Electric Hub Motors ... ???

I applaud you for wanting to commute by assisted bike, being green, getting exercise at the same time. But, I think you are asking a lot from a transportation option that would be really hard pressed to meet your wants.

What I've learned in the short time I've been riding an assisted trike -

1. Faster means a more powerful motor - either electric or human, or both.
2. Faster means a bigger/heavier or bigger/very expensive battery pack. VERY EXPENSIVE
3. Faster - on a bike frame meant for lighter riders, but ridden by a heavier rider with a motor and battery means frame failure down the road, while on the road. That frame isn't gonna break in the garage. Chances are it will break with a pickemup or garbage truck or gas tanker behind you. You don't want that and none of us want that for you.
4. Farther means very hard pedaling on your part plus # 2.
5. Farther means that at some time, you may want to try solar to help charge your battery as you ride, thus getting you farther down the road.
6. Farther means you may be tempted to try a small genset on a trailer rather than solar.

So, what have I tried/learned? A delta trike (2 wheels in back) with a hub motor up front and solar panels on the trike and trailer to boost range. I started out with sealed lead acid batteries, a Wilderness Energy 20" wheel up front at 36v 400w, which was good for 15 mph no pedal, 20+ with pedal, range of 12 miles no pedal, 20 pedal. When I added 50# of solar panels, I once got 33 miles, but I was pedaling my a** off and it was a lot more work than just riding my unassisted trike. The solar would give me 36v 45w - so, about 12% increase in range. Sure, I could have gone with larger panels at $400 - $900 each, multiplied by 3 to get the 36v I needed. A losing battle, but very green! Somehow, on a 90 degree day, it just wasn't what I thought it would be! I wanted more speed, so, I went to 26" wheels all around and a Crystalyte X5 motor running at 36v. First day out, I bailed on the throttle at 25 mph, although I'm sure it would have pulled up to 30 or more had I waited and pedaled harder. The solar trailer started fishtailing - had that happen once in 1975 when towing my Alfa Romeo race car up to Road America. Not fun then, less fun now. A few years ago, at the Midwest Recumbent Rally at the Hostel Shoppe in Stevens Point, Wis., I saw a guy riding a Sun USX with a Cyclone motor assist, towing a trailer with a gen set on it, plus his dog, in a transport cage on the trailer. Poor dog! Gassed and deafened by his loving master!
I'm adding LiFePO4 batteries, 20 Ah, but the pack is rated at 1.5C, which may not be high enough, maybe I should have gone with NiMh at 3 or 5C. Time will tell!

I think the people that have been telling you that if you want to go fast on electric power, get a scooter have a good point. You may not like the idea, but riding with a 2 hp (36v) or 4 hp (72v) hubmotor is a real handfull, especially if the motor is up front. You won't get the benefit of the heavy (25# or more) motor's gyro effect until you are moving at a good clip, and up until that point, it is a beast that can have a mind of it's own! I've 'burned rubber' at a standing start - little weight up front on a delta trike, and when the pavement is damp - it seems like there is an evil force up front just trying to get me sideways and turned over. Then, there is the issue that any assist motor over 750 watts (1 hp approx.) is illegal, Federally and assisted bikes traveling over 20 mph - ditto. Will you end up on 'COPS' or'SPEEDERS' on cable tv? Probably not, but being in California, Eric Estrada could be around any bend, radar in hand, waiting.

It's your choice to make, and you could probably do it by lowering your expectations on speed. From your photo, I'd guess that you are a 'mature' adult like me (sounds better than borderline geezer, right?) and should have gained respect for how long road rash takes to heal, let alone broken bones. Temper what you want with what is safe and practical and enjoyable. And have a good ride!
 
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A basic hub motor and 48v. should be ok...

I have a no name electric hub motor and 48v of sla batteries on a "townie" or "cruiser", and with them I go as fast as I would possibly want to. I have to keep the brakes in good adjustment and have to anticipate driving patterns carefully at the speed it goes. Unless he's a professional racer, your son won't be keeping up with you when you throttle up. I haven't had a peddler on even the skinniest tire bikes keep up with me ever. I don't know, and don't want to know, how fast I'm going in mph., but I assure you, I'm going fast enough for anyone on that style of bike.

