I think I know the answer to this but w/electric bikes 1+1 doesn't always =2. With mid drive using the gearing of the bike does it let the battery work less going up hills, say in 2nd gear vs 12th? Talking a 21sp bike here. Are only 1 sprockets used on mid drives up front? Can 3 sprockets be used up front? Also does using the gearing extend the range of the battery if gearing is used like driving a car? I'm talking about using a quality mid drive not junk, good brand name. I'm aware of the wear mid drives put on the drive train vs a hub motor. It seems if battery life/range/power are extended by using a mid drive it compensates for the premature wear. What say you?
Mid drive vs hub?
- Thread starter 2wheeler
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indianajo
Well-Known Member
This is an odd place to put this. Juiced bikes are all hub drive aren't they?
Most mid drives allow only one sprocket to be used up front. Using a higher gear up a hill than necessary draws more current and shortens range imho. Higher gear means smaller rear sprocket. Electric motors are more efficient at higher rotational speeds. One brand of mid-drive allows 2 sprockets up front but I forget which one. I need 36:32 range to get up 15% grade without electricity, and I need 52:11 range to help the motor by pedaling over 13 mph.
Be aware that mid-drives besides the yamaha require the rider to use electricity 100% of the time, or drag the motor with the human energy. I ride my DD hub drive 95% of the time pedaling myself, only using the electricity for strong headwinds, trips over 30 miles, or making 8 second green lights crossing 6 lane streets. That's over 2000 miles a year pedaling unpowered. The cardiologist after $5000 in tests said "there is nothing wrong with your heart" and the Nurse Practitioner said this spring my choresterol was "right where it needs to be". I'm age 68. Geared hub drives drag even less than the DD drive.
Most mid drives allow only one sprocket to be used up front. Using a higher gear up a hill than necessary draws more current and shortens range imho. Higher gear means smaller rear sprocket. Electric motors are more efficient at higher rotational speeds. One brand of mid-drive allows 2 sprockets up front but I forget which one. I need 36:32 range to get up 15% grade without electricity, and I need 52:11 range to help the motor by pedaling over 13 mph.
Be aware that mid-drives besides the yamaha require the rider to use electricity 100% of the time, or drag the motor with the human energy. I ride my DD hub drive 95% of the time pedaling myself, only using the electricity for strong headwinds, trips over 30 miles, or making 8 second green lights crossing 6 lane streets. That's over 2000 miles a year pedaling unpowered. The cardiologist after $5000 in tests said "there is nothing wrong with your heart" and the Nurse Practitioner said this spring my choresterol was "right where it needs to be". I'm age 68. Geared hub drives drag even less than the DD drive.
LimboJim
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- USA
I've ridden Yamaha and Brose powered bikes that were equipped with two chainrings, and Bosch has been the only mid-drive that I've experienced noticeable drag from. Brose and Shimano motors seem to decouple completely when they're turned off, with no drag that I could feel.
Alaskan
Well-Known Member
I ride a Bosch driven bike. I put 6200 miles on Bosch bikes last year. I changed chain twice. Both times the "stretch has reach .5% - less than the 75% recommended as a change point. Everything I have read about hub driven ebikes, contributions from both fans of hub motors and otherwise, indicates that your supposition about more range per electron, especially in hilly country. This conclusion is supported by just about all posts that I have read here. Hub motors have clear advantages as well. Good attention to chain cleanliness and proper lubrication are good preventive on the drive train wear side (true on every bicycle with a chain)
harryS
Well-Known Member
Well, the simple answer is that mid drives climb hills with smaller motors than hub drives. You want a mid drive if there's a lot of hills.
KMC mountain bike chains are under $10, while their ebike chains for 7 speeds are only $15. I bought a new chain for my bafang mid drive kit but haven't used it yet, However, I don't do 6200 miles like Mr. Alaskan. Hats off to you!
KMC mountain bike chains are under $10, while their ebike chains for 7 speeds are only $15. I bought a new chain for my bafang mid drive kit but haven't used it yet, However, I don't do 6200 miles like Mr. Alaskan. Hats off to you!
Ravi Kempaiah
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- Canada
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- Halifax
Unfortunately, it doesn't.
You have about 7000 miles on your Vado 6.0 and have had 3 motor replacements and several cassette and chain replacements.
@Chris Hammond has probably just as many miles on his Juiced CCS, averages faster than you at ~25-27mph for his 60+ miles round trip commute. Take a look at his thread.
https://electricbikereview.com/foru...cs-also-my-first-5-months-of-owning-it.23853/
I don't think he has replaced any motor or wheel or multiple cassettes (may be brake pads or chain) but nothing substantial.
