Recumbent BikeE for Comfort and Efficiency

Recently I joined the recumbent owners club. This is an experiment, I have no prior experience with recumbents. My interest in them stemmed from the desire of going on some longer rides with friends. 100 miles on my mountain bike just seems like an ergonomic disaster to neck, lower back and wrists, and the higher aerodynamic efficiency of the recumbent should reduce the energy required for these long trips where battery is a challenge. The comfortable, relaxed "lawn chair" seating position of the recumbent design allows for longer rides without as much strain on the body. A geared hubmotor glides without resistance, and provides good climbing torque without the weight or high power of a DD hub.

So I picked up a used bikeE to try out. This may not be the final platform, but it seems like a reasonable start. The particular unit I have is little used and came with the manuals. It has been stored indoors and is in good condition. Here is a snapshot:



Here is the picasa web album for this project:

https://picasaweb.google.com/Alan.Biocca/EBikeEProject?authuser=0&authkey=Gv1sRgCOD0ns2Z9JSK-AE&feat=directlink

The rear wheel is 20" and the front is 16". The rear hub contains a 3 speed SRAM internal gearbox plus a 7 speed cog set. There is a single chainring in the front.

So, given that I want to have an efficient system for long range, and lots of pedal input, and moderate speed, I'm wondering how to e-power this bike? There are lots of choices. A rear Magic Pie? A rear Gearmotor? A front motor? Something through the chain? A left side chain drive?

I will need good hill climbing, up to 15% at times. The build will not start for awhile as I'm still working on some other builds. This will be #4.

edit: Correction. On 1 Feb this project was accelerated to be ready for 11 Feb Mega Monster Enduro. So it edges in front of the earlier started 'Borg build, and will finish in #3 position.

Updates:

2/11/2012 Failed to make Mega Monster Enduro, bikeE is almost electrified
2/12/2012 First Electric Test Run
3/7/2012 Maiden Commute Run with 48V 24AH Vinyl Tube encased Battery Pack

There are a number of similar builds here on ES (more than I realized), I link them here for reference.

Comments welcome.

Other bikeE Projects:

https://endless-sphere.com/forums/viewtopic.php?f=3&t=26412
https://endless-sphere.com/forums/viewtopic.php?f=3&t=29430
https://endless-sphere.com/forums/viewtopic.php?f=8&t=28061
https://endless-sphere.com/forums/viewtopic.php?f=2&t=26216
https://endless-sphere.com/forums/viewtopic.php?f=28&t=25980
https://endless-sphere.com/forums/viewtopic.php?f=3&t=25739
https://endless-sphere.com/forums/viewtopic.php?f=3&t=25739
https://endless-sphere.com/forums/viewtopic.php?f=3&t=25739 recumbent resources
https://endless-sphere.com/forums/viewtopic.php?f=6&t=4938 cyclone ypedal and http://ypedal.com/Cyclone.htm
https://endless-sphere.com/forums/viewtopic.php?f=2&t=4397 RX model
https://endless-sphere.com/forums/viewtopic.php?f=2&t=4397

Have you thought about your design goals with respect to top speed? As you probably know, a hub front wheel in the 16" size isn't going to have much in the way of top speed but should climb great.

With respect to the bikeE, I've had one and they aren't the most stable at high speeds either. They are nice in the city but at higher speeds they leave something to be desired. At 40mph my LWB recumbent is rock solid whereas at about 25mph my bikeE felt pretty twitchy by comparison.

You are facing some of the same challenges I've been wrestling with electrifying my tadpole trike with 20" wheels. I think I've finally settled on using a second drive chain to the rear wheel so I can take advantage of using a NuVinci hub but I could have done that with the stock IGH Sturmey Archer as well but I plan on using the NV gearing to help out with hills and tops speed. I still may end up going with the motor inline using the original drive chain but I am not sure how much power the original IGH can handle so I am playing it safe and going with the NV hub which can easily handle it from what I've read.

Good luck with your build. It should be interesting and climb hills amazingly well. I've spent 100 mile days on my LWB bent without any issues. The improved aerodynamics are even more noticeable on my ebike version. Add a small windscreen and you can pick up an easy 2-4 mph.

Thanks for your comments. I was just out pedaling it around the neighborhood. I can see the reduced stability. I'm not in it for speed. 25 mph is probably plenty. I'd like it to climb steep stuff at 20 or so, though.


