Hello! and I think I want to build my very first ebike(compact cargo)!

Perhaps you know the answer- PedalUma posted above that I need a bottom bracket socket. Is that the same as the bottom bracket removal tool/bottom bracket tool(which I think are the same)? Some tools look similar but are not, some tools have different names but are the same....
The answer is 'maybe' :) It will depend on what bottom bracket you have, and what tool your motor needs. Both will vary. All bottom bracket removal tools are sockets of one sort or another. Some are 12-pt. some 16 and there are many variations in between - that vary in diameters and more. You just have to buy the right one for your own BB. Same goes for the motor. The cvhances of needing the same tool for the motor and for the bottom bracket are, I think, slim. But hey who knows until you get down into it and see.
 
From my experience of converting (nearly a dozen of) bicycles into ebike since 2013;
I can say that (for your purpose) getting a complete ebike straight from manufacture would be much less hassle & likely cost much less than trying to find a donor bicycle/frame and convert to an ebike.

Even if you have to change out the stock crankset for shorter cranks and perform other mods to make the ebike suit you specifically.

My Fiido T1 cost $1499 with free shipping, modify stem/handlebar/grips/crankset/seatpost/seat, all combined less than $200.

Personally, I would have started planning in the winter time and made the purchase for ebike & parts prior to the riding season.
Because right now, at the height of cycling season, unless stores have them in stock and ready to move; anything that needs to be ordered will be longer than expected.
I have the donor bike already- Tern Short Haul (same frame w/slightly lower specs of a Quick Haul w/Bosch mid drive) I plan to attach the Tongsheng mid drive onto the Short Haul. The only changes to make is the handlebar and maybe the cranks and stem.
The Short Haul is the shortest length cargo bike I could find w/large carrying capacity and being able to stand vertically is a huge plus! I do like the hefty Fiido T1 frame but its too long and heavy and preferred a mid drive vs hub motor.
 
The answer is 'maybe' :) It will depend on what bottom bracket you have, and what tool your motor needs. Both will vary. All bottom bracket removal tools are sockets of one sort or another. Some are 12-pt. some 16 and there are many variations in between - that vary in diameters and more. You just have to buy the right one for your own BB. Same goes for the motor. The cvhances of needing the same tool for the motor and for the bottom bracket are, I think, slim. But hey who knows until you get down into it and see.
Ok. After poking around Park Tools website I better understand your "maybe"...

The Short Haul specs BB is FSA cartridge, sealed bearings. Measured BB 73mm length. Per Park Tools site- FSA are threaded. Roughly measured BB 34mm diameter but will remove the cranks for a proper measurement of major/minor diameter and to count the notches.
 
Ok. After poking around Park Tools website I better understand your "maybe"...

The Short Haul specs BB is FSA cartridge, sealed bearings. Measured BB 73mm length. Per Park Tools site- FSA are threaded. Roughly measured BB 34mm diameter but will remove the cranks for a proper measurement of major/minor diameter and to count the notches.
That sounds like what is commonly called a standard English threaded bottom bracket. Should be straightforward to remove with the right tool. For sizing the motor, the bottom bracket width (the empty tube once you remove the bottom bracket+spindle - and yes they are both called the same thing - will have to match your motor. So if you have a 68-73mm bottom bracket, your motor has to be made to fit that. If its a 100mm bracket you need a 100mm motor. For fat bikes, due to the wide chainstays, its common to use a 120mm motor and then put spacers on the drive side to get the secondary housing to clear. Probably not something you need to concern yourself with.
 
That sounds like what is commonly called a standard English threaded bottom bracket. Should be straightforward to remove with the right tool. For sizing the motor, the bottom bracket width (the empty tube once you remove the bottom bracket+spindle - and yes they are both called the same thing - will have to match your motor. So if you have a 68-73mm bottom bracket, your motor has to be made to fit that. If its a 100mm bracket you need a 100mm motor. For fat bikes, due to the wide chainstays, its common to use a 120mm motor and then put spacers on the drive side to get the secondary housing to clear. Probably not something you need to concern yourself with.
I ordered the PT crank remover and changed out the handlebars- swept back with a nice rise and 22.5" wide. Feels great.
Do I need to consider Q factor- change out pedals to reduce it? I plan to switch pedals to either 155 or 160mm. Should I seek out pedals that specifically reduce q factor?
Chain ring- want to swap for a 52T. Does it need to be a offset chain ring?
Donor bike is 20" w/8 gear and would like to be able to reach 28mph but not sure if its possible. The Tern Quick Haul (electrified version of my donor bike) has 9 gears and is a class 3 (28 mph).
 
