What's the Scorecard on Mid-drive?

[PowerMe]

Noise is comparative as well as objective. One may not notice a certain level of noise until or unless they have an opportunity to hear something different in the same type of object (like geared hub vs mid-drive). Then again, it's also subjective.

 

[Toynut]

" One man's noise is another man's music", or so the saying goes.
BTW,
How many of you remember putting playing cards in your bicycle spokes as a kid to get that "motorcycle" sound?

 

[Reddy Kilowatt]

I'm really old, so I reckon I will never forgive my Mom for throwing away all those cool baseball cards. Heck, I could retire on my Mickey Mantle rookie card, no?
But yeah, the cards did sound nice in the spokes; so much better than the time my friend was giving me a ride barefoot and my toes went in the spokes. That (me) made a way different sound, though if you took away the swear words, I probably didn't say anything.
Allen

 

[Toynut]

Same thing happened to me when I was a little kid(about 5). Older boy gave me a ride on the handlebars on an English 3 speed. As he pumped hard on the peddles the bike swayed side to side. I got my toes (barefoot in flip flops) into the spokes behind the front fork locking up the front wheel, and over the bars we both went, head first onto the sidewalk.
Till this day I don't wear open toed sandals.

 

[Reddy Kilowatt]

Yeah Toynut:
That's the same way I got hurt.
Speaking of handlebars, an old guy—who was a commercial fisherman in the early mornings then worked in my Dad's boatyard by day—used to show off by sitting on the handlebars and riding my bike backwards. He was about 60 at the time!
That was a pretty neat trick which used to impress the hell out of me and my buddies when I was a young boy. Too bad "Babe" didn't live to see eBikes; no need to pedal.
Good thing we didn't have eBikes either, cuz' one of our favorite stunts was to tie our bikes with a rope, then ride them off the town dock, swim back, and haul the bike back out of the harbor by the rope. This was salt water of course. Aaah, sweet bird of youth.
Allen

 

[Toynut]

Reddy,
This looks like a new take on an old idea:

http://www.turbospoke.com

 

[Ace]

In the Volton area I posted my initial review (includes mid-drive vs. rear geared info).

http://electricbikereview.com/community/threads/volton-mid-drive-500w-48v-owner-review.1621/

 

[tinasdude]

Another vote for mid drive. Some of us are older. Some travel and some may be travelling. Don't want my e-bike limited by the landscape. Don't want to be limited to where I travel because of an E-bike's deficits. 750w BBSO2 FAT BIKE. Go anywhere you want. Lot of beautiful places all over the USA that have narly roads

 

[J.R.]

Another vote for mid drive. Some of us are older. Some travel and some may be travelling. Don't want my e-bike limited by the landscape. Don't want to be limited to where I travel because of an E-bike's deficits. 750w BBSO2 FAT BIKE. Go anywhere you want. Lot of beautiful places all over the USA that have narly roads

Gobs of power there!!! Hope you can give us a full review of your new bike when you have time. Enjoy!

 

[tinasdude]

Mine is going to be one of the last seven delivered, but I will definitely post it on the Juggernaut thread when I get it.

 

[vincent713]

Mid-drives can easily exceed 30mph. The Bosch motor distributors have wisely chosen to obey United States regulations, instead of wandering into the gray area of the speed pedelecs. Therefore, most are limited artificially to 20 miles per hour at the current time.

I'm trying to understand more about mid drive and this might be a dumb question. If MD runs and rely on the chain and you switch it to high gear, the speed will be faster correct? Wouldn't this not be in compliance to the 20mph speed limit in the US?

 

[Reddy Kilowatt]

This is handled by the software in the controller. It knows how fast the bike is traveling by virtue of the speed sensor. In my bike's case, there's a magnetic sensor on the left chainstay and a corresponding magnet on one of the rear spokes. So no matter what gear you choose, the eBike's top speed is electronically-limited by the controller.
Allen

 

[vincent713]

This is handled by the software in the controller. It knows how fast the bike is traveling by virtue of the speed sensor. In my bike's case, there's a magnetic sensor on the rear chainstay and a corresponding magnet on one of the rear spokes. So no matter what gear you choose, the eBike's top speed is electronically-limited by the controller.
Allen

Ahh this makes a lot of sense and thank you for the clarification. Now that I have a better understanding, I would have to agree with the folks that say MD is complicated, over priced and over hyped but that's just merely base on speculation. I have ridden a MD once only for a few minutes and it felt pretty much the same as a hub motor except when I tried switching gears while using the PAS. It made a lot of clunking noise and thought I had broken the chain. That wasn't a pleasant experience and found it to be a down fall.

