New, Need Advice Thanks

I

imagesinthewind

100 mW
Joined
Jun 10, 2015
Messages
42
Location
Denver, CO
I'm Ginny in Denver, CO USA.
I have bad knees and cycling the inclines we call hills that are really mini mountains is getting
difficult. I'd like some assistance with this.

My bike is a 2011 Sun EZ Sport AX recumbent, 2 wheels.
26" rear and 20" front.
My main objectives are to have some assistance in climbing hills that can be several miles at 6-10% grades, not just powering up
the hill. I still want to do most of the work, but some assistance to stay above 7mph would be good. I currently pedal those at about 4mph and
cannot sustain over about a mile. Part of that is the shape I'm in but that's in the works, after 2 knee surgeries, I'm getting back into the swing
of cycling.

I'm not really worried about flat max speed, my bike and I are good at about 20-22 mph on flats. Recumbents geometry is not great for climbing.
My brakes are V brakes, I have a 9 speed rear cassette, 3 up front.
My bike weighs about 32 pounds, 40 with the water, Bose speaker (I don't ride silent), rack. I'm about 153ish depending on the day.

I don't know if I want a front wheel motor or rear wheel and I'm not sure on budget, I don't even know what is out there.

My husband has a Copenhagen Wheel on order, his order number says he's in the first 700 wheels to be shipped, but they have been pushing back
the shipping date for 16 months. And that is a commuter wheel and not a climbing wheel. I need something that will give me assist when I
need it going up, a little assist on flats to make up for the weight of the motor and battery. I also want the battery to last 4-7 hours.

I hope that's the info you need, I've been in contact with Paul of EM3ev and was looking at the MAC 500W/1000W Pick N Mix.

I'm totally new to this, but I work on my own cars and am pretty good with a wrench, I learn fast.
Thanks for any advice on what to get and from whom. I have an on-line friend with a Falco rear wheel on his recumbent trike (two front, one rear wheel)
and he loves it.

Thanks
Ginny in Denver
 
take Paul advice as a main, he is a really high reputation expert.

For saying anything to start, if you want a 1000W build, and specially for hills, if you want a hub motor, rear is the best place to avoid wheel drift.
 
First off, it's very astute of you to realize that once the system is installed, some assist will always be needed due to the drag of the oil seals, weight, etc.
Many noobies come on here with the same assertion, "Ï will only use the system on the hills".
I wouldn't usually recommend a mini to someone in CO. and I'm sure some will suggest big motor.
But if you are in the ball park about the grades and your ability to input, I think a frt. mini is the right approach.
It's been done with success before.
Idlemind converted his home made gas powered recumbent to electric using the Cute motor, sine wave controller from BMS Battery.
http://endless-sphere.com/forums/viewtopic.php?f=2&t=61982
He made his own battery, but that too, can come from BMS Battery. In fact, everything can come from them and that will save you money.
Look at their Li-Ion 36V batteries and think about capacity(you will get at least 2 miles per Ah, probably more like 3)and what will fit your bike.
https://bmsbattery.com/70-36v-li-ion
oRead(down-load manuals) about the SO6S controller and SLCD-3 display. Tons of high-tech features and the "Torque Imitation" with 5-level PAS would be perfect for your application.
Go to Ebike CA's motor sim and plug in the relavent componetes(15 A custom controller, Q100 328 in 20" whl., etc. ) and ck out range, top speed and climbing ability, all good for you;
http://www.ebikes.ca/tools/simulator.html
We tend to think of battery range in terms of ground covered, not time. You have lot's of mounting options and can go big, but use Li-IOn to keep the weight reasonable and try to mount low(dual Batt. would be an option)
Cavets;
The dropout width of your forks need to be 100 m,m.
This system is not "build from scratch" and it is not a "bolt on". It's in between. Some time fitting the sensors and programming the display is required.
But if you are "techy inclinded", it will not be that difficult and you might even enjoy it.
Plus there is ton's of SO6S/SLCD-3 info(and help)here.
 
I sure didn't like a frt hub on my Burley. Rear was much better.
As for a rear hub, you might have a problem fitting a 9 speed on your bike without spreading the rear dropouts. If they are steel should be no problem I alloy don't do it.