Do I need to consider Q factor- change out pedals to reduce it?
Quack Factor comes from the crankarms, not the pedals, although putting your foot half on and half off will increase it thataway :) Only you will know whether or not your pedal width is comfortable. After MANY years of cycling with knee pain, I discovered entirely by accident I could make that pain go away with pedal spacers (which contradicts what I just said about crankarms but never mind that) and for me a very wide Q is a good thing. But the last couple of bikes I have built don't do the spacers and so far my knees have stayed good.

I plan to switch pedals to either 155 or 160mm. Should I seek out pedals that specifically reduce q factor?
See above. I just ordered a set of Minerva crankarms for one of my bikes and they came in three separate Q values.
What you should be paying attention to is whether or not the pedals are centered underneath your butt. A typical mid drive will kick the drive side pedal out some - wider. Thats why special crankarms like Lekkies and the crappy stock Bafangs have a left offset of 18mm - they have an outboard offset that moves the pedal out by that far to even the pedals up underneath you.
Chain ring- want to swap for a 52T. Does it need to be a offset chain ring?
Almost certainly yes. Chain alignment is a big deal. Here add this to your reading list. It covers the pedal alignment topic in considerable detail, along with stuff like chain alignment, and there is a separate topic entitled 'Musical Chainrings' that will go deeper into the chainring thing.


BTW a 52T chainring is almost always the wrong answer. Which of course leads me to link another article:


Donor bike is 20" w/8 gear and would like to be able to reach 28mph but not sure if its possible. The Tern Quick Haul (electrified version of my donor bike) has 9 gears and is a class 3 (28 mph).
It will all depend on your gears - and your body weight. Some people report 35mph speeds and some 25 mph. The 250 lb guys... 3 guesses which speed they get :) I can reach 32 mph without issue on my Stormtrooper., which is a fat bike with a single BBSHD and a 42T front ring and a 14T on the back. I also have a 12T but using it bogs the motor.
 
Quack Factor comes from the crankarms, not the pedals, although putting your foot half on and half off will increase it thataway :) Only you will know whether or not your pedal width is comfortable. After MANY years of cycling with knee pain, I discovered entirely by accident I could make that pain go away with pedal spacers (which contradicts what I just said about crankarms but never mind that) and for me a very wide Q is a good thing. But the last couple of bikes I have built don't do the spacers and so far my knees have stayed good.


See above. I just ordered a set of Minerva crankarms for one of my bikes and they came in three separate Q values.
What you should be paying attention to is whether or not the pedals are centered underneath your butt. A typical mid drive will kick the drive side pedal out some - wider. Thats why special crankarms like Lekkies and the crappy stock Bafangs have a left offset of 18mm - they have an outboard offset that moves the pedal out by that far to even the pedals up underneath you.

Almost certainly yes. Chain alignment is a big deal. Here add this to your reading list. It covers the pedal alignment topic in considerable detail, along with stuff like chain alignment, and there is a separate topic entitled 'Musical Chainrings' that will go deeper into the chainring thing.


BTW a 52T chainring is almost always the wrong answer. Which of course leads me to link another article:



It will all depend on your gears - and your body weight. Some people report 35mph speeds and some 25 mph. The 250 lb guys... 3 guesses which speed they get :) I can reach 32 mph without issue on my Stormtrooper., which is a fat bike with a single BBSHD and a 42T front ring and a 14T on the back. I also have a 12T but using it bogs the motor.

