Electric Bikes - Two sets of gear in the rear?

Assuming there is room, is it physically possible to install a hub gear and cassette of gear on the rear wheel?

My reason for asking...I have been scourging the web and this forum to do research about converting a bike to an ebike. I have come to the conclusion that, because I cannot be certain about the strength or materials used in the forks of the inexpensive bikes available to me that a front mounted motor is not a good idea if higher torque is needed. I have also come to the conclusion that weight distribution on an ebike or any bike is important, if not crucial, especially as you pass 20 mph and are in a situation with less than ideal road conditions. A lower center of gravity also seems to be crucial.

The option I am looking at now is installing a motor somewhere in the middle of the bike connecting to a hub gear and still having a typical cassette in the rear end attached to the pedals. I want the hub gear because it is easier to change gears in a stop and start situation, i.e. inner city traffic, which is about 70% of the use of the bike. The cassette and derailler will be used outside the city on longer rides. Is this possible? I am hoping that a scenario like this will eliminate the need for a freewheel and, in general, will reduce the complexity of the whole system. I am looking at converting a mountain bike that has a 5 or 6 gear cassette in the rear. I don't think space will be an issue because the hub gear is about the same width as a normal hub.

I know this is a bit of a complex question...I will appreciate any insight you can provide.

Sram dual drive? (http://www.universalcycles.com/shopping/product_details.php?id=10687)

Search around for info on Randy Draper's bike as he uses what you're describing. It's too bad his personality problems got himself banned here... he was occasionaly a good source of technical info.

Behold Sheldon Brown's 63-speed Frankenbike (my term, not his). It has a 3-speed rear hub with 7 sprockets, and a triple chainring.

http://sheldonbrown.org/otb.html

--J

Search around for info on Randy Draper's bike as he uses what you're describing. It's too bad his personality problems got himself banned here... he was occasionaly a good source of technical info.

Draper got banned here too? LOL... Never a good source of technical info that I've seen. Too much BS, sand-bagging and guess-timating for me to find ANY of his perceived knowledge useful.

So he built a CRUDE electric motorcycle and somehow weasel'd himself into a bicycle race with it! 'Glad to see the mods figured out his problem and put him off this site.

Thanks! But I am not trying to compound the gears, but to separate them. I am hoping that the chain on the right side will go from the crank to the cassette. The chain on the left side will go from the motor to the hub gear.

The chain on the left side will go from the motor to the hub gear.

Wouldn't that be backwards from how it's intended to rotate? In other words, it would only work in reverse, yes?

Recumbent bkes have tons of gearing goodies, perhaps look into a supplier who deals with those parts? Not sure you will find what you're looking for but that would be where I would dig for motor gearing options.

[QUOTE=BroadwayJoe;5442998]Wouldn't that be backwards from how it's intended to rotate? In other words, it would only work in reverse, yes?

That is a good point. That is why I want the motor on the left side of the bike. I can change the direction of the motor to correspond to the need of the gear. One of my problems is that I have never seen one of these gear hubs so I don't know how they work. What are they anchored to? What do they push against? I should probably buy one and a cassette and see if I can play around with them to get it work. I am hesitant because I am not sure if it is even possible, let alone probable. Can anyone comment on this aspect? Is it possible? probable? The idea seems very simple.

Another thought I had...is to mount a transmission from a 100 cc motorcycle to the frame, make the motor drive the transmission and the transmission directly drive the wheel. I have never seen a transmission from a small m'cycle though so I don't know the weight or the shape.

Hub gear - basically an inner shaft connected to outer housing through gears. Depending on the gear selected - for every full rotation of the inside shaft the outer shaft may only rotate 1/4 or 1/2 or 1:1 turns. Trouble is, they only hook-up in one direction and that direction is for RH chain drive. Flip it over to the LH and it will work but only if you want your bike to drive backwards.

Yes, you can mount it remotely and work it as a transmission - will need countershafts, mounting brackets, hardware, more gears/chains, etc. Small transmissions are NOT limited to bicycles - industrial automation has many chain drive components as well as robot builders, etc. Some folks have mentioned electric drill transmissions, CVT's and all kinda crazy means to gear chainring/motors into a bike.

