Custom ebike build: Mid-Drive or Hub?

[hoboin]

I want to replace my current commuter bike. It doesn't fit me well, but i now have around 7000 miles of riding to work since may 2021 and i think i have the bike to make a custom electric bike, i am just not sure which motor/battery i should go with, or if it will work with the bike i currently am looking to convert.

I am leaning towards either the bafang 750w or 1000w mid drive motor. My original electric bike had a weird mid-drive motor and i really liked the feel of that, but it was very old and annoying and had 2 chains. My modern Ariel Rider Rideal was great but i just don't like the slow response of the hub motor compared to the mid drive i had. But most importantly i want to be able to go up steep hills very fast. For my commute i have no choice but to use a road that is very steep and has no shoulder, with trees over hanging and a few turns.. very dangerous for bikes. On my Rideal, when pedaling my hardest, i can get to about 17mph and i am out of breath and sweating which i do not like. My older bike, i wouldn't even attempt it, i probably would go about 6mph to 8mph.

I really like having the ability to use the throttle only also, but 80 to 90% of the time i would like to pedal. Throttling from a dead stop or assisting up hill is when i generally use my electric bike.


My Body: 6 foot 3", 36" inseam. Chronic lower/upper back problems, scoliosis and herniated disc, hip problems and knee problems. my body can't handle hills really.

My Commute: 16 to 20 miles everyday. Northern Virginia, VERY HILLY, 2 monster hills to leave my neighborhood, one on a semi dangerous/steep tree lined road with no bike/walking lane and zero shoulder.

My Rideal, a few days ago when i hit 5000 miles at 5am.

Current/past e-bike:
Current: Ariel Rider Rideal, 750watt hub motor, 6 speed, small frame, mechanical brakes, regular fork.
Past: 2004 AeroEnvironment Charger, 250watt funky dual chain mid drive, 7 speed, small frame, v-brake & rollerbrake, regular fork

Bike i want to upgrade:
Framed Rendal- 21" frame
29"x2.1" tires
21 speed, crankset 42/34/24T, 7-speed 14-28t
100mm Suntour fork
Hydraulic disc brakes

Rendal Alloy - Mountain 29"

The Rendal was designed to take you from the neighborhood paths trails to the uptown streets. With the plush front suspension fork and durable alloy frame the Rendal is your ticket to endless adventure. Hydraulic disc brakes ensure full stopping power in any weather conditions you may encounter...

www.framedbikes.com

I have already replaced the handlebars with swept back ones, put on a stem riser and an adjustable stem, i'm looking for an upright riding style. I bought everything needed to swap out the cables/housing which will be a pain but it has to be done to raise the bars up how i would need it.

Questions:

1. Is bafang bbshd and bbs02 the best 2 options for mid drive at a reasonable price? I am seeing some bundles without batteries on walmart, $500 for the bbs02 and $800ish for the HD. Does anyone know of a better place to buy a complete set of components? Also is there a good place to buy batteries, or should i consdier buying the battery/motor all together?

2. Can anyone see any problem with my current bike that would not allow me to accept a mid-drive motor?

3. The bike's down tube has a really bad tapering to the top, almost like a triangle, where the bottom of the down tube is the thickest point, and the top of the downtube where the water bottle holder attachments are, is very thin. At the bottom it's about 3" thick, and at the top about 1/2". If i want to attach a battery to this point, does it matter if there is very little flat surface for the battery to install to?

 

[indianajo]