As for a rear hub with low drag a MAC is great. 10 or 12t will climb you Mini Mountains like a goat. I would also recommend a 50v battery over the 36v. As posted above Paul is one of the best to help on this. System is all plug and play, after you install the parts. It is also great quality. A little more expensive than BMS but you will get what you need the first time and no surprises after you order.

Dan
 
Rear hub. Just about any 750w 36v motor kit, or 48v 1000w kit will do it great, allowing a moderate pedaling effort to keep you going 12-15 mph, even up those kind of hills.

I live in the southern rockies, and have ridden up such hills, so I know. The mac or other similar motors a great choice. But if you really want 1000w, but a motor that is a durable direct drive, and still has a top speed of only 20 mph, then I only know of one choice. It can have a 9 speed. This type of hub motor has a lower rpm than others, so when it slows going up a hill, it gets less hot. Heating the motor is wasted battery capacity, or worse, melting the motor. One thing I love about the slower rpm direct drive motors, is that they do drag when you descend the huge mountain. That's kind of nice, I don't want 50 mph down a mountain anymore. For me, for rocky mountain riding, it's perfect. Efficient up the hill, helps me slow down on the way down.

Forum rules prevent me from saying where you can buy one, but others can.

Other generic 48v 1000w motor kits will do the job, they just will have a fast maximum speed. But the same motors run on 36v will also go about 20mph, and 750 watts can be plenty if you just pedal briskly, without over doing. Even the faster direct drive motors will still slow you some on the descent.
 
dogman dan said:
I live in the southern rockies, and have ridden up such hills, so I know. The mac or other similar motors a great choice. But if you really want 1000w, but a motor that is a durable direct drive, and still has a top speed of only 20 mph, then I only know of one choice. It can have a 9 speed. This type of hub motor has a lower rpm than others, so when it slows going up a hill, it gets less hot. Heating the motor is wasted battery capacity, or worse, melting the motor. One thing I love about the slower rpm direct drive motors, is that they do drag when you descend the huge mountain. That's kind of nice, I don't want 50 mph down a mountain anymore. For me, for rocky mountain riding, it's perfect. Efficient up the hill, helps me slow down on the way down.

Forum rules prevent me from saying where you can buy one, but others can.
Click to expand...
Must be E-BikeKit's Heavy-Duty 500w-1000w, 36v/48v Compatible , 600lb Load Limit conversion kit here:
http://www.ebikekit.com/electric-bi...attery/direct-drive-hub-motor-conversion-kit/
 
If I went with the ebike kit, which I love for the slowing down long hills (saves brakes, I bet as well as my sanity) but wanted to have a long riding day,
what is the aH I'm looking for for say a 5 hour riding day? 60-75 miles with some climbing.

Can I do a 1000W 48V 20aH battery in this kit?
http://www.ebikekit.com/electric-bike-conversion-kits/rear-500w-direct-drive-motor-kit/

What is my limit on aH for this kit?

Also, my husband thinks a motor without regen capabilities is not wise for my application. If he is wrong, why? If he is right, why?
We have two Nissan Leaf cars in our driveway right now and I can drive to get some decent regen in the car, like going 15 mile but
only using 1 mile of range...why can I not do that with ebike motor?

Thanks! I'm learning a lot!

Ginny
 
http://endless-sphere.com/forums/viewtopic.php?f=3&t=70169&p=1058597#p1058597
 
for 60-75 miles of riding, I carry at least 1500 watt hours. But if you will be climbing more than 3000 vertical feet, you'll need 2000 watt hours or more. 48v 20 ah is 1000 watt hours. No limit on the amp hour size of battery you can use, but there are definite limits to how much battery can be comfortably carried on a regular bike. Anything more than 30 pounds of battery will be very difficult unless you have a cargo bike.

Look for a smaller and lighter 48v 20 ah battery. What we sell at E bike kit will be too small for your needs, and Lifepo4 is heavier than other types of batteries. With a good 1000 watt hour battery that weighs less than 15 pounds, you will be able to ride 40-50 miles.

Your husband is not wrong. Regen is worth it for a heavier vehicle. That's why it was pioneered on mine trucks the size of a house. The bike is just so light, regen braking puts very little back compared to a heavier vehicle.