Edit - 12/2014 Configuration Summary below

This will be periodically updated and located on page one early in the thread so folks can find it. It will summarize the components used on the project for those interested.

BikeE model CT
BMC V4C Gearmotor and rear wheel
Lyen controller 12 FET 4110 type
Thumb throttle
Cycle Analyst V3
4ea Zippy 6S 8AH packs wired in 12S2P for 44V 16AH (normal daily driver pack)
ebikes.ca torque arms and custom made torque struts, 2 ea
Schwalbe Big Apple tires
lights..
Underseat Pannier Racks
Topeak Trunk system
more detail later...

I wonder how much lipo would fit into the main frame member?

12/2014 edit - battery expansion - see page 8 - http://endless-sphere.com/forums/viewtopic.php?f=3&t=35954&p=983750#p983750

interior main beam measurement from page 2:
1-3/8" by 3-1/4" by 26" approximately available inside the frame.
converting
660x82x35 mm metric space
142x49x43 6S 5200 multistar won't fit
142x49x22 3S 5200 multistar would fit, fairly loose
142x49x29 4S 5200 multistar would fit, just about max width, about 4 batts long so 16S 5.2AH 300WH 13A 770W max
present pack is 12S 16AH Zippy 700WH
the limited current of Multistar is a problem here, though it would be okay for 500-700W

Alan B said:

Thanks for your comments. I was just out pedaling it around the neighborhood. I can see the reduced stability. I'm not in it for speed. 25 mph is probably plenty. I'd like it to climb steep stuff at 20 or so, though.

Click to expand...

Just remember to keep realistic goals, I tried to make something climb at 20+ MPH and still be a "legal" wattage bike, and it's not really gonna happen. :wink:

My dream is similar to yours, but I have come to the realization that steep hills like you describe (I regularly climb a hill here in Oregon City that is 5 - 12% and 2 miles long) is going to require a ton more power even with a mid-drive than the average build.

I plan to limit top speed with my CA, and have a bike that would probably hit 40+ MPH on the flat otherwise, to be able to hit speeds close to 15 MPH up steep hills.

Not saying it's not possible, just be aware that trying to get the speed you want up a steep hill is going to take 3,000 + watts sustained!

I think the Bike-E should be excellent for your purposes since you're not a speed demon, and I would suggest since you have the room, build a mid-drive, but another good option would be a MAC in the rear wheel, 20 inch wheel will require more voltage to get it going 20+ MPH on the flat, but should climb hills well with the right winding at around 48V too.

What ever you decide, take pics and post them! Great to see more recumbents here. 8)

Page 1 of 4... 8)
http://ypedal.com/Cyclone.htm

True. I'm interested in bike appropriate speeds but expect to use the necessary power to get there.

A BikeE isn't very aerodynamic, there are many better options. It might be a tad better than a mtb position, but not by much if at all.

Nice looking bike. That is the my preferred era Bike E. Just like me though, later you'll probably wish you had an AT (rear suspension) rather than a CT.

Have you looked at Recumpence's "letting the cat out of the bag" thread? That might be something to consider for your build. The 20" Magic Pie is tempting for sure, but it takes so many volts for any speed it might not be practical. I got to tell you, the Nuvinci sucks the watts. It's nice not having to shift, but the performance suffers for sure.

I really like how Li-ghtcycle set his up and there should be room behind the seat on the Bike E to put one of those Golden Motors.

I will echo what someone said before me about it taking serious watts to climb serious hills even through a mid-drive.

I tend to disagree with the stability at higher speeds issue others have mentioned though. I actually find the Bike E to be more pleasant above 25 than in the 15-20 mph range. At 30 it seems to just cruise. I do have the extended wheel base model though and that may help high speed stability though.

I look forward to seeing what you do!

Interesting.

I think I want to avoid drivetrain elements that are lossy. The Nuvinci seems to be in that category.

When I rode the bike today the hub would only shift into two of its three gears. Perhaps the cable needs adjustment.

It would be nice to avoid hacking the bike much in case I decide to upgrade to a better frame. I do wonder about having some suspension.

How do you take this bike anywhere on a vehicle? I used the truckbed to bring it home, but need a better way to carry it. Not sure it will fit on my car racks. The wheelbase is pretty long.

The manual mentions CT and AT models, and this one is definitely not the AT so does that mean it is the CT model?

Yes, an AT is the one with rear suspension, CT is no suspension. If you are on Facebook, please join the Bike E group linked in my sig.