No mid-drive expert has contributed yet. I'm no help with that, I don't want to mess with the crank and my desire to machine steel is limited. I do pedal through floodwater sometimes and a hub motor is 4" higher than a mid-drive motor. I hate changing chains, too. After I did it at 5000 miles, the burglar took all my tools and I have to buy all three tools again before 5000 miles happens again.
Note none of your bikes pictured has a pie-plate 48 tooth rear sprocket. Before the mid-drive choir starts blathering about the advantages the gear train give to mid drives, calculate the torque multiplication of 46 drive 28 driven sprocket. 60% my audel millwright handbook tells me. That is a 40% torque reduction.
What's your gross weight? you, bike, accessories, lunch+kit. What is your max grade? Take a level and measure it. 7/8" rise in 6" length is 14.6%, my worst 100' grade. My Mac12t 1000 w 48 v geared hub motor would pull my bike at 330 lb gross authoritatively up that grade at 8 mph from a dead stop, or ~15 mph if I hit the bottom of the grade at that speed. The 12 windings push the torque curve down to the useable hill climbing range, instead of trying for max speed >25 mph with 10 windings. My Mac12t max speed on 26" wheels 2.1" tires was about 23 mph. You shouldn't have trouble in 20 miles overheating a geared hub motor. I ride 27 miles, up to 30 miles, with 77 hills the short way & ~100 the longer safer way. The mac could do it in 2 1/2 hours if I was in a hurry. Mid-drives do cool better on long slogs up the Sierras or Rockies; less warrenty repairs out there than hub drives.
With a high torque motor, make sure the torque arms are substantial and long. Mine are 4"x1"x12 ga cut out of high carbon bed frame rail. I use 1" wide sheet metal for clamps, not slotted hose clamps. My motor is on the front steel fork, leaving the 24 speeds my bike came with intact.
I use throttle exclusively, I hated the minimum speed and minimum acceleration of the PAS of my controller. However I pedal continuously, for exercise, except in situations like yesterday where the chain dropped off 8 blocks from home. I motored home slowly without pretending to pedal. Not an option with mid-drive. Throttle comes on mostly up steeper hills, or if the wind is >12 mph in my face. I sit upright in a high drag position, for back & neck health. I could ride the whole distance without power in 3.7 hours on low wind days in 2019, but not after 151 days of covid19 in 2020. I've got the time down from 6 hours spring 2021 to 4.1 hours yesterday with electric help. (Mac12t was destroyed by rain. Do not buy an ASI controller that has pins too close together to withstand rain. Rectangular white connectors for hall effect sensors & terminal strip phase wires are fine in rain under the seat)

 

[hoboin]

No mid-drive expert has contributed yet. I'm no help with that, I don't want to mess with the crank and my desire to machine steel is limited. I do pedal through floodwater sometimes and a hub motor is 4" higher than a mid-drive motor. I hate changing chains, too. After I did it at 5000 miles, the burglar took all my tools and I have to buy all three tools again before 5000 miles happens again.
Note none of your bikes pictured has a pie-plate 48 tooth rear sprocket. Before the mid-drive choir starts blathering about the advantages the gear train give to mid drives, calculate the torque multiplication of 46 drive 28 driven sprocket. 60% my audel millwright handbook tells me. That is a 40% torque reduction.

Never heard of this term, pie plate 48 tooth. Also not sure what you mean by the torque reduction, i will have to figure out those things. Does that mean i might want to consider changing out the drivetrain? I am not sure what goes into changing that out or if its worth it. Ideally i would have one shifter and not 2 shifter, i heard people talk about 11 speed but don't know if that is good for an electric bike with a mid drive.

What's your gross weight? you, bike, accessories, lunch+kit. What is your max grade? Take a level and measure it. 7/8" rise in 6" length is 14.6%, my worst 100' grade. My Mac12t 1000 w 48 v geared hub motor would pull my bike at 330 lb gross authoritatively up that grade at 8 mph from a dead stop, or ~15 mph if I hit the bottom of the grade at that speed. The 12 windings push the torque curve down to the useable hill climbing range, instead of trying for max speed >25 mph with 10 windings. My Mac12t max speed on 26" wheels 2.1" tires was about 23 mph. You shouldn't have trouble in 20 miles overheating a geared hub motor. I ride 27 miles, up to 30 miles, with 77 hills the short way & ~100 the longer safer way. The mac could do it in 2 1/2 hours if I was in a hurry. Mid-drives do cool better on long slogs up the Sierras or Rockies; less warrenty repairs out there than hub drives.

My gross weight is 205lb rider and 25lbs of gear. The bike weighs about 33lbs . I would probably use my Rideal as my grocery bike and keep the large basket on that and probably not do a large milk crate on the new bike, but i might want to use it for grocery runs also which would add another 25lbs or so, but that would be rare. Not sure on the max grade as of now.