Re the regen, it's just not worth having your nuts loosen on the wheel, and having the wheel fall off. It can be done so this can't happen, but it requires lots of modification to the bike. Regen on bikes is not worth it for the energy back, what you put back on a long downhill is less than you get by just pedaling for 1/4 mile on a flat section. Burn 500 watt hours going up a mountain, get 12 watt hours back using regen back down. With regen engaged, maybe you get 4-5mph as you descend. A slower descent is great, but not THAT slow.

Regen mostly gives you a third option for stopping without brake wear. But it could be worth it, if you were descending the rockies with a 450 pound total weight. I liked regen for that, with my cargo bike loaded with batteries and camping gear.

But just a rider on a normal bike, you will find the slower rpm direct drive motor I suggested will slow you enough on the downhills
to save your brakes quite a bit. If you like to descend at about 20-25 mph, you won't touch your brakes much at all on a 6% grade. And you won't need them near as much on a 15%.

That slower rpm motor will climb the hills more efficient, saving a lot more battery than you typically get from regen. So in a way, it evens out in the end. But the motor IS able to regen. It's just the E-bike kit controller that does not support regen. You also have to be sure the batteries battery management system will support regen. Most bms want charging input through one set of wires and discharge through another. So it may not be ideal to put power in, back through the out wires. So that's another potential complication with regen. Your leaf battery is built for it, but bike batteries may not be.
 
If you have long steep hills, you should probably check out the motor simulator http://www.ebikes.ca/tools/simulator.html to understand what'll happen going up hills with a hub motor. Basically, electrical motors are fairly efficient, maybe 90% or a bit more in the sweet spot for a good one. That sweet spot is in RPMs. Since hub motors don't go through gears you can change, the RPMs correspond to a certain speed on your bike. So there is a sweet spot of speed. If you go slower then efficiency drops. Going 12 MPH instead of 20 MPH might drop your efficiency to 66% instead of 90%. That would mean 34% of the energy going into the motor is being turned into heat. Electric motors can overheat, and at those low efficiency numbers with 1000-2000w going into the motor, it might overheat in a matter of minutes.

For short hills, thats ok. For long hills, like a few miles, its not. That leaves a couple of options.

1. Ensure the system you choose can power you up the hill at an efficient speed. As you can imagine, taking you + 40lb of bike + XXlbs of battery + motor going 20mph up a 15% grade takes quite a bit of power. You might need a 30A or 40A controller and battery for your application. Batteries that can put out more amps can cost more.

2. Get a motor that can use different gears. For instance the mid drive BBS02, you can just change gears so the motor is always efficient.

Personally I think you should consider the BBS02 mid-drive system from Bafang. Its a very pedal-friendly system, with pedal assist built-in and no motor drag, like the direct drive motors have; it's pretty light, on par with the smaller hub motors; but capable of very steep hills with lower power batteries. Also, you can go up the hills at a similar pace to other human powered only riders, if you care.

Some people are getting 15wh/mi with the BBS02, at your desired range of 75 miles would mean a 1125wh or 23.5Ah battery. But really you shouldn't design the system to discharge it 100%. Bottom line, you'll need a really big battery or to do a lot of the work over those 60-75 miles yourself.

You can look at some of the Wh per mile threads like http://endless-sphere.com/forums/viewtopic.php?f=28&t=61167 to get an idea for various system types like a DD hub or BBS02, although obviously there are lots of factors that go into the Wh/mile.
 
True enough, the bafang would be more efficient up mountains that big. But if they are getting 15 wh/mi up the rocky mountains, they are pedaling their guts out. On moderate hills, I can easily get 15 wh/mi, with a gigantic 5304 hubmotor. But over the mountain and down the other side, the average is more like 25 wh/mi. That's with a bike weighing 350 pounds including me.

But one downside with the BBso2 is you only get one , fairly large chain ring on the front. But, with power, you can then climb fast enough to only need that big ring, even on some pretty steep hills. Just get a cassette with a gigantic gear on it on the back.

With the slow dd motor, she will be able to ascend a hill slower than with faster dd motors and stay reasonably efficient. but she will still need to run enough power to keep moving at 12 mph, vs the 15 mph required to stay reasonably efficient up a long hill with the faster winds.

