lee

 

[Chalo]

I don't think they are often done properly by the generic chinese build. I have one that I really have to over tighten the spokes on the cassette side to get it to shift over there. It would probably be happier with shorter spokes on that side.

The length of the spokes doesn't matter; only the tension. It helps to lace the spokes all on the right side of the hub flanges.

 

[majornelson]

For the manual, I found a link on bmsbattery.com for both the lcd-5 and lcd-3 display.

It looks like the lcd-5 (which I have) does not have the "c" parameters, only the "p" parameters. The link is here: https://bmsbattery.com/index.php?controller=attachment&id_attachment=5

I am using a 52v battery and a Q100 along with the CON63 sine wave controller from greenbikekit.com.

I entered the following parameters... can anyone comment if they are correct?

P1 = 87 (P1 = motor gear reduction ratio× number of rotor magnet pieces). I have no idea what this is but this was the default.
P2 = 1 (P2 = P2 is wheel speed pulse signal setting mode per revolution). Looks like this controls the speedometer. I'm guessing since I only have one magnet on the spokes, it should be one.
P3 = 1 (power assist control mode). A "1" setting is "imitation torque control" mode vs. speed control (setting of 0). Assume this is what I want.
P4 = 0 (handlebar startup mode). A setting of "0" means that the throttle can override the PAS and the PAS does not need to be started to activate the throttle.
P5 = 20 (power monitoring mode). I guessed at this and have no clue as to what this does other than setting the battery indicator on the display to actually show the battery level.

Any thoughts on these settings? I really appreciate any insight or comments that will help with this!

Best,

Lee