With a high torque motor, make sure the torque arms are substantial and long. Mine are 4"x1"x12 ga cut out of high carbon bed frame rail. I use 1" wide sheet metal for clamps, not slotted hose clamps. My motor is on the front steel fork, leaving the 24 speeds my bike came with intact.
I use throttle exclusively, I hated the minimum speed and minimum acceleration of the PAS of my controller. However I pedal continuously, for exercise, except in situations like yesterday where the chain dropped off 8 blocks from home. I motored home slowly without pretending to pedal. Not an option with mid-drive. Throttle comes on mostly up steeper hills, or if the wind is >12 mph in my face. I sit upright in a high drag position, for back & neck health. I could ride the whole distance without power in 3.7 hours on low wind days in 2019, but not after 151 days of covid19 in 2020. I've got the time down from 6 hours spring 2021 to 4.1 hours yesterday with electric help. (Mac12t was destroyed by rain. Do not buy an ASI controller that has pins too close together to withstand rain. Rectangular white connectors for hall effect sensors & terminal strip phase wires are fine in rain under the seat)

Are most of your bikes hub motors? I also want to pedal continuously and use the throttle for hills. I forgot to mention i use an Eggrider to gain more power out of my motor and to be in more control over the different levels of assist. I mainly ride on bike trails on PAS level 2 and going 10 miles an hour, that is about what i like to go at, maybe a bit more like 12mph but on flats the battery/motor isn't being used, i mainly use it for hills.

Thanks for the reply!

 

[hoboin]

I just checked out Johnnynerdout's review on bafang's newer m625 option with the battery. That looks to be about $1200 for the complete setup of 19ah battery (it's huge) but that might be perfect to fit inside my large frame. I am not sure of a good source for batteries right now, anyone have any suggestion? I remember seeing people here suggest luna but most options seem to be out of stock. the BBSHD is going for about $800 without battery.

 

[harryS]

Wow, I've not been keeping up with the M-series, but there sure seems to be a bunch of motors out there from Bafang.
.
I've had the 750W BBS02B that came out in 2016. That's after they upgraded the controller not to blow up with 500W, and mine hasn't. I used to ride it like the OP with pedal assist off, and feathering in throttle for hills. Gotten older, and now it's PAS 1 at 12-14 mph, feathering in throttle as needed I did not want to get into adjusting/tuning so I did not get the programming cable, ALso wanted to keep the weight down, so I did not consider the BBSHD.
.
Used to ride the BBS02 a lot when I rode solo, but as my wife got into ebiking, the BBS02 was a little too fast for her, so we both ride hub motors..

 

[indianajo]

Pie plate 48 tooth are adjectives to the noun sprocket. Pies are about 10-11" in diameter, if you have never made one. Your biggest rear sprockets look like bog standard 28 tooth rear sprockets. Bosch standard drive sprocket is 46 tooth, I don't know about bafang. Using 46:28 low speed slows the mid drive motor down into the speed range where the torque curve has decreased. Also that ratio decreases torque by 40%. 28 tooth sprocket gears are not a big assist on hills, as some posters on here keep repeating. One of the loudest mid-drive fans sells mid drive bikes in California, where risk of over heating & burning a geared hub motor is significant. All a purchaser has to do is slog up a long grade slowly at max power for over an hour (according to Mac). Purchasing a 48 tooth rear sprocket cluster may not be an option for you, I've never seen one for 7 speed chain. Only for 10-11 speed chain, which is so thin chains wear out in 1500 miles when pedal pushers (road bike riders) use them. Electric mid drive bikes are worse on chains. Your front sprockets probably will not fit 11 speed chain.
I have one electric bike, with a front hub motor. I like riding it without power when I can, and geared hub motors don't drag with the power off. I've ridden it about 9500 miles since electrification. I bought the motor is for large headwind days, or when I'm wimpy, as I have been since 151 days of covid19, 51 days of delta & 13 days of BA5. Gross weight of 268 should put your ride into the class where a Mac12t would work. I don't have an egrider for more power. I did have a 25 A controller, until it errored out this spring. 3 1/2 years old. New controller is a wimpy 10 A, which will get me +tools + groceries up a hill with a wimpy bafang 500w hub motor ($36 + freight) but I have to pedal hard in 32:28 ratio or it stalls.
Main disadvantage to a Mac12t 48 v 1000 w is nobody in the US sells them anymore. I want another but the only ad I can find is for a pallet of 8 from alibaba. Mac Bldc Hub Motor 6t,8t,10t,12t,13t..16t - Buy Bldc Hub Motor,Bldc Hub Motor,E Bike Hub Moto24v Dc Gear Motor Product on Alibaba.com Lots of risks to buying direct from *****, besides I don't need 8 motors, I need one, or two. Geared hub motors I've been getting average life 3500 miles. Gears wore out on ebikeling motor ~4500 miles. Mac12t harness was melted by ASI controller in the rain, 3000 miles. Overheated a bafang 500w 36 v with a 48 v battery on too many hills, too long at max 500 w struggling up hills. ~500 miles. Using another $36 bafang 500w, deleted 23 hills & 3 miles from my route to ride State Route 3 dodging trucks & cars that won't give me room on the 8" berm by rolling into the grass. CHanging a geared hub motor in a built up wheel takes half the time of changing a chain.
Batteries, domestic supplier ebikeling seems to get few complaints. His geared hub motors now are only 750 watts 36 v, probably because of the problem of selling into CA, OR, WA, ID, MN, CO. California ebike reportedly resells EM3EV batteries with a good reputation. I bought my battery in 2018 from luna, who has exited the 48 v bike market. He sells 52 v batteries for racing in the Mojave desert, now.