A Juiced CCX or any qualitu hub drive will maintain higher avg speed, provide excellent range and still minimize drivetrain wear. The range extension arising from a mid-drive happens because these drives run at 350W (36V, 15-18A controllers) and do not exert themselves for high speed cruising. They are designed for EU countries where the commute distances are shorter and avg speed is much less. When you try to use such a system for 40+ miles day, you will quickly realize the downsides.
if you want to maintain 20+ mph avg speed, mid-drives are not the best. They stress the drivetrain severely at those speeds and distances. To minimize such wear/tear, you would have to use something like Rohloff but that adds a lot of cost. Even then, just by the laws of physics, it's not built for that kind of power output. You could build a mid-drive that will outperform any hub drive but majority of the mainstream mid-drives (250 to 350W) are built for EU centric commutes or MTB riding. Mid-drives really shine for mountain biking and in extremely hilly terrain.
There is another rider who does a lot of miles @hurricane56 . He has a Bosch speed pedelec and a custom HyperFat. A 48V,20A controller on hub drives will certainly be zippy and gets you to destination faster.
Another rider who has experience on hub and mid-drives is @linklemming who has Brose S-pedelecs and hub drives.
So, in summary, you asked does the mid-drive gearing efficiency compensate for the drive train wear compared to a hub drive?
I recommend you rent a Juiced CCX for 3 weeks and commute on it. You will have a clear answer.
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ebikemom
Well-Known Member
Great reply, @Ravi Kempaiah !
Mid-drives are popular in Japan--short distances, lots of hills. There are Japanese hub drive bikes, also, though.
I commute, and my hub drive is great for me (besides which, it's a lot of fun feeling the "juice" kick in! On that note, "Juiced" is a great name for a hub-drive ebike!!)
Mid-drives are popular in Japan--short distances, lots of hills. There are Japanese hub drive bikes, also, though.
I commute, and my hub drive is great for me (besides which, it's a lot of fun feeling the "juice" kick in! On that note, "Juiced" is a great name for a hub-drive ebike!!)
Is this really true? I'm new to ebiking, and have spoken to a bunch of bike shop employees and a couple of ebike riders. They've all told me the majority of the additional drivetrain wear comes from hard use. I've been told over and over that if I baby the drivetrain....ease off pedaling while shifting, don't grind gears, and keep everything cleaned and lubed, my mid drive should have a life long enough to make it a wash with a hub drive. I've never heard that maintaining a high average speed (19-20mph) would dramatically shorten the life of my drivechain!???
Are you saying the motor will die out? I have long stretches of straightaway that I've enjoyed blasting thru at 19mph...passing analog roadies on my e-mtb. Am i damaging my ride?
Ravi Kempaiah
Well-Known Member
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- Canada
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- Halifax
I got confused with 2 different posters here.
@2wheels and @2wheeler
@2wheels has had multiple motor replacements and drivetrain component replacement. Read here: https://electricbikereview.com/foru...p-approximately-8500-miles.25229/#post-178034
Another rider who has had multiple motor replacements is Adam and he writes about it here: https://www.strava.com/clubs/108312/posts/4887804
Both @2wheels and Adam alter are powerful riders who commute long distances AND at high speeds. They are almost pushing these drives to the limit.
When you run these mid-drives at higher assist levels, you are really stressing the gear cassette quite a bit. If you do commute 40+ miles a day like those riders did, you will realize what I am talking about here.
If you are a recreational rider, you may not run into these issues.
Chris Hammond
Well-Known Member
So to clarify my wear and tear issues, replaced both front and rear brake pads at ~3900 miles, replaced rear tire at ~3500 miles, replaced chain at ~5000 miles. Motor remains strong and trouble free. I inspected chainring and cassette when doing the chain, expecting to need to replace, both looked great and no issues with new chain.
Ravi is absolutely correct about maintenance related to high speed commuting. Mid-drives are great, but optimized for lower speeds, and at lower speeds provide many advantages that hub drives just can't compete with. At high speeds the pendulum swings back in favor of hub drives. Geared hubs give some level of compromise between the DD hubs and mid-drives, however, motor winding of hubs will dictate its performance at various speeds and maximum speed for a given voltage.
I notice you have (or had) a Juggernaut with the Bafang Ultra 1000 and I've been considering a similar one -vs- a rear hub bike like a Juiced RipCurrent S.
I'm considering a generic version of the Jugg (though it has some lesser-spec'd parts - same motor and frame) and had a few questions if you don't mind? I think your responses will be of interest to thread subs also.
First let me state my situation and anticipated riding profile:
A) I'm not a serious rider. I don't do tracks or technical rides. I have a knee that isn't great (I need a throttle). I would use primarily on roads or grassy / dirt trails, rarely any hills involved. I would like to go fast on occasion, I would like to shift gears on occasion.