Quack Factor comes from the crankarms, not the pedals, although putting your foot half on and half off will increase it thataway :) Only you will know whether or not your pedal width is comfortable. After MANY years of cycling with knee pain, I discovered entirely by accident I could make that pain go away with pedal spacers (which contradicts what I just said about crankarms but never mind that) and for me a very wide Q is a good thing. But the last couple of bikes I have built don't do the spacers and so far my knees have stayed good.


See above. I just ordered a set of Minerva crankarms for one of my bikes and they came in three separate Q values.
What you should be paying attention to is whether or not the pedals are centered underneath your butt. A typical mid drive will kick the drive side pedal out some - wider. Thats why special crankarms like Lekkies and the crappy stock Bafangs have a left offset of 18mm - they have an outboard offset that moves the pedal out by that far to even the pedals up underneath you.

Almost certainly yes. Chain alignment is a big deal. Here add this to your reading list. It covers the pedal alignment topic in considerable detail, along with stuff like chain alignment, and there is a separate topic entitled 'Musical Chainrings' that will go deeper into the chainring thing.


BTW a 52T chainring is almost always the wrong answer. Which of course leads me to link another article:



It will all depend on your gears - and your body weight. Some people report 35mph speeds and some 25 mph. The 250 lb guys... 3 guesses which speed they get :) I can reach 32 mph without issue on my Stormtrooper., which is a fat bike with a single BBSHD and a 42T front ring and a 14T on the back. I also have a 12T but using it bogs the motor.
This donor bike has a 52T chain ring and 11-34 cassette. I weigh about 112-115 lbs depending on the seasonal attire. This bike is for city riding car lite/free living. Not pancake flat but not super hilly either. There are some super hilly places but I will avoid as needed.
 
Update- I’ve removed the bottom bracket and have the motor.

Tried fitting but it only goes in part way.

Original bb screws in and the body of it is slightly narrower than the width of threaded end.

The tsdz2b is slightly narrower than the width of original bb threads but is getting stuck.

Issue- I feel like it’s getting stuck or snagged inside even before hitting the braze on.
The braze on at the bottom is bulky w/ugly weld.

What is the best way to reduce the braze on? Grind with angle grinder?
 

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The middle section of the frame's BB shell is 2mm thicker than at the threads. I would use a bastard file with a flat side and a rounded side. Use the rounded side. The cable guide can be removed with a hacksaw blade, filed, and touched with taupe nail polish. Move the shift housing to the right and over the BB shell and the brake to the left and over the BB shell before inserting the motor.
 
Got my first ebike experience riding the NYC Citi ebikes around Central Park- it was a blast and now I must have one!

I'm short (5'2"), 28.5" inseam about 115 lbs. Looking to build a compact cargo bike for city (car free/lite) living/hauling/commuting, the more "diy" it looks- the better since I want to actually use it/lock it with less fear of it being stolen. I live in Los Angles with near perfect weather for bike riding but no infrastructure for bike riding/parking... so prefer a Class 3 with throttle for crossing intersections/quick acceleration on unavoidable stroads but mostly ride on residential roads wherever possible to stay alive. LA has varied terrain- flats/hills, smooth/potholed.

Wants- compact length (live in tiny apartment) with step thru frame, Class 3 (or close) with throttle and WALK mode (have few steps to go up), hydraulic disc brakes preferred, sturdy rear/front racks, integrated lights, either a front hub or mid drive (still contemplating along with torque/cadence) with either 20" or 26" wheels, open to IGH or derailleur.

Want to build a reliable, easy to repair, novice diy friendly build for mostly pedaling w/assist vs throttle/scooter riding.

If hub build- front hub for easier access, will use front rack to balance weight so most of the weight isn't on the rear wheel and hopefully the chunky look is off putting.

If mid drive- leaning towards Tonsheng TSDZ2B for the torque sensor but read its better NOT to connect throttle+ rather use it as a temp sensor since it's prone to overheating? Power to lights are very low- not ideal for powering bright front/rear lights? OSF vs stock- If I flash, it voids warranty or pay $175 more to buy already flashed but shorter warranty (worth it?) or wait 1 year and then learn to flash? Q factor- need to change crank arm.