 

[LLL]

My $0.02

I am your same size and weight, and also located in NoVa. I also own two Bafang mid drive bikes, 750 and 1000w.

I cannot answer your fitment questions, but I will say I think for road riding around here, even up pretty steep grades, the 750 is plenty fast and capable to move you at 30+ mph on the flats and if geared down for the hills properly, you can still easily go up the steepest roads I have found around here, without pedaling if you choose 20+ mph.

The super steep hills near me (private/restricted roads) are much steeper than I have ever found on a regular road in NoVa. I actively seek out steep roads to ride around here because I find them fun on the way back down trying to max out my speeds, and nothing would even get close to my testing grounds. On my testing circuit I ride, the 750 easily goes 10-15mph uphill (extreme) vs my 1000w 15-20mph.

It's hard to test out max uphill speed on my extreme hills using just the buttons due to the turns as I ascend which requires slowing to 10mph to avoid flying off the pavement.

The 1000w is nice for extreme uphill 45+ degrees) hitting the button, especially off-road when roots and rocks might hit the pedals, but the 750 does almost as well, just in a lower gear.

To be honest, I would have no issue swapping out my 1000w for a 750w at our size/weight. Both are stock, but the 1000w motor is much more noisey due to the metal gears and can get annoying on quiet trails. There is no PEEK gear yet available for the m620 (1000w) version.

Another thing to note is most m620s (1000w) are now CANBUS, but if you specify or look specifically for the UART version, they can still be had. The 750s are all still UART, so easy to tweek/tune and even upgrade to 1000w or more).

There is no CANBUS programming available yet, and I doubt it'll be available anytime soon, so choose wisely if you go with the 1000w.

I'll also add, both bikes I have are used off-road and on, and both are ridden across stream crossings, fully submerged at times, without issues, however I do not engage the motor while in the deep water.

 

[JRA]

$400 for a 19ah battery is not a bad price.

 

[tomjasz]

The BBSHD is a beast of burden

 

[tomjasz]

Main disadvantage to a Mac12t 48 v 1000 w is nobody in the US sells them anymore.

Shelley will sell 1 motor direct, “sample”. After which MOQ 8.

 

[tomjasz]

bafang 750w or 1000w mid drive motor.

I’d grab a BBSHD before that BS system the nerd reviewed becomes the norm. Proprietary battery, no ability to program, less and less DIY access seems the new direction. BBS01, BBS02B and BBSHD are quiet motors. I’d add a few parts to have handy.

 

[hoboin]

My $0.02

I am your same size and weight, and also located in NoVa. I also own two Bafang mid drive bikes, 750 and 1000w.

I cannot answer your fitment questions, but I will say I think for road riding around here, even up pretty steep grades, the 750 is plenty fast and capable to move you at 30+ mph on the flats and if geared down for the hills properly, you can still easily go up the steepest roads I have found around here, without pedaling if you choose 20+ mph.

That is good to hear, thank you so much for this info. Right now i live near wolftrap and travel to W&OD trail, and there are a few giant hills between where i live and the trail. Do you ever ride on that trail? I travel from vienna to falls church daily.

The super steep hills near me (private/restricted roads) are much steeper than I have ever found on a regular road in NoVa. I actively seek out steep roads to ride around here because I find them fun on the way back down trying to max out my speeds, and nothing would even get close to my testing grounds. On my testing circuit I ride, the 750 easily goes 10-15mph uphill (extreme) vs my 1000w 15-20mph.

It's hard to test out max uphill speed on my extreme hills using just the buttons due to the turns as I ascend which requires slowing to 10mph to avoid flying off the pavement.

The 1000w is nice for extreme uphill 45+ degrees) hitting the button, especially off-road when roots and rocks might hit the pedals, but the 750 does almost as well, just in a lower gear.