Small motorcycle transmission would be unlikely to work easily - they're usually built integral to the engine crankshaft cases so would need lotsa cutting and rework to put the transmission section into useful footprint for a bicycle.

Set on gear drive? Go for it - but it's very hard to do CLEANLY and with minimal weight and complexity. That's why hub motors offer a much simpler method and are the most common kits for converting practically ANY bicycle to electric.

The best geared drive system I've used with an internal rear hub or cassette gear is the Panasonic unit offered only as OEM - motor drives the front chainwheel. In Japan, they're quite plentiful on both Panasonic and National brand bicycles. I've found 'em on Japanese websites but I don't know the language or if it's even possible to buy one from outside the country?

I suggest - instead of shooting for the uncharted stars with building your 1st eBike, just get a decent one going with commonly available components. Put most money into batteries, BLDC motor, brakes and tires and I guarantee you will have a decent ride while learning more about eBikes than you ever dreamed possible!

Nothing wrong with pushing design envelopes but until you've lived in the seat of an eBike you won't know nearly enough to make much sense out of ALL the possiblities.

Good advice...maybe that will give me time to learn how to weld and buy a tig outfit...and make my own from scratch :)

Draper got banned here too? LOL... Never a good source of technical info that I've seen. Too much BS, sand-bagging and guess-timating for me to find ANY of his perceived knowledge useful.

So he built a CRUDE electric motorcycle and somehow weasel'd himself into a bicycle race with it! 'Glad to see the mods figured out his problem and put him off this site.As crude as YOU think it is No one has matched its performance or efficiency with over 25,000 miles and NO failures. Nor has any other ebike made a 10,005 ft elevation climb in 36 miles up hill with the same set up that will go 45 mph on the flats. So does it piss you off for not being able to build such a ebike yourself?

Search around for info on Randy Draper's bike as he uses what you're describing. It's too bad his personality problems got himself banned here... he was occasionaly a good source of technical info. And I suppose YOUR lies had nothing to do with it.

As crude as YOU think it is No one has matched its performance or efficiency with over 25,000 miles and NO failures. Nor has any other ebike made a 10,005 ft elevation climb in 36 miles up hill with the same set up that will go 45 mph on the flats. So does it piss you off for not being able to build such a ebike yourself?

OMG - it's alive and with vengence! LOL, what HUGE claims and boasts you make. 25k miles - why not tell how many tires it took to go that distance? That way, REAL bike riders would know if you're padding your amazing specs, again. Trouble is, you don't even roughly know how many tires it would require to go 25k miles because you've never done it...

I see nothing about you, so-called designs or your attention starved life for me to be PO'd about - but why are you so angry and bitter all the time? Show us one thread where you've actually counseled and/or advised and didn't gloat about your amazing FEAT (loophole MOTORCYCLE into a bicycle race) and how anything except your way is crap, and everybody else is so stoopid? Huh, got one someplace?

Personally, I don't care - I'm no better than you for replying to this drivel 'so outta here...

Good advice...maybe that will give me time to learn how to weld and buy a tig outfit...and make my own from scratch :)

Hey man - welding's a great skill to have in your bag! Don't shelve your ideas or plans but just suggesting to get something simple working on the road so you have a genuine reference for what's what, dig?

Batteries are the main thing and whatever you develop in that area will work on just about anything you may build in the future. Plus you'll know from experience how many gears you may actually need and how much weight/complexity you can live with? All the good stuff to know that only comes from doing.

rubber down!

Hey man - welding's a great skill to have in your bag! Don't shelve your ideas or plans but just suggesting to get something simple working on the road so you have a genuine reference for what's what, dig?

Batteries are the main thing and whatever you develop in that area will work on just about anything you may build in the future. Plus you'll know from experience how many gears you may actually need and how much weight/complexity you can live with? All the good stuff to know that only comes from doing.

rubber down! So DO IT with out lithiums to climb a 10,oo5 ft high volcano with a 5 lb motor in 3 hours on a $80. Huffy that is still in operation after 25,000 miles on it with how ever many tires and batteries you like. LOL

So DO IT with out lithiums to climb a 10,oo5 ft high volcano with a 5 lb motor in 3 hours on a $80. Huffy that is still in operation after 25,000 miles on it with how ever many tires and batteries you like. LOL

Go away angry little man, - if I want an arguement and general unpleasantness I'll go next door to the neighbours and complain about their dog (sigh).

pengyou, - I'd suggest looking around for some junker bikes to tear down for parts rather than going and buying anything new. There's nothing like being able to handle bike parts and tinker with them when it comes to developing ideas. Personally I would quite like to try a front wheel drive electric bike using a hub gear mounted in a front fork, - which of course leaves the normal bicycle rear wheel and chain drive to carry on as usual.