OK, joined the group there. I do FB occasionally.

It should be a nice project Alan. I've always wanted to see how big a pack could hang under an EBikeE. Different input from 2 people about high speed handling is interesting, and must have to do with different trail on different models.

My recent recumbent results with quite slack head tube angle and different size wheels shows that you need a lot more trail than on more common bikes with steep head tube angles. The bike I first road tested today has a head tube at 55° (from horizontal, 35°from vertical), and with a 16" bike wheel it has a 5" trail. The bike is docile and well mannered at 10mph and tracks like on a rail at the 40-45mph I had it up to today, so I can't wait to get the recumbent seat done and ergonomic handlebars done. ES distance records are about to be obliterated, especially since I built the bike to easily fit and haul 7-10kwh of batts, and I have more than enough batts to fill it up.

John

veloman said:

A BikeE isn't very aerodynamic, there are many better options. It might be a tad better than a mtb position, but not by much if at all.

Click to expand...

Thanks for your comments.

From what I've read a non-faired recumbent does have a notable edge over a racing bike, and a racing bike has a notable edge over a mountain bike. So I would expect some improvement. Based on frontal area it would seem that the main difference is the legs rotating 90 degrees from about the worst cross section to about the best for the legs and feet.

But you may be right, the difference may be not too large. I would hope it might be 10-20% but who knows. At least it is not likely worse.

I read that a good rider on a recumbent beat four probably better riders in a peleton. So perhaps a recumbent is comparable to the efficiency of a peleton.

In the Mega Enduro riders are allowed 20 watt hours of battery per mile. And there is a lot of climbing. Seems a bit marginal for a mountain bike. Any improvement may be a big help.

If I start with a reversible setup, so I can return the bikeE to stock if I decide to do something else, I would think a hubmotor would be best.

The front wheel has a steel fork as I understand it (need to check), but not a lot of traction and is only 16". So a hubmotor in a 16" wheel would easily go there. This would allow the full 21 pedal speeds.

The rear wheel is 20" and has the 3 speed hub and 7 speed cog set. So one easy is to put a 20" hubmotor with 7 speed freewheel in the rear. This would give only 7 pedal speeds. The front chainring is about 46 but I saw someone put a 52 on there.

For the motor the two interesting choices are the Pie II or a large geared hubmotor. The Pie with a spokeless wheel is interesting.

I need to verify the axle width on the bikeE. Hopefully it is 135mm.

There is a thread on the 20" Pie factory mounted in an aluminum (non spoked) wheel:

http://endless-sphere.com/forums/viewtopic.php?f=6&t=35060

Looks like 20S 3.8V lipo gives 27 mph. So 18S would be 25 mph.

But is it still available? Where??

My experience with a mid-drive and hub upright are:

1) the mid-drive of course climbs like a goat. It does it with amazingly few watts. It will carry a tremendous load.
2) my 2810 hub-motor MTB on 18s will also climb like a goat but it wants to be going over 10 mph to do so. 15 is even better. 20 is awesome. If you are carrying a large load, it is going to take a lot of power. If you have and can sustain the power, it is faster and more fun.

Power required to climb hills is a function of grade and speed, no matter what the drive system is. My hub motor bike will climb a very steep hill as long as I maintain a high enough speed and I watch the power. It will not carry the load my mid-drive utility bike will because it would require too much power and would overheat if it had to climb very long. I'm sure you could build a hub motor that would, however. It would suck the power doing it though.

I have often thought about getting a recumbent similar to the one you show. If I did, I would put a hub motor on it that would get me to 25 mph at 18s. I have some 20% grades but they are short. I have some longer runs of 5-10% grades and I can do those at 20 mph for at least a mile or more without the motor or controller getting significantly warm. I like my mid-drive, but there are more parts and the drive train parts wear faster due to the fact that the extra torque is going through the entire drive train. It would be a daily driver and not a big cargo carrier.

Anyway, those are my thoughts.

The front fork is indeed steel, but be aware that one of the issues you will have to deal with in a front hub application is finding or making a 36h 16" wheel. A great option would be to get the Hammerschmidt that mdd007 has for sale and put the Magic Pie in the back. That would be too cool for school! 8) It would be a bit spendy though.

http://endless-sphere.com/forums/viewtopic.php?f=31&t=35156&p=514205&hilit=hammerschmidt#p514205

Thanks for the comments.

Good point on the spoke count in the front wheel. I do recall seeing that somewhere before but had not thought about it recently.