To be honest, I would have no issue swapping out my 1000w for a 750w at our size/weight. Both are stock, but the 1000w motor is much more noisey due to the metal gears and can get annoying on quiet trails. There is no PEEK gear yet available for the m620 (1000w) version.

Another thing to note is most m620s (1000w) are now CANBUS, but if you specify or look specifically for the UART version, they can still be had. The 750s are all still UART, so easy to tweek/tune and even upgrade to 1000w or more).

There is no CANBUS programming available yet, and I doubt it'll be available anytime soon, so choose wisely if you go with the 1000w.

I'll also add, both bikes I have are used off-road and on, and both are ridden across stream crossings, fully submerged at times, without issues, however I do not engage the motor while in the deep water.

Really great info. Sounds like the 750w could be very doable to save money. Not sure on the CANBUS vs UART info, will have to read about that.

Do you have any thoughts on my current drive train and if it would be suitable for a mid drive, or like the previous poster suggested maybe a 1000w front hub motor might be a good and cheaper option. But i would love to finally use a nice mid-drive.

 

[hoboin]

Pie plate 48 tooth are adjectives to the noun sprocket. Pies are about 10-11" in diameter, if you have never made one. Your biggest rear sprockets look like bog standard 28 tooth rear sprockets. Bosch standard drive sprocket is 46 tooth, I don't know about bafang. Using 46:28 low speed slows the mid drive motor down into the speed range where the torque curve has decreased. Also that ratio decreases torque by 40%. 28 tooth sprocket gears are not a big assist on hills, as some posters on here keep repeating. One of the loudest mid-drive fans sells mid drive bikes in California, where risk of over heating & burning a geared hub motor is significant. All a purchaser has to do is slog up a long grade slowly at max power for over an hour (according to Mac). Purchasing a 48 tooth rear sprocket cluster may not be an option for you, I've never seen one for 7 speed chain. Only for 10-11 speed chain, which is so thin chains wear out in 1500 miles when pedal pushers (road bike riders) use them. Electric mid drive bikes are worse on chains. Your front sprockets probably will not fit 11 speed chain.
I have one electric bike, with a front hub motor. I like riding it without power when I can, and geared hub motors don't drag with the power off. I've ridden it about 9500 miles since electrification. I bought the motor is for large headwind days, or when I'm wimpy, as I have been since 151 days of covid19, 51 days of delta & 13 days of BA5. Gross weight of 268 should put your ride into the class where a Mac12t would work. I don't have an egrider for more power. I did have a 25 A controller, until it errored out this spring. 3 1/2 years old. New controller is a wimpy 10 A, which will get me +tools + groceries up a hill with a wimpy bafang 500w hub motor ($36 + freight) but I have to pedal hard in 32:28 ratio or it stalls.
Main disadvantage to a Mac12t 48 v 1000 w is nobody in the US sells them anymore. I want another but the only ad I can find is for a pallet of 8 from alibaba. Mac Bldc Hub Motor 6t,8t,10t,12t,13t..16t - Buy Bldc Hub Motor,Bldc Hub Motor,E Bike Hub Moto24v Dc Gear Motor Product on Alibaba.com Lots of risks to buying direct from *****, besides I don't need 8 motors, I need one, or two. Geared hub motors I've been getting average life 3500 miles. Gears wore out on ebikeling motor ~4500 miles. Mac12t harness was melted by ASI controller in the rain, 3000 miles. Overheated a bafang 500w 36 v with a 48 v battery on too many hills, too long at max 500 w struggling up hills. ~500 miles. Using another $36 bafang 500w, deleted 23 hills & 3 miles from my route to ride State Route 3 dodging trucks & cars that won't give me room on the 8" berm by rolling into the grass. CHanging a geared hub motor in a built up wheel takes half the time of changing a chain.
Batteries, domestic supplier ebikeling seems to get few complaints. His geared hub motors now are only 750 watts 36 v, probably because of the problem of selling into CA, OR, WA, ID, MN, CO. California ebike reportedly resells EM3EV batteries with a good reputation. I bought my battery in 2018 from luna, who has exited the 48 v bike market. He sells 52 v batteries for racing in the Mojave desert, now.

Thanks a lot for your reply and info. I see what you are saying, it might be a better idea to go with a front hub motor. I will keep that in mind for sure, that would probably be the easiest way to go and cheapest.