So DO IT with out lithiums to climb a 10,oo5 ft high volcano with a 5 lb motor in 3 hours on a $80. Huffy that is still in operation after 25,000 miles on it with how ever many tires and batteries you like. LOL

Show us one thread where you've actually counseled and/or advised and didn't gloat about your amazing FEAT (loophole MOTORCYCLE into a bicycle race) and how anything except your way is crap, and everybody else is so stoopid? Huh, got one someplace?

Show us one thread where you've actually counseled and/or advised and didn't gloat about your amazing FEAT (loophole MOTORCYCLE into a bicycle race) and how anything except your way is crap, and everybody else is so stoopid? Huh, got one someplace?I explained how a set up with this frame and a 5 lb motor could be used for any rider and any hill and still go 45 mph without any change if ever needed.Also a 35 lb bike including batteries and motor to go 30 miles at 20 mph without the need to pedal.

Sorry, I find 35lbs hard to believe. A junker full suspension frame like a dual tube huffy will weigh 30+lbs on its own when all together. You'd be over 35 just adding your motor on.

My fuji 2 carries many (many) times the price in quality and components, and weighs considerably less than any of these cheap dual-tube cows will. Even if you used a 5lb motor, stripped the unnecessary components, and used nothing but lithium you'd never have the ability to meet 35lbs and squeeze anything other than a single pack onto the bike.

Perhaps on a lightweight racing bike you could get that kind of range, some of them go down into the 17lb range. However, i'm just going to call your BS on the huffy, and your claim.

Sorry, I find 35lbs hard to believe. A junker full suspension frame like a dual tube huffy will weigh 30+lbs on its own when all together. You'd be over 35 just adding your motor on.

My fuji 2 carries many (many) times the price in quality and components, and weighs considerably less than any of these cheap dual-tube cows will. Even if you used a 5lb motor, stripped the unnecessary components, and used nothing but lithium you'd never have the ability to meet 35lbs and squeeze anything other than a single pack onto the bike.

Perhaps on a lightweight racing bike you could get that kind of range, some of them go down into the 17lb range. However, i'm just going to call your BS on the huffy, and your claim. Huffy ?

So DO IT with out lithiums to climb a 10,oo5 ft high volcano with a 5 lb motor in 3 hours on a $80. Huffy that is still in operation after 25,000 miles on it with how ever many tires and batteries you like. LOL

Huffy?

That huffy. The one you're talking about, right?

Ah, now I see that you're just talking about making a 35lb ebike, not claiming that one to be 35lb. Still, I doubt you'd get those numbers on an ebike without putting together some *very* lightweight and purpose built components. By then you're hardly talking about using an $80 bike frame.

I think you'd be hard pressed to meet 35lbs using a full-suspension frame and keep a decent power capacity, seems like the best route for achieving a total low-weight unit would be to use as much passive suspension as possible and skip adding any additional components altogether.

Personally, my setup weighs in at 47lbs, has about that 30 mile range, probably plus 4-5 miles, but none of the speed, maxes out at around 41kph. There is one crucial difference here though, thats the hub motor opposed to chain drive. You could probably shave 8-9lbs there, but i'm a winter rider, and I don't know of any frame mount motors that will take constant weather exposure without looking at serious damage from salt exposure: Riding conditions here are drastically different from Hawaii, i'd imagine. The Crystalyte on the other hand, will take that sort of punishment if you properly seal up the casing.

That huffy. The one you're talking about, right?

Ah, now I see that you're just talking about making a 35lb ebike, not claiming that one to be 35lb. Still, I doubt you'd get those numbers on an ebike without putting together some *very* lightweight and purpose built components. By then you're hardly talking about using an $80 bike frame.