I notice that Golden Motor Canada has a 16" 1000W scooter wheel. May be too wide for the front fork.

The 20" Magic Pie II external controller seems like a good fit for 18S 25 mph. Or perhaps a Mac or BMC gearmotor. I wonder which would be more efficient for a 100 mile ride at 20 mph with hills (like the Mega Enduro)?

An interesting battery mount might be some of that PVC downspout material. Strap over or under the frame beam. Very clean looking. Could have a pair of 18S 1KW sections, use as needed depending on trip length.

In my mind the ideal motor for that is a Crystalyte 404 (16") front, but you can't find those anymore. You could also use a Crystalyte 209 which is a lower powered small direct drive motor set up for folders - 79mm dropout width. It is quite high RPM and would work nicely in a 16" wheel, but it wouldn't be very fast, topping out around 20mph I imagine. That would give you nice balance with batteries on the back. Otherwise it would be tail-heavy with a rear motor, unless a small geared type, with tendencies to wheelie, especially if you are tall and have the seat right back. Otherwise a mid-drive would be better like a cylone or similar. I've got a 404 on a 16" front wheel on a Rebike recumbent and it is very fast and quiet.

Thanks for your comments.

I didn't expect there was much wheelie potential in a recumbent. Interesting to know. I'm a bit under six feet tall so the seat is not all the way back.

I expect that I'll set up the back for a Topeak trunk bag. Perhaps I can mount the top part of the rack right on the rail. I won't use that for batteries, that's reserved for important stuff like my lunch.

I'll probably put batteries along the main beam as far forward as I can, if the motor is in the rear hub.

StudEbiker wrote:

but be aware that one of the issues you will have to deal with in a front hub application is finding or making a 36h 16" wheel.

Click to expand...

I don't think it should be a problem. A few years ago I puchased a Bafang from JohnRobHolmes and he laced it into a nice Sun Rhyno Lite double wall 16" rim with 36 holes. Prior to that I decided to relace one of my BD36's into a 16" wheel and purchased a basic single wall 36 hole rim directly from Wilderness Energy.

Options at 16 inches, good to know.

My wife rode a Bike-e with a front C/L brushed motor for years and really enjoyed it. I laced the 16" front hub and it is still working 10 years later. We now ride trikes cause of too many E/R visits on 2 wheels but the Bke-e is still used by grandkids. Reliable and fairly good handling. Front wheel drive works well at 36 volts and at 54 volts it really flies. You don't notice the brushed ineffeciency much in a small wheel like this.
otherDoc
edit: I did have to bend the front steel fork a bit to fit the motor but probably a 9C or Magicpie would fit without bending.

Alan B said:

veloman said:

A BikeE isn't very aerodynamic, there are many better options. It might be a tad better than a mtb position, but not by much if at all.

Click to expand...

Thanks for your comments.

From what I've read a non-faired recumbent does have a notable edge over a racing bike, and a racing bike has a notable edge over a mountain bike. So I would expect some improvement. Based on frontal area it would seem that the main difference is the legs rotating 90 degrees from about the worst cross section to about the best for the legs and feet.

But you may be right, the difference may be not too large. I would hope it might be 10-20% but who knows. At least it is not likely worse.

I read that a good rider on a recumbent beat four probably better riders in a peleton. So perhaps a recumbent is comparable to the efficiency of a peleton.

Click to expand...

not even close to a peleton...

there's big difference between a lowracer and a comfort cruiser.
I think the bikeE is probably worse than a road bike with aero bars.

so far, non-faired recumbents have not been able to beat the upright (no aero bar) in the hour.

I was referring to memory of reading the following from the wikipedia article on recumbent bicycles:

On 7 July 1933, at a Paris velodrome, Faure rode a Velocar 45.055 km (27.996 mi) in one hour, beating an almost 20-year-old hour record held by Oscar Egg,
...
In 2003, Rob English took on and beat the UK 4-man pursuit champions VC St Raphael in a 4000 m challenge race at Reading, beating them by a margin of 4 min 55.5 s to 5 min 6.87 s - and dropping one of the St Raphael riders along the way.

Click to expand...

Of course I don't know all the details of these, and the EbikeE isn't the same as these racing recumbents, but my expectation is only that an EbikeE is more aerodynamic than a Mountain Bike. I have read that people have ridden EbikeE's in 100 mile rides, how many folks ride mountain bikes in 100 mile rides?