Either way, bottom bracket motor or slow direct drive, you will need to run a pretty high wattage to climb slumgullion pass at 12 mph. So up big mountains, figure a 48v 20 ah battery will get you 15 uphill miles. In truth, it's just hard to carry enough motor and enough battery, to really keep up with a truly fit, nearly professional bike rider. But you can beat them to the top on a large hill, and have lunch while they toil up the thing. 8)
 
Between Dan and tln, I think I'm getting to understand...Thanks to both of you.

Let's say I was to bike up the hard side of this: https://en.wikipedia.org/wiki/Slumgullion_Pass

I do not want to power up the hill. I want to be able to ride for as long as my knees and legs allow and then get some PAS when my body
tells me it's time to walk. 12 mph is faster than I would want to go. I want to do 75% of the work with just a little extra help. I may be
asking too much of a motor, I know. I'm looking for 7 miles per hour up the hill. At this point in my training, I would not make it 1/2 a mile
up that hill. But I have a year to train. My worry is that during training rides I will push a bad knee into a very bad knee. My surgeon is already
talking abut when a replacement will be done, but I'm a very young 48 (I act more my shoe size) and am not ready to do that. Pushing my
knee might just hasten that surgery.

I do love the idea of the motor slowing me down on downhills. My son, then barely 15, did the backside into Lake City alone, in the rain, and traffic,
trying desperately to stay slow enough not to slide out on the switchbacks but also not burn out brakes. He was supposed to stay with someone
on the downhill, but there was no one was at the summit when he started down. He cried at the bottom. When I mentioned a motor that could
have slowed him down, he wished he had that on that day. He's 20 now and that day still stands out as a rough moment.

I like the idea of using my gears and cadence to determine how much motor assist I get. Have a single chainring in the front is fine, I stay in my
middle ring most anyway which i believe is a 42T. I only go into the 30T on the bill hills and at the end of the rides when my legs/knee are spent.
But using my gears is a better way for me to go.

Paul at EM3ev pointed me to both the MAC and the BBso2.

Lastly, I look at the weight of the motor and battery as if it was just me being 30 pounds heavier, which I used to be. When I got in really good
shape in 2013, I lost 30 pounds of fat, when from a size 12 to a size 7 and then my knee went nuts. I've kept most of it off but have lost the muscle
I am not trying to build back up.

This is my bike, btw... http://www.electric-bikes.com/betterbikes/details/ez_sport_ax_d.jpg
ez_sport_ax_d.jpg


Thanks again, keep it coming if there is more to say.

Ginny
 
I think the front or rear 48v Xiongda kit would be perfect for what you want as long as your forks are standard 100mm. It has a gear system that allows it to automatically (or manually) change internally to a lower gear for hill-climbing, so it can remain efficient and cool, while climbing very steep hills. It's relatively small, light (3kg) and free-running, so it won't spoil the normal pedalling of your bike. Top speed is about 22 mph.

Xiongda provide everything you need in the kit except the battery for about $300 including shipping. It might be a good idea to get a torque arm for it to help your drop-outs resist the torque. You get a nice LCD that shows speed, distance,power and things like that. You can adjust the pedal assist power through six levels from zero to maximum or use an independent throttle. You can buy the kit direct from Xiongda or through their Alixpress listing.

The rear motor is relatively wide at about 142mm, so it's a tight fit in your frame, but no problem for a steel frame; however, your is aluminium. It'll still fit but you might need to stretch the frame a bit like I did on my two. The front motor would be a straight-forward fit.
 
Xiondga got back to me and the kit is about $250 shipped.

It seems like both a deal and a good way to go with the HAL switch controller.

I'm thinking that the front wheel would be better as my long wheel base bike already has a lot of
weight on the rear and with a hub motor and battery, it will be very unbalanced.

Does this motor have a brake shut off?

Thanks
Ginny
 
If you plan to ascend steep hills at 7 mph, then you need a motor that can do that. You'd fry the E-Bikekit heavy duty direct drive motor climbing the steep hills at 7 mph. Slow a hub motor too much under heavy load, and it just wastes power straight into heat. You'd have to keep going 12 mph (in 26" rim" with the EBK motor to stay in reasonably efficient rpm. Perhaps about 10 mph would be ok with your rear rim size.