I think you'd be hard pressed to meet 35lbs using a full-suspension frame and keep a decent power capacity, seems like the best route for achieving a total low-weight unit would be to use as much passive suspension as possible and skip adding any additional components altogether.

Personally, my setup weighs in at 47lbs, has about that 30 mile range, probably plus 4-5 miles, but none of the speed, maxes out at around 41kph. There is one crucial difference here though, thats the hub motor opposed to chain drive. You could probably shave 8-9lbs there, but i'm a winter rider, and I don't know of any frame mount motors that will take constant weather exposure without looking at serious damage from salt exposure: Riding conditions here are drastically different from Hawaii, i'd imagine. The Crystalyte on the other hand, will take that sort of punishment if you properly seal up the casing.This or simular frames and swing arm made of aluminum would weigh less than 12 lbs the complete full suspension bike at 25 lbs without any unneeded derailers. a 5 lb , 1500 watt motor plus a 7 lb 12 ah lithium battery of 7 lbs= a 37 lb ebike good for 30 mile range WITHOUT any pedaling.
I doubt any heavy hub motor can be sealed or take the pounding from off road abuse. For near flat land use and on smooth roads i'm sure some people may choose from heavy low power kits available. They don't really have much of a choice.Yet.

This or simular frames and swing arm made of aluminum would weigh less than 12 lbs the complete full suspension bike at 25 lbs without any unneeded derailers. a 5 lb , 1500 watt motor plus a 7 lb 12 ah lithium battery of 7 lbs= a 37 lb ebike good for 30 mile range WITHOUT any pedaling.
I doubt any heavy hub motor can be sealed or take the pounding from off road abuse. For near flat land use and on smooth roads i'm sure some people may choose from heavy low power kits available. They don't really have much of a choice.Yet.

From personal experience i'll let you know that a Crystalyte 4 series can both be sealed, and withstand considerable punishment. The 408 has taken a Canadian winter and several trips to some of the more technical trail the rockies have to offer without any maintenance or damage. A BionX is superior still, it comes in around the same weight as the frame motors once you add in the additional freewheel, is made of aluminum, and has the same strength as any other hub will offer. One advantage that rear suspension gets you in this case is that the dynamic load on the motor is considerably lessened during impact with the ground after getting some vertical motion :)

I suppose you *could* build a bike that way and have it come in at 37lbs. But you're going to send your customers off to do offroading without mudguards or derailleurs? Full-suspension is *the worst* human power output design you can get off a bike, particularily on those y-frame bikes. You'd be marketing what would be in essence a toy bike without any real bike on it, packing extra lbs with no way to enjoy the ride without the motor, none of the real amenities you need to actually *go* off roading.

Doesn't get any more sealed than a hub motor:

http://video.google.ca/videoplay?docid=2830041791628409013

Randy: So you're claiming this bike will go 30 miles on how many watt hours? At what speed?

From personal experience i'll let you know that a Crystalyte 4 series can both be sealed, and withstand considerable punishment. The 408 has taken a Canadian winter and several trips to some of the more technical trail the rockies have to offer without any maintenance or damage. A BionX is superior still, it comes in around the same weight as the frame motors once you add in the additional freewheel, is made of aluminum, and has the same strength as any other hub will offer. One advantage that rear suspension gets you in this case is that the dynamic load on the motor is considerably lessened during impact with the ground after getting some vertical motion :)

I suppose you *could* build a bike that way and have it come in at 37lbs. But you're going to send your customers off to do offroading without mudguards or derailleurs? Full-suspension is *the worst* human power output design you can get off a bike, particularily on those y-frame bikes. You'd be marketing what would be in essence a toy bike without any real bike on it, packing extra lbs with no way to enjoy the ride without the motor, none of the real amenities you need to actually *go* off roading. Considering that I DO get a full 20 miles on a ROUND TRIP at a average of 20 mph on a heavy 45 lb Huffy plus a 5 lb motor and a 7 lb battery pack= 57 lb ebike using only 3 speeds for pedaling and or 1600 watts of power on demand at over 92% efficiency throught the whole speed range a trip of 20 miles at a 20 mph AVERAGE speed without pedaling has been done on video with 45 mph top speeds. Going slower (18 mph) for 30 miles with a 37 lb ebike would be no problem. Why have any derailers when you can get better than 24 mph in 5 secoonds without any ? A heavy unsuspended hub motor would break spokes (if not the motor) on the first off road bump you hit hard.. Certainly not for ebike motocrossers. Better stick to flat smooth roads.What other real amenities do you need to actually *go* off roading besides a couple cheap plastic mud gusrds ?. A Toy ?