 

[hoboin]

I am watching this and after biking for 5000+ miles with a hub motor, the biggest drawback is dealing with flats and changing brakes/tires on it. I had to replace a few tires in the wild and it was no fun at all, i feel like having a spare chain and putting that on is way less of a hassle than replacing a tube. Can't you just have a spare chain prepped at the correct length and ready to go and the fix would be like 1 to 2 minutes? I feel like that is less annoying than having to deal with a flat tire on a tricky rear hub bike.

 

[m@Robertson]

@hoboin ... Indianajo likes to - for whatever bizarre reason - deny the benefits of bicycle gears. His claims - made many times here and refuted as many times - can be tossed aside simply by recognizing that when you shift to a bigger cog in the back, it gets easier to pedal. Ignore the smokescreen around cog sizes or torque multiplication. None of that matters. You already know bigger (in back) is easier, as does anyone who has ridden a bicycle up a hill.

As a rule, if you have steep hills to deal with, a hub motor is out of its element - it is at a disadvantage. Why? Because it powers the bike thru the axle. That means it has no gears to help you get up a hill, and riding up a hill singlespeed sucks for the motor for all the same reasons it sucks for you if you tried it. That does not mean a hub motor cannot work for your needs, but its got its work cut out for it and you need to understand how you can use it to make do (for example, using 20" wheels to give the hub motor a torque advantage is not uncommon).

You mentioned a front hub motor. I'm actually a big fan of those, especially when they are coupled to a rear motor (either a mid drive or a hub). But if you are not being fancy, a front hub motor will still create a 2wd bike when you count your legs into the propulsion mix. Lots of people bag on front motors due to their poor relative traction - and this is a correct assertion if taken on its own. But if you add in your own ability to contribute power to a second wheel, a front hub motor is an EASY conversion option that is up for light duty.

But here's where a front motor falls on its face on your donor bike: You can NOT use anything but the weakest front hub motor with a suspension fork. Go to the DIY ebike forums and ask why and you will be showered with pictures of snapped fork dropouts and broken forks. No fork was ever designed to be pulled apart, which is what a hub motor wants to do. But the real risk are the snapped dropouts, regardless of whether or not you use what should be a required two torque arms. For a front hub motor of any substance, you want to use steel 1-piece forks with steel dropouts. There is one manufacturer of 2wd bikes who is using an RST Renegade fork on the front of their bike. That fork has extremely thick dropouts and also - I strongly suspect - they have neutered the power going to the front motor on the (likely correct) assumption that even a small boost up front coupled to a rear motor is going to be loved by the rider, and that lets them get away with murder.

For steep hills, the motor that will always be able to be fit for purpose is a mid drive. Your Framed Rendal looks very nearly an ideal candidate as well. The straight down tube lets you tuck the motor up against it, and you have a big (BIG) triangle that is going to make it easy to fit a battery bag and a nice triangle battery, or virtually whatever else you care to plug in... it will fit there.

If you want to spend your money only once, and make a bike that will take everything you can throw at it, you're going to want a mid drive. Your build's success will be in advance planning, although since you are starting out with a bike thats already built, you've got a lot of your work already done out of the gate.

And yes, he's reviewing my web site and its ebike build guide.

I’d grab a BBSHD before that BS system the nerd reviewed becomes the norm. Proprietary battery, no ability to program, less and less DIY access seems the new direction. BBS01, BBS02B and BBSHD are quiet motors. I’d add a few parts to have handy.

Yes, the M625 is a hot mess and there's no need to touch it. Bafang seems to be reconsidering their EOL'ing of the BBSHD. I have bought two of them in the last month. One from California Ebike and one from Luna Cycle, and I know both of them just came over on a boat from China. They are not new-old-stock ... current production. You'll pick up some of the details and the vibe from this.

.

 

[rich c]

With your list of ailments, personally I would not be investing in a new eBike. I'm about 1,000 miles short of my usual yearly riding due to medical problems this year. Believe me that with aging, cycling does not get easier on the body. Up steep hills, very fast, just shouldn't appear in a sentence together when talking about electric assist bicycles. Also with your distain for sweating and panting, wouldn't a motorcycle make a lot more sense?

 

[m@Robertson]

I got so wrapped up in countering the FUD I forgot to actually answer your questions:

Questions:

1. Is bafang bbshd and bbs02 the best 2 options for mid drive at a reasonable price? I am seeing some bundles without batteries on walmart, $500 for the bbs02 and $800ish for the HD. Does anyone know of a better place to buy a complete set of components? Also is there a good place to buy batteries, or should i consdier buying the battery/motor all together?