 

[NoDTMF]

Just a small clarification, the bike can go as fast as you can peddle, the assist just cuts off...in my case at 16 mph.

Also I do not understand the "MD is complicated" comments from @vincent713. My bike shifts smoothly just like any non-ebike with a rear derailleur. I assume the quality of the components should be to blame, not the MD. BTW I got a flat today on the rear wheel, sure was easy to fix (but inconvenient as I was on the way to work).

 

[vincent713]

People seem to think rear hub motors are harder to fix flat but from my experience, all I had to do was unplug the motor wire and the rest becomes just like any other bicycle. Unscrew both nuts, loosen the chain and pull the tire off. Yes the hub motor wheel is a bit heavier but put some elbow grease into it and it comes right off!

 

[NoDTMF]

That's good feedback...So, it must come down to the quality of the design. There are posts floating around about how difficult some people found fixing flats on rear hubs.

 

[mountain biker]

hey guys thanks for allowing such a great forum. new here.... in general the mid drive may be limited in gear range because alot of the popular mid drives like bafang and bewo seem to say you must have only one crankset gear...leaving only the rear cassete to give you the range. and they seem to encourage the use of six speed sprockets claiming they are more reliable to hold up the torque. you can buy a 14 to 34 casssete six speed from shimano for like 15 bucks... this seems to be the greatest range that can be found commercially in a cassete...the other way is to go igh shimano alfine 8 or nuvinci....etc...... but your looking at 250 bucks just for the hub not counting lacing and another fifty bucks for shifters etc.....i got quoted out from a bike shop 300 igh,shifter,shimano alfine8 and 200 bucks for lacing and labor and spokes. also if your looking at first gear having a reduction. your shimano alfine 8 has a .56 reduction and a high of 1.6 overdrive roughly....they claim you need 1.8 to 2.1 from the crank shaft to cog gear in rear...well if you do the math first gear really doesn't have much reduction or none at all. and overdrive would be 2 times 1.6...so like 3 times your crank input. so five hundred bucks of igh gets you 300 percent range and 20 bucks gets you 230 percent range........seriouslly..crazy right.....and you thought batteries were expensive try an alfine 11 or a roholff.......
something kinda of interesting i noticed that 7 speed free wheels have an 11 to 34 spread.......i believe the chain tensile strength is comparable to six...so maybe...thats a 300 percent (little more) range for like 20 bucks. start off with a 30t crankset give yourself 12 percent reduction(sorry...hopemath is right) and then do 30 to 11 rear sprocket overdrive in gear seven at 90 rpm roughly 270 to 280 crazy right?

 

[Bike_On]

I use to run an 11-32 and 11-34 9 speed freewheel cassette on an Optibike 800W mid drive. That had a lot of torque and would wear the chain and cogs. A good quality chain and cassette will be fine. For higher torque MD's, plan on changing the chain yearly, and cassette 1-2 years depending on # of miles. The chain will stretch and the lower cogs wear and the chain will start to slip. You will get a solid year, maybe 2.

 

[harryS]

I decided my next e-bike would have a bafang BBS02 mid-drive, and the donor would be my old Diamondback mountain bike, but I recently picked up a cheap fat tire bike. A fat tire bike is an good mid drive candidate, because I don't have to mess around with the rims and tires, but the only mid drive that fits the fatbike BB is the Bafang HD, which has more power than I want, although the most recent user reviews say it doesn't have the power that the top posters on endless-sphere crave.

I've ordered two small geared hub motors instead to attempt a 2WD fatbike for slow speed winter riding in snow . One comes with a 190mm dropout to fit the rear and is supposed to have a rim. The other is a bare motor for the front so I ordered a rim and will learn how to lace it. Total cost so far is more than what a BBS02 would have cost me, but less than the HD which I didn't want anyway.

So my BBS02 build will be deferred. Maybe next summer. The BBS02 will be more than fast enough for me, and I know how to shift and keep a motor happy. That's one thing about the US market. We're a nation that drives cars with big engines and automatic transmissions. and most people just don't understand gears. If you're willing to help the motor out with pedalling, any bike can climb most hills.