I would say that 98% of the people who see me don't even know I'm motorized unless I stop peddling and keep accelerating.

The batteries weigh a ton, (well, 40 lbs.) so they required a good quality bike rack, and that too, affects handling.

The motor is powerful enough that I destroyed the first fork I used it on, (and my right shoulder). I remedied that with a 5" piece of steel that I got for free and fabricated a torque arm. Look for torque arms on this forum, and that should give you an idea of what to do.

For an idea of how fast those motors are, just take your bike to the top of a significant downhill and launch yourself in high gear. When you can no longer peddle fast enough to keep up with the bike, that's how fast a basic hub motor with 48v. will take you on your townie. As for distance, I have a 8 mile commute, and forgot to charge one night, so I got to work and back, at least 16 miles, but I don't know how far it'll go. I weigh more than you!

Wear a good helmet.

Bob
 
Electric will do the speed your after and a **** of alot more whether you want to be on a bicycle doing that speed is another story. The range your wanting is also very doable.... I would recommend not getting a hub motor and going with a Cyclone setup or similar... If you want to stay legal 750watts i believe is the legal max in USA and your limited to 20mph ... You will need a 36 or 48volt setup with 15-20ah capacity.... Lifepo4s are the battery s to get and Ping is the man to get them from his web addy--> http://www.pingbattery.com/servlet/StoreFront

He is one of only a few using the latest prismatic "pouch" type cells in his packs, the majority are still using the round cells which are problematic, Ping has a good track record, when his packs do encounter problems he has always done whats required to rectify the problems by all accounts thus far... the whole setup could be done for lil over $US1000...More than it would cost to fit out your bike with a 48cc but it
will last you a good 4-5 years before you will have to spend any more on it if all goes well...no pollution, no noise, more torque, more top end if you can afford the outlay its the smartest option ;-)

As nice and as helpful as the fellas are here at motoerdbikes the site is obviously more geared around petrol motored bicycles and thus the input for those interested in going electric is rather minimalistic and from what i have read in this thread alone often misleading... http://endless-sphere.com/forums/index.php is the forum to be on if you want the latest info on electric bicycles...

best of luck with your project...

Regards

Kim
 
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I started out with an electric hub on my girlie cruiser. It was quick and top speed was 27 mph. Range was a whopping 54 miles on a charge, thanks to 80 pounds of relatively affordable lead batteries I carried on the bike. It was clean, quiet and docile.

Disadvantages? I live in a walk-up apartment and had to remove and reinstall the batteries on a daily basis to carry them upstairs to recharge. That was also the only way I could carry my 125-pound cruiser bike to my apartment.

The quest for more power and less weight would have been a set of LiIon batteries. To keep the range I had now would've cost over $1K in cells. Then I pobably would've upgraded to twin hub motors, controller and MORE expensive batteries which eventually would need to be replaced.

The reason I finally switched to gas was that I could FEEL the brand new bike's frame FLEXING occasionally at walking speed. It had too much weight to carry, and it felt like "the tail wagging the dog."

Regretfully, I removed my electrical system and installed ICE (internal combustion engines). I can push/carry my single-engined cruiser up two flights of stairs. With my dual-engined monster, my wife pulls on its horns with a double-leash and I lift/push its 80-pound tail slowly up the 20 steps. Thank God I only do that when the monster "Mr. Hyde" needs attention. Otherwise it sleeps in the stairwell below. I just need to feed its tanks with pre-mixed fuel and away we go. Its range is a little more than what my electric bike was. However, when it's time to refuel and I'm carrying a bottle of oil, I just pull into any gas station and fill the reserve tank.


My big questions are:

Will you be able to carry 80 pounds of batteries and recharge every 54 miles? Your round trip is 30 miles and that's AVERAGING less than 20 mph. As time erodes the batteries' range will also decrease.