B) I've ridden a Yamaha mid-drive and loved the fact that I felt like superman, but felt like I was doing the pedaling (even though the bike was doing most of it). Knee was OK with it, but I want / need a throttle.
C) I've ridden a few other hub-drive bikes (one had a cadence + torque sensor, other cadence only) - I felt disconnected from the pedaling. They had ample power to be sure, but as soon as I started pedaling the things just take off. I'm sure I could probably get used to it.
Questions:
1) How much shifting is needed for casual / slower riding? Say if I want to cruise with my wife at around 12mph on level ground, could I leave it in, say, 3rd gear and use throttle from a dead stop, and never have to really shift out of 3rd? I don't want to exert much pressure on my knee, and with a rear hub I can use the throttle to start off (no matter the gear I'm in, and don't have to remember to down shift before stopping) and then start pedaling once the bike is rolling. I do realize the max efficiency will always be achieved by using the gears, and that those nice high speeds will require shifting (no problem, but I don't want to constantly have to do that if I'm casually riding with my wife).
2) When shifting under power (PAS or throttle) does the motor cut / reduce power during the shift (I guess controller would be doing this actually)?
3) Does the controller / display offer good control over max speeds, amp. draws, slow start adj. etc? I wouldn't want this thing to do a wheelie on my way to the mailbox... I'm a big fan of adjustments and options.
4) I notice your seatpost frame member is a round tube all the way to where it is welded to the motor top-plate. I see some photos of other Juggs that have a widened seat post frame tube where it meets the motor plate (which looks to me like it would be stronger) - I wonder if this was a weak area at some point and the design was changed?
Thanks for your insight!
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Reason I posted hub vs mid here is that a lot of you guys know a lot and have experience and aren't afraid to share it. I sold my CCX in order to be able to afford a 250 m/c dual sport. I wouldn't hesitate to buy another CCX at all, beautiful bike and it performs well. Lots of features for the money, none other can compete at the price point. Anyways I've been just looking at other ebikes and at the mid drives and was just curious about them. I've learned as a recreational user only one doesn't need a lot of the high end features the expensive bikes offer. My next ebike some day might include a mid drive and a more powerful battery. Say 30ah or 2 15ah batts for range. I'm just rambling but enjoy this subject a lot.
TForan
Well-Known Member
1) Shifting around town and on smaller hills is nearly optional with the Ultra.
2) Yes, it has shift sensor, that works well.
3) No problem
4) I don't think it's anything to worry about.
How did the torque sensor feel to you on the CCX -vs- your mid drive bike in terms of modulating the power delivery in tune with your peddling?
I'm guessing there is a pretty major difference in pedal feel between the two?
Thanks for your input - much appreciated.
joshuaho96
Member
Motor will not break from extended high speed use, no idea who came up with that considering that riding at speed gives more airflow for cooling. Most mid-drives integrate the controller into the motor down low, with proper thermal coupling to the enclosure it will cool.
Regarding drivetrain wear at high speeds, I think people are confused here. The primary cause of accelerated drivetrain wear is excessive torque loads on the drivetrain. The reason why you need to be careful with shifts is because that is when torque loading on the cassette and chain can be enormous. The reason why Ravi is claiming that high speeds wear out drivetrains is mostly because of how people get to those high speeds in a mid-drive, which is they slam into the high gears when shifting without a power cut + gentle power ramp to get it into gear, and they get into the high gears at relatively low speeds which greatly increases torque loading. Combine that with sub-optimal chain line and higher wear is inevitable.
If you are gentle when shifting into the last ~3-4 gears and only do so when the bike is at high speed you will greatly reduce wear on those cogs. Mid-drive is supposed to require shifting like a manual transmission, you want to keep the motor RPMs high and use your gears to accomplish that. Unlike a gasoline engine where high RPM reduces your efficiency, high RPM in electric motors increases efficiency. I only avoid shifting into my bottom-most granny gear to avoid pulling wheelies. If I'm not on the road with cars I also stay out of my high gears to begin with and reduce my speed.
ebikemom
Well-Known Member
Yup, and if you do ever encounter an incline/hill where you need to stop, a throttle is awesome for starting on hills. approaching a hill, sometimes I change gears, sometimes I up the PAS and sometimes I do both.
You mention no problem for #3 - Do you have the programming cable and have you manipulated the motor programming or are you just talking about the typical display properties (max speed, tire size etc..) because amp draw, slow start settings, assist %, torque % and the other very specific parameters are apparently all in the USB / PC interface SW and unavailable from the bike display. I was unaware of this.
joshuaho96
Member
All of those parameters are easily manipulated with a USB cable that converts to the Higo for the display, lots of programming cables for sale out there. The software is also readily available, just use a laptop to program your controller.
Most displays will not allow you to do big changes, if the controller accepts requests from the display you can use it to set speed limits and similar small changes but nothing crazy.
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