Doesn't get any more sealed than a hub motor:

http://video.google.ca/videoplay?docid=2830041791628409013

Randy: So you're claiming this bike will go 30 miles on how many watt hours? At what speed? On 8 amp hours at 36 volts (from a 12 ah battery)= 288 watt hours (9.6 wh per mile)= 30 miles at a average speed of 18 mph on most round trips ANYWHERE! WITHOUT pedaling on a 37 lb ebike, regardless of wind or hills it averages out.. now YOU have figures to beat.. lol

now YOU have figures to beat.. lol

That's the problem - you treat every eBike effort like a competition! I'm very skeptical of someone who thinks that you gotta "beat" everyone to build a good eBike. Your whole "thing" has been based on winning regardless if it's fair, honest or at very least - a balanced mental effort.

Of course you'll backpeddle, shuffle your never-ending claims around in whatever order or amount suits you. Enter races you have no business entering, knock every other design while disregarding that some available products have a legit application and have brought this effort of eBiking to reality.

What have you brought to reality - another ban from a forum? Your narcism is like someone who alreay has these amazing motors in production along with 30lb, 30mph, 30 mile range eBikes! Such BS...

I feel for you, I really do - you must need the gratification, attention or something that you don't get in your life. But, it's hard to respect someone who tries so hard to impress - with words and little or no actions.

Considering that I DO get a full 20 miles on a ROUND TRIP at a average of 20 mph on a heavy 45 lb Huffy plus a 5 lb motor and a 7 lb battery pack= 57 lb ebike using only 3 speeds for pedaling and or 1600 watts of power on demand at over 92% efficiency throught the whole speed range a trip of 20 miles at a 20 mph AVERAGE speed without pedaling has been done on video with 45 mph top speeds. Going slower (18 mph) for 30 miles with a 37 lb ebike would be no problem. Why have any derailers when you can get better than 24 mph in 5 secoonds without any ? A heavy unsuspended hub motor would break spokes (if not the motor) on the first off road bump you hit hard.. Certainly not for ebike motocrossers. Better stick to flat smooth roads.What other real amenities do you need to actually *go* off roading besides a couple cheap plastic mud gusrds ?. A Toy ?

A toy?
I think you should go back and look at the dirt monkey, which was regarded to be a great offroader. Or go look at how you can pick up a hub motor without a prebuilt wheel and put it on any kind of rim you want to, including tougher spokes if you fancy. *Or* you could've read the part where i've personally rode a Crystalyte through a Canadian winter (heavy moisture, salt, cold), or looked at the video of the dirt monkey riding through a *lake*.

You shouldn't be calling something a toy unless you can suddenly prove that the video that was just posted was completely fake, that you *cant* put a hubmotor on a *very* good rim, despite being on Crystalyte's homepage and available from dealers everywhere as a project kit, or that you've personally put a frame mounted motor on an e-bike and successfully used it through sub-arctic conditions which I doubt you've done, mr. hawaii.

There's a difference between bias and blindness, having a personal preference for one styling is fine, but you're completely denouncing hub motors as nothing but a heavy, inefficient, fragile toy without seeming to know much about them at all.

Know what you need to go off roading? Well, you need reliability. You need to be able to fix something when it breaks down. You need to be comfortably familiar with what your gear can and can't do, and you need to know that what your gear *can do* is what you're doing.

I've taken my setup out and offroaded for fun, but its not a great field for an ebike no matter what way you slice it. You might say that the Crystalyte wouldn't stand a huge drop, no, it probably wouldn't. But guess what? Neither would a huffy, these bikes are meant to appease city kids who think full suspension is cool and that this bike rides smooth. Go ride a huffy off a 4 foot drop onto some hardpack or god forbid, rock floor some day, you'll learn the difference between an $80 hunk of junk and a $1500 bike. Without some heavy additions of casing and sealing, your motor wouldn't take being dipped in mud or run through a river.