Will your family object to your recharging in your tiny apartment on a daily basis? You'll also be recharging on days you don't work.

How much are you willing to invest in this electric moped you're creating?

Do you like to tinker? I hope so, because you will not have any support or repair shops who can assist you in repairs and tech advice.

You are not in top physical condition, which is another reason to rethink this. You can muster 6-7mph pedalling, and you expect your bike to push you over 30 mph.

No disrespect meant, but you don't have what it takes to create, maintain and feed this electrical hybrid. The bicycle you build will weigh MUCH more than a Puch or Tomos, and almost as much as a Honda or Arnada moped. It will also not have the speed, durability or performance and safety equipment as a moped. The bike's frame will flex, its brakes will not be up to par and I doubt if you'll be upgrading that.

If you're not "green", if you're 51 years old with medical issues and not in the best of health, if you intend to ride a bicycle 30 miles daily to work, then you must have problems with your traffic abstract (driving record) or cash flow.


I see big trouble ahead with either a gas or electric conversion. A bicycle will sap the energy out of a sickly person.

I just re-read your first post. I see big trouble ahead. The bicycle and your body cannot handle your delusional demands and expectations.

How about a car?:unsure:

Or carpooling?
 
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Basically, he's trying to get away with....

He's trying to get around without a license. I'm sure of it. His best bet is to find a STEEL construction bike and then add a HUGE LIFEPO4 Battery to it. I would say if you buy a 36v 60 AH lifepo, then you can get about 60 miles out of it and spend 1200 bucks. Other then that, just get a scooter. You'll be happier in the end.
 
Among my fellow co-workers, I'm in good shape, twice their age at 62 and think outside the box. With over 100 welfare workers in our building, two of us bicycle to work. :sick:

I give my female counterpart credit. She slices thru the heart of 6 miles of a VERY heavily congested and hilly metropolis on a pedal bike, but she's healthy and half my age.

I LOVE to ride my MB to work. I have a 12-mile round trip I really enjoy three times weekly at most. If I had a 30-mile route, I'd still enjoy it three times a week.

I would also rotate two fully-equipped bikes if I was determined to do this.

As a healthy young guy, I'd ride a motorcycle or car.

As an old guy with several medical and physical problems, I'd drive a car or carpool...period.

The only reason that I don't ride to work daily is because I attend night classes. With the bad roads and crazy drivers, it"s too much of a risk to ride at night.

If not, I think I'd enjoy riding my MB twelve miles to work on a daily basis.

Sir, my final word of advice from an older man(me) to an old man(you) is to abandon this idea and find a SAFER way of commuting to work...

or move closer to work.
 
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Aussie, my build was in 2004, so unsure if that powerpack was available and affordable.

Besides, I really didn't know if I was gonna stick with an e-bike. If I had a house with a garage, I probably would've kept it longer.

The carrying and recharging wore me down. Lugging my monster gas bike was also wearing me out, until I realized that it liked to sleep outside.

"I rode the beast to McDonald's inn for breakfast and chained him to a tree, where I could watch over him. I was dining on milk and sweet breads when the old woman called and asked me to bring her soup and fruit. So I led the monster to yonder market and chained the lumbering beast to a post outside, away from innocent passersby. After marketing, I filled its basket with a gallon of milk, five large containers of soup, three oranges and grapes. Along with my large tool pouch, the morning chronicle and a flask of water. The monster shook and wagged its heavy head while I beckoned him to arise. Once I led the beast off the path and onto the clearing, we roared off and flew effortlessly up the hill. As we landed, I stroked its sides. He was warm to the touch and smelled good, like burning sulphur. His mighty roar changed quickly to a healthy rumbling purr, and then it slept. I removed its heavy load from its head and chained him to his rack.

It enjoyed resting under the stairway, and waited patiently to be summoned, again and again."
 
maybe you should consider keeping your townie a bike and get a scooter for your commuting. That way you could pedalaround with yiour boys in your neighborhood for exercise and the scooter would be fun to ride and give you the speed amd range you need
 
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