Bafang mid drive is cadence only, harder on the chain/derailleur b/c its more powerful?

Ideal frame- Cero One, Cycle truck, donky bike, Omnium(mini) with 20" front tire/26" rear tire or Yuba style 26" front/20" rear or Tern Quick Haul/Rei Coop Cargo/Benno demi for the easy step thru, upright seating posture, low center of gravity/stable for carrying stuff.

Donor frame- Tern Short Haul (1K) hydraulic brakes, rear rack that allows vertical standing, step thru etc. Still need to test ride it...
Raleigh Lorry (700) mechanical brakes, front rack, lesser components, cycle truck style, no rear rack :(
Terry road bike w/mixte frame into cycle truck- if I can find one, buy clydesdale cargo fork, upgrade rim to disc brakes?
Vintage xs steel touring w/step thru frame into cycle truck- if I can find one, buy clydesdale cargo fork, upgrade rim to disc brakes?

Currently ride with 150mm cranks on 20" wheels, previous bike had 170mm on 29" wheels- much prefer the 150mm.

Think the best/straightforward but most $$$ diy is the Tern Short Haul since it has hauling capability/hydraulic brakes etc and just need to build attachment to hold battery. I will remove decals and throw paint/stickers to uglify.

Suggestions??? Words of wisdom???
Howdy,
I am an Oldtimer semi retired Businessman. One of the many things I learned the World over, if a thing is not secured it gets lost or stolen. North America including Canada is especially bad for Theft. Therefore if I would leave my eBike even for a minute alone where I cant see it and get to it within a second, I lock it onto something with at least 2 different devices plus Bike Alarm.
Better safe then sorry - UC
 
Update- I used hacksaw to remove the cable guide but did some damage to the bb frame 🤬.
Note to self- don’t use dull hacksaw in low light at a bad sight angle.
I’m ended up taking off some of the frame of the bb.
Here is a photo- did I ruin the structural integrity? I’m so mad at myself😩.
Positive note- the tonsheng slides in the bb! It was just the cable guide preventing the install.
 

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Here is a photo- did I ruin the structural integrity?

I think you'll be fine.
What's done is done.
I think that you should just install the motor and keep an eye on the bottom bracket.
If any cracks develop, it should crack the paint too.
It looks like the motor connects to the other side where most of the stress probably is.

You should be able to see that area clearly when it's assembled and keep checking for looseness or any wobble developing.
 
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I think that you should drill a weep hole in the bottom bracket while you've got it apart.
Check to see if your frame has any weep holes.

Your frame tubes may channel water into the bottom bracket.

I drilled mine for good measure.

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I think that you should drill a weep hole in the bottom bracket while you've got it apart.
Check to see if your frame has any weep holes.

Your frame tubes may channel water into the bottom bracket.

I drilled mine for good measure.

View attachment 158007View attachment 158008
I'll look for drain holes but I'm not confident to make a hole in the frame especially after accidentally sawing part of the bb frame off. There are no open holes in the frame to let water in- no internal cabling. Would I still need drain holes if the frame has no holes to let water in?
 
Would I still need drain holes if the frame has no holes to let water in?

It's possible.
My ebike lets water get past the battery and bottom battery bracket and feeds it right into the bottom bracket.

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I wouldn't drill any holes in the bottom bracket. Think of all the zillions of bikes that don't do that and get by just fine. The kind of drainage problem that @PCeBiker is talking about comes from a unique frame design flaw, where the manufacturer actually created a place for water to collect ... and then put a hole in the frame so it could drain inside.
 
First ebike conversion COMPLETED!!!!!
Many thanks to all here, especially to PedalUma for his guidance and patience!

Peppered him with lots of questions!

It all fits! Works! And looks great!

Also discovered I’m more of a masher than a spinner :(

I’m learning to be a spinner- any tips appreciated!

YouTube tells me I need to do sprints and timed trials…is that necessary for learning to be a spinner on a cargo bike?

I just want to be kind to the motor and for it to last.

Gotta get lights, accessories and a big fat angle grinder resistant d lock!
 

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