2. Can anyone see any problem with my current bike that would not allow me to accept a mid-drive motor?

3. The bike's down tube has a really bad tapering to the top, almost like a triangle, where the bottom of the down tube is the thickest point, and the top of the downtube where the water bottle holder attachments are, is very thin. At the bottom it's about 3" thick, and at the top about 1/2". If i want to attach a battery to this point, does it matter if there is very little flat surface for the battery to install to?

1. I would answer yes for the general consumer who wants a kit that has a ton of aftermarket support and gazillions of Youtube videos describing every possible tip and trick you can imagine and then some. The Tongsheng TSDZ2 is also a not-so-bad option but it is a bit rough around the edges and needs someone who knows how to counter its quirks and weak spots. Basically a BBS02 is enough to get you there and back, but it can be killed if you work it too hard. A BBSHD is the follow-on to the BBS02 and its chief benefit is it is beefed up everywhere. Don't just look at it as more powerful. Its more durable and unless you really try with aftermarket enhancements, you can't kill it.

I like to buy my HD motors from Luna Cycle. They are the lowest cost on the market from a reliable seller, and for me at least they are a completely known quantity. You can buy a complete install kit from them that includes everything. I also recently bought a BBSHD from California Ebike. I wasn't especially pleased with the fact it is limited to 28a instead of the 30a that the motor is capable of, and increasing to 30a via the usual settings interface is locked out. Plus the motor costs an additional $100. However they are a good vendor and I buy a lot of stuff from them. Just not BBSHDs usually.

You want a battery vendor? Bicycle Motor Works (dotcom) are a USA manufacturer (really) based in Pennsylvania. They also have some of the lowest pack prices for a quality pack that you can find. I have at least a half dozen of their retail packs and right now they are building another custom pack for me for a new project. Depending on the cells you choose their prices can be unbeatable. Note I am not counting junk Chinese vendors here. You can buy for hundreds less and roll the dice, safetywise.

2. It looks very nearly perfect at the angle you are showing it at. I will say that a 7-speed is a poor choice long term if that is a freewheel. Especially if you are only talking 28T which is a 1980's idea of a big cog. HOWEVER be advised that DNP makes a pretty decent 7speed cluster - as such things go - and I believe you can get 32T out of it. Long term when you get some money set aside, you want a Shimano cassette-bodied wheel so you can put on a long-cage 9 spd derailleur and a big rear cluster to go with it. Microshift Advent is inexpensive and durable. Its 9 spd cluster is all steel for durability and only costs about $39. The derailleur is I think $60 and the single-gear shifter tailored for ebikes is maybe another $30. But save that for later when you have decided you like the bike and want to upgrade it.

3. It makes no difference at all if you do it right. You want to do a triangle bag. Throw some closed-cell padding inside on the bottom to cushion the battery. You absolutely don't want to do a rivnut kind of thing and attach anything to the down tube for the reasons you describe. Here's a more involved way to do it: Go to Home Depot and get hold of some 1.5" aluminum bar that is 1/16" of an inch thick. Cut to size and thats your base 'plate' for the inside bottom of the triangle bag. Then lay down a strip of closed cell foam on top of that. Now you have a shock absorbing cushion that is fully stable and will not compress to the point where the battery is at risk thanks to the alloy shield. For your bike, very likely the ideal pack is the Falcon EV triangle battery bag (google it). Don't be scared by the primitive web site. they have been selling these things like this forever.

Given your stated desire to get up hills fast without working too hard, a mid drive should be the only thing you consider as its the only thing that can for sure do the job. But it won't be super fast. You will just be getting up the hill without exertion if you so choose. If you want fast going up a hill, you have to combine a mid drive and a hub. A mid alone is probably good for 15 mph with the right gears (you will be challenged by that 28T in back and will need to go small in front). If you go 2wd (solid front fork) then you can zoom up a long, steep hill at 20-25 mph. I do it with pedal assist but it could just as easily be on throttle.

Dual Motor AWD Electric Bikes – Case Study: Fat Trail and Hill Climber

Built to conquer the weakness of twin hubs in hills – and eliminate the damage a mid drive does to an ebike’s drivetrain. The bike I call 2Fat did all that.

talesontwowheels.com

If you want high speed up a hill with anything other than the above, you are talking about a 3-4 kw hub drive with a 72v, 80v or 96v monster battery. Essentially a motorcycle with pedals.

