Will this bike break if converted to ebike?

Sometimes there are benefits to being a volunteer, nothing to be ashamed off. Especially since it's a direct trade off, you help others who in turn can enjoy part of the program which you enjoy less anyway.

I bet you got plenty of stories :)
Where I used to reside in California the police department would have the bike club fix up the unclaimed bikes to give away.
Most were gifts at Christmas but there would always be inventory if there was any needs during the year.
Ashamed to help out ? Not in the least.
 
Where I used to reside in California the police department would have the bike club fix up the unclaimed bikes to give away.
Most were gifts at Christmas but there would always be inventory if there was any needs during the year.
Ashamed to help out ? Not in the least.
Hey, you've probably heard this before Steve, but thanks for doing that for others.
 
Sounds like BM this year was a bit of a nightmare, the guy who told me that it 'definitely could rain in the dessert' couldn't have been more right.

Hope everyone got out all right ( still getting out / stuck? ).
 
, the guy who told me that it 'definitely could rain in the dessert' couldn't have been more right.
Oh, it definitely rains in the desert(s). I live in a (set of) city(ies) in the middle of one, and it certainly rains here...not often, but can have flash floods when it does. The last few years, I have twice had to ride thru water that was more than a foot deep on the way home, with the SB Cruiser trike. Normally it's nowhere near that bad...but it can be. This year has been much drier and hotter than usual for us, so hardly had to ride thru any rain at all, and barely seen puddles on the road during any of it.
 
I always found it rather fascinating that once you have a drought, rain can actually be more harmful then before. Dry ground and runoff and all that. It's just that we don't have any of that around here so it is hard to imagine. I guess the closest I been to a desert is Spain.. and that's not even the part which actually is classified as a desert as I've not ventured much further down then Barca / Girona region.

A foot of water is twice the depth required for fast flowing water to drag a person off his feet afaik and if my math conversions are on point. That's also what I would be the most scared off, in my mind a desert is mostly flat and thus wouldn't obstruct flow compared to say a forest floor or even a meadow like terrain, so flash floods in a dessert sound to me much more dangerous quickly then in other regions.
 
Hey, I have an update (and two new challenges here).

Quick Update: I ordered the TSDZ2B Tongsheng 48V 500W 350W 15A mid-drive motor because the front and rear seemed like poor options (bike has coaster brakes so I can't replace the back wheel and the front wheel is not stable enough for motor torque... also the wheels look cool, so replacing them wouldn't really be ideal). I spent 4 hours filing down parts of the motor - probably not the best idea, but I got it to fit!

Current Challenges:
- The chain won't stay on the chain ring where the peddle is, it keeps falling off right away, even when peddling manually
- My assumption is this is because the chain is now about an inch further away from the bike frame because of the motor (see photos). Other people have confirmed this is likely the cause of my issue.

The chain not staying on is the biggest issue.

The second issue is that I can't brake.

I had assumed, wrongly, that this motor would allow me to use the bike's coaster brakes.

Putting traditional brakes on this bike doesn't seem like a good option. I don't see a good place to attach them without removing the fenders, which would ruin the look.

So right now I'm leaning towards taking out the motor and reverting back to full manual, but before I did that and gave up completely I figured I'd see you have any ideas.

Again, photos of the situation with the chain attached.
 

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That’s a 120mm rear, yes?

I’d spread the rear triangle for a 135mm drum or roller brake wheel. The drum/roller solves the brake issue, and moves the freewheel 7.5mm outboard to help alleviate the chainline problem.

A narrow-wide chainring with 10sp chain should then suffice to retain the chain. If not, add a chain guide.
 
That’s a 120mm rear, yes?

I’d spread the rear triangle for a 135mm drum or roller brake wheel. The drum/roller solves the brake issue, and moves the freewheel 7.5mm outboard to help alleviate the chainline problem.

Coaster brake wheels are typically 110mm wide.

A narrow-wide chainring with 10sp chain should then suffice to retain the chain. If not, add a chain guide.

Good God, that would be an atrocity on a lowrider bike. This is a single speed, 144 spoke rear wheel we're discussing. Electrifying it is already a very dubious thing to do. Putting a 135mm cassette wheel and derailleur on a bike with rear opening 110mm dropouts and no hanger is a bizarre choice in any case, but it would sacrifice the only thing a lowrider bike has going for it: looking good mang.

 
110mm is even better with regards to improving chainline via wider hub.

I wouldn’t advise a cassette or derailleur either. I said 10sp chain, because it meshes better with narrow wide chainrings. All I suggested was using a roller braked hub. Use a 3sp one if that’s all that’s available, and run it as a single speed.

I’m not the philistine who put a mid-motor on this bike, just the guy helping tidy up the mess.

Sorry Brett, I’m joking. You’re giving the bike a second life. Do whatever you want with it. But you have to get that chainline sorted, one way or another.
 
The chain not staying on is the biggest issue.

The second issue is that I can't brake.

I had assumed, wrongly, that this motor would allow me to use the bike's coaster brakes.

As someone else noted, there is a coaster brake version of the TSDZ2 system. I'm not sure but I think it is just one part (a clutch?) inside the unit that makes it that, and possibly a firmware change. You might check with your seller or TongSheng to see if they have a "kit" of parts to convert yours to that.

But you are still left with the chainline problem; I don't know a good way to solve that that wouldn't require major changes to the bike itself, changing it's looks and functionality. (EDIT: As Chalo points out below, there are replacement chainrings for the TSDZ2 that will help some)

One possible way that would not make much of a change, but would look wierd and might not work:

You *might* be able to make a nylon "deflector" wedge that mounts to the stay/frame somewhere between the rear hub and the front chainring, to push the top of the chainline over to the right to line up with the top of the chainring.

You may then need a similar wedge the other direction below it to force the bottom of the chainline over to the left to line up with the bottom of the rear sprocket.

It'll make noise, but it might work if the angle of the wedge is shallow enough and the wedge is long enough and in the right spot.


If you haven't noticed it, you need a new chain, too--you have a broken link that's sideplate has separated from it's pin (might be fixable but given the condition of the chain is better to replace anyway).
 
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110mm is even better with regards to improving chainline via wider hub.

I wouldn’t advise a cassette or derailleur either. I said 10sp chain, because it meshes better with narrow wide chainrings. All I suggested was using a roller braked hub. Use a 3sp one if that’s all that’s available, and run it as a single speed.

Single speed chain drives don't have to retain their chains. Not having slack in the chain does that. But in regard to spacing, you're on the right track for sure.

There are deep offset sprockets available (for fat tire chopper bikes and such) that allow better chainline management than the +/- 2mm that a typical coaster brake sprocket offers. Here's one:


If one of these doesn't offer enough offset, then an added measure is to add spacing (like an axle nut put on backwards) to the left side of the hub, widen the rear triangle by that amount, and dish the wheel back to its new center.
 
Still, if correcting the chainline to a sufficient degree proves impractical, narrow-wide chainring and chainguide would help, and doesn’t impinge the aesthetics.

I didn’t realise preserving the 144 spokes was important. That changes things, for sure.

And might mean having to install a rear calliper brake if the motor-coaster modifications that AW presented aren’t realisable.
 
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