Can a 1000w mid drive do hills, or does it always needs MTB gearing to get high Nm?

duggie

Member
Region
United Kingdom
Re. my Kettles bike. I'm now in contact with the seller who seems ok and wants to help, so I think in due course I'll have the bike working again. I learnt not to take the bike to it's limit. You'd think that there would be some kind of safety cut out, which I don't think there is. Also, I learnt that there are masses of controllers and with all sorts of connectors and wires; I couldn't find one the same anywhere, so being able to replace a controller should be a concern when buying a bike.

Anyway, what I am hoping to learn now is this: I have a little folding bike, an apollo 1656280470956.pngand I am thinking of converting it to an ebike with a bafang 1000w, the spec in this motor says it has a max of 160Nm. I think this sounds good and may then be able to get me up this steep hill problem I have with no effort. What do folks think? I see mountain bikes with extra massive cogs at the rear and little cogs at the crank, and maybe, actually, it is this cog arrangement which actually does the business, and so this folding bike with a 1000w motor will still not be able to deliver the Nm to get up the hill. Of course there will be something in my thinking, but would that 1000w mid drive and the bike in first gear be able to pull some serious Nm. What you folks think?
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
I think there's a lot to this - including just how fast you want/need to be moving to climb this hill. Mid drives, especially big ones, are well known for their versatility. That's not to say though, that bigger (1000w+) are necessary vs. the ability of a smaller (say 250w) when placed in "granny" gear. They'll both climb about anything. The difference will be how fast they're going when doing that.

Weight involved may also be a factor.
 

duggie

Member
Region
United Kingdom
AHicks......... I put a bafang 250w onto my girlfriend's Apollo folding bike. The spec says it has a max of 61Nm. It's not enough to do the hill. The 1000w has max 160Nm, it says. The thing is that this hill is steep. I'm not bothered about speed. I can pedal and it helps a lot, but it's just knackering doing this hill. I just want to press a thumb throttle and slowly be transported up the hill with no effort at all.....haha, sounds terrible when i say it how it is. But I'm in my late 50s and only going to get older, and it is that what I am thinking about as I want to keep going to my allotment for another twenty years. I'm tall and 15 stone. It seems a lot to ask a motor to do, but then i see old folks mobility scooters climbing steep hills no problem. I couldn't use one because of a narrow muddy path I have to travel. Surely 160Nm would do the trick. I don't want to pedal. You say a 250 will climb about anything, but you must be meaning with also pedalling?

GazelleRider.......you must be fitter than me, I can't be doing with all that pedalling. I do like to pedal but on the flat at a pleasant sedate rate of total ease and joy.
 

GazelleRider

New Member
Region
Canada
Hi Duggie

When started looking into e-bikes we too at first thought that we wanted high powered, throttle bikes. We are 70 and 67 years old and realized that what keeps people young is a bit of exercise, which is more likely to do if it's easy. Suggest you test ride lots of types of bikes before you buy!

Pedalling even a 250 W mid drive bike up a hill in low gear is easy - Test ride some - We tested lots of Bafang, Shimano, Yamaha, Brose etc. bikes. We found that the Bosch mid-drives are very smooth and that you really want a bike with torque sensing (not just cadence sensing like many throttle bikes have) if you are riding on trails with lots of other traffic and need to be able to constantly and subtly adjust your speed to match others. Even 250 W 65 Nm bikes are capable of magnifying your pedal input 3.5 times. That's a lot of hill climbing power when applied through the gears.

By the way, I'm in Engineering and the way that e-bike "Power" is rated is almost meaningless ( in practice it's related to how hot the motor can get) and test methods differ hugely from manufacturer to manufacturer. They also slant the results to get in under the Euro 250 watt limits.

You will find that it's quite a joy to have just enough power to make you feel like pedalling, just because it's pleasant. My 70 year old wife says that she feels like she is flying when riding her bike, it's so easy.
 

ElevenAD

Well-Known Member
A1000watt Bafang mid drive will take you up anyhill, you decide how much effort you want to exert via the Pedal assist level selector or you could just throttle up the hill if thats what you want to do, they are well built and very capable motors.
 

tomjasz

Well-Known Member
The BBSHD is a beast of burden. I found them to be personally overboard but sold and supported more than I can account for. Reliable and powerful. You’ll climb any hill much faster than I can with my 250W or 350W bbs01’s.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
AHicks......... I put a bafang 250w onto my girlfriend's Apollo folding bike. The spec says it has a max of 61Nm. It's not enough to do the hill. The 1000w has max 160Nm, it says. The thing is that this hill is steep. I'm not bothered about speed. I can pedal and it helps a lot, but it's just knackering doing this hill. I just want to press a thumb throttle and slowly be transported up the hill with no effort at all.....haha, sounds terrible when i say it how it is. But I'm in my late 50s and only going to get older, and it is that what I am thinking about as I want to keep going to my allotment for another twenty years. I'm tall and 15 stone. It seems a lot to ask a motor to do, but then i see old folks mobility scooters climbing steep hills no problem. I couldn't use one because of a narrow muddy path I have to travel. Surely 160Nm would do the trick. I don't want to pedal. You say a 250 will climb about anything, but you must be meaning with also pedalling?