You'd fry most planetary gear motors too, but the two speed Xiondga would be the hubmotor that could, if any. I've no experience with it, so I don't know if it could do real rocky mountain riding. I know it can climb the hills, but I don't know for how long non stop, at 7 mph. Again, the 20" rim will help. I'd still advise putting a hub motor on the back. Works great on my bent, which is similar in weight distribution. Put the battery forward though, if possible.

The bafang might be your best choice, allowing you to gear down the motor enough to go that slow up mountains, That slow, you'd also be using less power from the battery, and likely get the best efficiency.

Downside, neither the bafang or the xiondga will give you motor braking down the hill. So as before the motor, good pads for the big days.

Once a hub motor gets hot, bear in mind that geared motors don't cool well. The EBK direct drive cools itself pretty good, which is why our heavy duty kit is direct drive. Work a geared motor just as hard, and it will retain it's internal heat too well, and cook the hall sensors. So with the geared motor, even more crucial that you don't overheat one.

One last note, keeping your speed up to 10-12 mph with the dd motor will be easier to do than you imagine. But it will take power, so you won't be getting more than 1 mile per amp hour going up big mountains.

Best for overall efficiency will definitely be the bafang, imo. Because it can be run through your lowest gear, at 5 mph, and still have the motor spinning fast, cool, and efficient. But, I do love that motor braking you get from a nice slow wind direct drive hubmotor on a really big hill. So in some ways, I think you'd like the big heavy direct drive best in the end. But you'd need to plan on rides in the 20-30 miles distance, rather than 50+ miles.

Let your husband and friends start from home, then meet them halfway, carrying the bike on a car bike rack. Then enjoy the best part of the ride, and let them do 50+ miles.
 
attachment.php


This is my bike.
Where is a good place for the controller, with the hub on the front.
Yes, I am going to try it on the front first. There is already a lot of weight on the back and with the
battery, that will increase. Recumbents need balance.
 
My wife has the Sun USX trike after many ER visits due to 2 wheel crashes. She has an Ebikekit on the front and it helps balance. I use a rear Xiongda and it would get you up those hills too, on the front. Either would work but the Ebikekit is heavier by double, or about 15 lbs in the wheel.
otherDoc.
 
http://image.ec21.com/image/rohimajuwita/oimg_GC04352501_CA04352508/Electric_Bicycle_Easy_Racers_Tour_Easy_Recumbent_Bike.jpg

Electric_Bicycle_Easy_Racers_Tour_Easy_Recumbent_Bike.jpg


This is what I want in the end. This is a Tour Easy, the company that originally designed the EZ Sport bikes for Sun.

I'm just about done talking with Xiongda and ready to order. Just making sure the cables will be long enough to get where everything needs to be for ease of install.
I will need to find a new rim and spokes and put torque arms on the front as my frame is aluminum.

other doc, do you have photos? Where did you put the controller?

Thanks a lot!!

Ginny
2011 Sun EZ Sport AX
 
Quick release front wheel will probably be okay.
There's a "lawyer's lip", a raised ridge around a depression to retain the quick release locking nut. You'll have to use a C-washer (1 or 2) to fill the depression for the hub motor's axle nut to screw down onto the dropout itself rather than screwing it down onto the raised ridge.
The Tour Easy Classic webpage says the front fork is Cro-Mo so at least it's not aluminum.
 
That's good. Can I get a torque arm for this kind of fork?
I'm going to be asking a lot of the wheel on hills, don't want a broken fork.

If so, can you point me to the type I need?

Ginny
 
I would never use a front hub motor if you can fit one on the rear. They can break the fork. They will spin out easier on slippery surfaces to name the most critical problems.
 
wesnewell said:
I would never use a front hub motor if you can fit one on the rear. They can break the fork. They will spin out easier on slippery surfaces to name the most critical problems.
Click to expand...


Yes, I know. But my long wheel base recumbent needs the balance of weight.
All my research and talking with those who have experience with recumbents says
it's better for a front hub.

Thanks
 
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