 

[hoboin]

With your list of ailments, personally I would not be investing in a new eBike. I'm about 1,000 miles short of my usual yearly riding due to medical problems this year. Believe me that with aging, cycling does not get easier on the body. Up steep hills, very fast, just shouldn't appear in a sentence together when talking about electric assist bicycles. Also with your distain for sweating and panting, wouldn't a motorcycle make a lot more sense?

Thank you for the consideration but honestly biking has changed my life so much, i can't imagine ever giving up biking for a motorcycle. Before i got into electric biking, i was in so much pain (most likely ankylosing spondylitis or arthritis related) i could not work for more than 6 hours, couldn't sit for more than 2 or 3 without severe pain and couldn't stand for more than 30 minutes or 10 minutes or so at a time. Now after a year of biking, all of my sitting and standing pain has gone away if i exercise every day. Because of my messed up knee and hips, regular biking without electric help is almost impossible. The bike i am trying to convert is a regular bike and i tried using it for fitness after biking for 1 year with electric assist and the pain in the knee returned like it does in most sports i do. So that is why i am trying to do this. I need to bike for about 1 to 2 hours a day in order to not have pain.

 

[hoboin]

I got so wrapped up in countering the FUD I forgot to actually answer your questions:

1. I would answer yes for the general consumer who wants a kit that has a ton of aftermarket support and gazillions of Youtube videos describing every possible tip and trick you can imagine and then some. The Tongsheng TSDZ2 is also a not-so-bad option but it is a bit rough around the edges and needs someone who knows how to counter its quirks and weak spots. Basically a BBS02 is enough to get you there and back, but it can be killed if you work it too hard. A BBSHD is the follow-on to the BBS02 and its chief benefit is it is beefed up everywhere. Don't just look at it as more powerful. Its more durable and unless you really try with aftermarket enhancements, you can't kill it.

I like to buy my HD motors from Luna Cycle. They are the lowest cost on the market from a reliable seller, and for me at least they are a completely known quantity. You can buy a complete install kit from them that includes everything. I also recently bought a BBSHD from California Ebike. I wasn't especially pleased with the fact it is limited to 28a instead of the 30a that the motor is capable of, and increasing to 30a via the usual settings interface is locked out. Plus the motor costs an additional $100. However they are a good vendor and I buy a lot of stuff from them. Just not BBSHDs usually.

You want a battery vendor? Bicycle Motor Works (dotcom) are a USA manufacturer (really) based in Pennsylvania. They also have some of the lowest pack prices for a quality pack that you can find. I have at least a half dozen of their retail packs and right now they are building another custom pack for me for a new project. Depending on the cells you choose their prices can be unbeatable. Note I am not counting junk Chinese vendors here. You can buy for hundreds less and roll the dice, safetywise.

2. It looks very nearly perfect at the angle you are showing it at. I will say that a 7-speed is a poor choice long term if that is a freewheel. Especially if you are only talking 28T which is a 1980's idea of a big cog. HOWEVER be advised that DNP makes a pretty decent 7speed cluster - as such things go - and I believe you can get 32T out of it. Long term when you get some money set aside, you want a Shimano cassette-bodied wheel so you can put on a long-cage 9 spd derailleur and a big rear cluster to go with it. Microshift Advent is inexpensive and durable. Its 9 spd cluster is all steel for durability and only costs about $39. The derailleur is I think $60 and the single-gear shifter tailored for ebikes is maybe another $30. But save that for later when you have decided you like the bike and want to upgrade it.

3. It makes no difference at all if you do it right. You want to do a triangle bag. Throw some closed-cell padding inside on the bottom to cushion the battery. You absolutely don't want to do a rivnut kind of thing and attach anything to the down tube for the reasons you describe. Here's a more involved way to do it: Go to Home Depot and get hold of some 1.5" aluminum bar that is 1/16" of an inch thick. Cut to size and thats your base 'plate' for the inside bottom of the triangle bag. Then lay down a strip of closed cell foam on top of that. Now you have a shock absorbing cushion that is fully stable and will not comporess to the point where the battery is at risk thanks to the alloy shield. For your bike, very likely the ideal pack is the Falcon EV triangle battery bag (google it). Don't be scared by the primitive web site. they have been selling these things like this forever.

Thanks so much for your detailed replies, i will think about all this and ask follow up questions later. Really appreciate all of this

 

[tomjasz]

They are the lowest cost

Highest margin. Good for best prices but sadly make competition difficult. I get it. But supporting this irritates me.