GazelleRider.......you must be fitter than me, I can't be doing with all that pedalling. I do like to pedal but on the flat at a pleasant sedate rate of total ease and joy.
You simply cannot compare a Bafang 250w geared hub output, to the same size mid drive motor. The mid drive (any size) will have a HUGE advantage as the power is run through the gears in back, where the geared hub drive is going to be fixed at 5:1. Spend some time on that concept if you need to, it's a really big deal when it comes to climbing hills.....

I missed the part where you don't want to peddle in your first note. That being the case, go ahead with the 160nm motor. If that won't do what you want to do, nothing will....

I'm sure you're aware of the legalities of running an e-bike in the UK (if not you had better look into it). That in mind, do you think you could get away with a big Bafang mid drive? Are the rules enforced?
 

retiredNH

Well-Known Member
Region
USA
Oh, stop! Don't be a Stefan! You're beginning to remind me of...
If only we were all as able as you! I've come to enjoy and look forward to your commentary, but this just continues to astound me.
Sorry. Didn't mean to offend. Why do you take issue with the statement? I can understand how some folks want a throttle to help get started. I can understand how some of our fellow posters have had life altering health events, like I have (and have posted about) that raise the need for more riding assistance. What I have a hard time understanding is how someone like the OP can want to power up hills without pedaling at all. Is that biking?
 

indianajo

Well-Known Member
You simply cannot compare a Bafang 250w geared hub output, to the same size mid drive motor. The mid drive (any size) will have a HUGE advantage as the power is run through the gears in back, where the geared hub drive is going to be fixed at 5:1. Spend some time on that concept if you need to, it's a really big deal when it comes to climbing hills.....
This fantasy persists all over electricbikereview forum. Mid drives have usually a 46 tooth sprocket or so. They have some internal gearing, but the quoted torque is at the drive chain ring. For a mid drive to get torque multiplication "through the gears in the back", the largest rear sprocket has to be bigger than the front. The stock bafang 1000w chainring is 46 tooth. https://bafangusadirect.com/collect...bafang-1000w-bbshd-mid-drive-ebike-motor-kit# That means to get any torque multiplication from the chain & sprockets you would need a 48 tooth rear sprocket. So Duggie's statement about mountain bikes "with extra massive cogs in the back" is correct.There are bafang accessory "bling ring"s available in 32 or 28 tooth. The only other "chain ring"s listed are 40 tooth, 42 tooth, and 44 tooth.
Of course Duggies "1000 w bafang mid drive" motor is likely to be confiscated by UK customs. Write your Parlament representative, UK is interested in converting personal transport to battery power. Not in making the voters walk home from the bus stop pushing their grocery cart.
 
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AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
This fantasy persists all over electricbikereview forum. Mid drives have usually a 46 tooth sprocket or so. They have some internal gearing, but the quoted torque is at the drive chain ring. For a mid drive to get torque multiplication "through the gears in the back", the largest rear sprocket has to be bigger than the front. The stock bafang 1000w chainring is 46 tooth. https://bafangusadirect.com/collect...bafang-1000w-bbshd-mid-drive-ebike-motor-kit# That means to get any torque multiplication from the chain & sprockets you would need a 48 tooth rear sprocket. So Duggie's statement about mountain bikes "with extra massive cogs in the back" is correct.There are bafang accessory "bling ring"s available in 32 or 28 tooth. The only other "chain ring"s listed are 40 tooth, 42 tooth, and 44 tooth.
Of course Duggies "1000 w bafang mid drive" motor is likely to be confiscated by UK customs. Write your Parlament representative, UK is interested in converting personal transport to battery power. Not in making the voters walk home from the bus stop pushing their grocery cart.
Get your face out of the book long enough to put your butt on both types, then get back with me.
 