For all purposes, when we're talking about riding trail or light/moderate cross-country, hub motors can take it. Freeride/Dirtjump/Downhill and so on? No, wouldn't think so. But thinking your huffy could handle it?

The very notion that you'd be willing to denounce a setup with a purpose built frame, designed with reliability and strength, reinforced spokes on the rear with a sealed system, derailleurs and proper gearing to carry you through *any* terrain, regardless of failure (or even if heaven forbid, you just want to ride your bike) and proper protection from wheel thrown mud or objects

for..

A huffy with no gearing, and what I suppose you think is a super light, invincible propulsion system,

is ludicrous.

If you want to go build a proper offroad e-bike, don't screw around with huffy. Don't make people miss out on something that is pretty much considered a necessity. Instead of wasting weight on 12lbs of useless toy frame, put the money out for something that will actually make getting a frame mounted system worth your time. You want to save weight? Get a decent hardtail or buck up for a great FS bike, don't play with junk and claim its an extreme offroad machine. Then, take that weight you saved, and use it for *useful* things. I could ride a tricycle down what you seem to think is hardcore singletrack.

This is way off topic now, kids :)

A toy?
I think you should go back and look at the dirt monkey, which was regarded to be a great offroader. Or go look at how you can pick up a hub motor without a prebuilt wheel and put it on any kind of rim you want to, including tougher spokes if you fancy. *Or* you could've read the part where i've personally rode a Crystalyte through a Canadian winter (heavy moisture, salt, cold), or looked at the video of the dirt monkey riding through a *lake*.

You shouldn't be calling something a toy unless you can suddenly prove that the video that was just posted was completely fake, that you *cant* put a hubmotor on a *very* good rim, despite being on Crystalyte's homepage and available from dealers everywhere as a project kit, or that you've personally put a frame mounted motor on an e-bike and successfully used it through sub-arctic conditions which I doubt you've done, mr. hawaii.

There's a difference between bias and blindness, having a personal preference for one styling is fine, but you're completely denouncing hub motors as nothing but a heavy, inefficient, fragile toy without seeming to know much about them at all.

Know what you need to go off roading? Well, you need reliability. You need to be able to fix something when it breaks down. You need to be comfortably familiar with what your gear can and can't do, and you need to know that what your gear *can do* is what you're doing.

I've taken my setup out and offroaded for fun, but its not a great field for an ebike no matter what way you slice it. You might say that the Crystalyte wouldn't stand a huge drop, no, it probably wouldn't. But guess what? Neither would a huffy, these bikes are meant to appease city kids who think full suspension is cool and that this bike rides smooth. Go ride a huffy off a 4 foot drop onto some hardpack or god forbid, rock floor some day, you'll learn the difference between an $80 hunk of junk and a $1500 bike. Without some heavy additions of casing and sealing, your motor wouldn't take being dipped in mud or run through a river.

For all purposes, when we're talking about riding trail or light/moderate cross-country, hub motors can take it. Freeride/Dirtjump/Downhill and so on? No, wouldn't think so. But thinking your huffy could handle it?

The very notion that you'd be willing to denounce a setup with a purpose built frame, designed with reliability and strength, reinforced spokes on the rear with a sealed system, derailleurs and proper gearing to carry you through *any* terrain, regardless of failure (or even if heaven forbid, you just want to ride your bike) and proper protection from wheel thrown mud or objects

for..

A huffy with no gearing, and what I suppose you think is a super light, invincible propulsion system,

is ludicrous.

If you want to go build a proper offroad e-bike, don't screw around with huffy. Don't make people miss out on something that is pretty much considered a necessity. Instead of wasting weight on 12lbs of useless toy frame, put the money out for something that will actually make getting a frame mounted system worth your time. You want to save weight? Get a decent hardtail or buck up for a great FS bike, don't play with junk and claim its an extreme offroad machine. Then, take that weight you saved, and use it for *useful* things. I could ride a tricycle down what you seem to think is hardcore singletrack.

This is way off topic now, kids :)The secret is in the light weight propelsion system not neserlary the the bike.The bike depends on what suspension performence you desire.The lighter the better as long as the suspension is adiquate for the speed and bumps.Not so off topic as you may think.