tomjasz

Well-Known Member
Sorry. Didn't mean to offend. Why do you take issue with the statement? I can understand how some folks want a throttle to help get started. I can understand how some of our fellow posters have had life altering health events, like I have (and have posted about) that raise the need for more riding assistance. What I have a hard time understanding is how someone like the OP can want to power up hills without pedaling at all. Is that biking?
Why does it matter? We have no windows into anyone else’s life. I think many eBike choices made by a number of posters are a mistake but it’s not my place to judge. I do comment on safety and scary battery choices. I was just trolled for building a trike. I just don’t think it’s appropriate. I used to comment on what I consider fad eBikes and sub $1500 eBikes. All I did was alienate someone. Not everyone can buy a $3000 + eBike. I probably over reacted. In my experience those cheap kits and overpowered cheap bikes are the real hazard and will mean more regulations. Bikes like SurRon ARE motor cycles with pedals and throttles. But what harm am I or anyone throttling up a hill at 10-15MPH? What about Hydra class bikes built to ride at motor scooter speeds sans insurance or proven riding skills?

Let me apologize so we can continue enjoying and liking each other’s posts.

Tom
 

retiredNH

Well-Known Member
Region
USA
Why does it matter? We have no windows into anyone else’s life. I think many eBike choices made by a number of posters are a mistake but it’s not my place to judge. I do comment on safety and scary battery choices. I was just trolled for building a trike. I just don’t think it’s appropriate. I used to comment on what I consider fad eBikes and sub $1500 eBikes. All I did was alienate someone. Not everyone can buy a $3000 + eBike. I probably over reacted. In my experience those cheap kits and overpowered cheap bikes are the real hazard and will mean more regulations. Bikes like SurRon ARE motor cycles with pedals and throttles. But what harm am I or anyone throttling up a hill at 10-15MPH? What about Hydra class bikes built to ride at motor scooter speeds sans insurance or proven riding skills?

Let me apologize so we can continue enjoying and liking each other’s posts.

Tom
Understand. My point to the OP was to not neglect a class of relatively inexpensive transportation, scooters etc. that don't pretend to be bicycles and would probably meet the stated needs better. We the public would probably be a bit better protected too by the licensing and insurance requirements that many of these vehicles require. Most of these high powered "bikes" that I see mentioned on these boards are quite heavy, often approaching 100 lbs, so they can pose even more of a threat than my 56 lb ebike, especially if someone takes too much advantage of all that power. It's an issue I don't see discussed very much among those seeking ever more power and speed.
 

duggie

Member
Region
United Kingdom
Indianajo.......All that debate very helpful to me. I'm with indianajo, that the rear cog needs to be big and the drive cog to be small. Like I always thought: block and tackle. That is what i wanted confirming. Thanks.

RetiredNH........I don't want to pedal up hills because it knackers me and I am an easy rider. That said, I only want to travel, mainly, a mile, off road, and no faster than 5mph. I'm not into cycling with all the effort. I just want to get to and from my allotment with no effort. Why should that be so bad to ask? People seem to have a default position about someone who says they don't like pedalling, that they are a speed merchant pulling wheelies on pavements. I'm just an old lazy bloke with a heart condition, haha.

I'll get the 1000w banfang mid drive kit with the 42, see how that works, then look to a bigger back cog if necessary. Thanks you all very much folks. You have all been soooo helpful. I have learnt a lot in just a few weeks thanks to you.
 

tomjasz

Well-Known Member
Well Joe has it not quite right. He has zero experience with BAFANG mid drives. A 42T chainring with a 14T-32T freewheel/cassette is a veritable mountain goat. To go smaller on the front and still maintain a chain line only a Lekkie 40T kit, about $150USD will maintain a decent chainline. A 36T front will have no offset. I sold and supported 100s of BBSHD kits and personally had 3 different frames with 3 BBSHD motors.

What make model and year of bike are you converting?
The BBSHD is very popular with pedicabs. Again it’s a beast of burden.
All the best!

Tom
 

duggie

Member
Region
United Kingdom
tom.........that is good info for me. It is just the bike I showed at the beginning of this thread
1656796644699.png
about twenty years old, an Apollo. It will be just fine for my needs, if I can get a bigger cog on the rear if I need it. Me and GF tour a bit so need the small folding. I'm over the Moon about what you have said in your posts for me. I really think I'm getting it now. I reckon I can now sort that damn bloody hill which has been the drag for me and my allotment. doug
 

duggie

Member
Region
United Kingdom
It's just gearing. Simple as that. Gearing, and don't they know it, an extra couple of grand for a couple of unusually sized cogs. A mid drive is a must, then just an 'oversized' cog on the back wheel and an undersized cog on the crank. Pretty much as simple as that. Eeeee. Got there, got through the barrier. I'm a, was, a beginner. thanks folks. I get it now. Thanks very much. Simple as that, essentially