Hi-Efficiency Recumbent Commuter Conversion

[jkbrigman]

"I realized this week that this bike is a very good clone of the Bachetta Giro 20 - in fact, if you look closely at the two, you can see enough similarities to wonder if it's only the minor differences in frame construction that differentiate between the two."

Sorry but your bike has some very significant differences. The front wheel is much further back. This makes the wheelbase too short, and puts too much load on that small front wheel. If you get a chance, ride a modern medium wheelbase bike like the Bachetta, RANS, Volae, etc. You will be amazed at the difference.

Warren, the numbers do not support your contention. On the Bachetta Giro 20, the wheelbase is 47", per:
http://www.bacchettabikes.com/bikes/tou ... es/giro-20
The precisely measured wheelbase, axle-to-axle, on my Bachetta clone is 46.5".

Below is a photo of the Bachetta Giro 20 I pulled off Google:

My bike is a clone of this bike.

bachetta giro 20.jpeg (9.76 KiB) Viewed 413 times

The image of the bike from the Bachetta website even shows the same brand of brakes, wheels and tires. The only differences I can see are in the seat and seat stays, driveline components and the handlebar assembly and the fact that the boom on my bike is adjustable, while on the Bachetta, it is not. My bike is over 5 years old and I'm comparing it to an image off the Bachetta website of a 2012 Giro 20. (In the image I have in this posting, that bike has disc brakes. The stock Giro 20 has V-brakes that are identical to mine.)

I do not mean to diminish the quality and value of the Bachetta Giro 20, which is off topic of this forum post. This thread is, if nothing, a tribute to the comfort and capability of the design. The most important point I'm making in this thread that my research has (sadly) revealed: a SWB recumbent with a 20" front wheel is too dangerous to mod into an ebike that runs at 30mph. I do not recommend this be done by anyone else in these forums and I plan to remove the components from this bicycle and put them on something else. I am in mourning about this and trying to get used to the idea of giving up this bike for commuting, because this recumbent is a thing of beauty: I biked 31 miles on it in jeans and street clothes in complete and absolute comfort. But I just can't recommend anyone else do this ebike conversion for safety reasons.

[jkbrigman]

only thing I can think of atm is fabrication. Perhaps a metal shop could build you something under there with padding and a nice secure door, welded to the frame or something to keep it from swinging. No where to really hang a pack under there without that problem. Ill have to grind my brain on this one. Watch for sharp corners! your calves with thank you when you come off the pedals for a stop or something.

K, you're right on that. The bike has bosses on the rear seat stays for something. I think you can buy pannier mounts that'll fit those bosses, but I would have to remove the rear rack to use them. More in a moment - I have news to report...

[jkbrigman]

I've got some exciting news to report: On a street recumbent with high pressure tires, you can go 30 miles, at speeds between 20 and 30mph, on 18S3P LiPo and still have plenty of juice left in the pack. On Friday, 30 March 2012, I did exactly that, completing a 62.5 mile commute with an 18S3P LiPo pack and a bulk charge halfway through.

Pannier contains the work laptop and a change of clothes.

loaded.jpg (100.42 KiB) Viewed 425 times

This is an unstable bike, but the pannier improved stability perceptibly. Note to self: try putting the batteries in a pannier on the other side to see what that feels like.

I made it the first 31 miles in about 1hr, 45 minutes. I had a chain malfunction (it got jammed between the freewheel and the derailleur hanger) so I spent 20 minutes fixing that, but arrived at work only slightly delayed and none the worse for wear. Here's the view of the bike in the bike rack at work, after completing the 31 mile inbound leg of the trip:

In the bike rack at work, battery tote is removed and charging. Didn't lock it down. If you can steal it without batteries, more power to you....

at work.jpg (90.63 KiB) Viewed 425 times

On the trip back, I stopped at the convenience store from earlier photos in this thread and snapped another photo showing the sign with the current gas price as-of 30 March 2012. Compared to that earlier photo, the price digits on the LED display have flipped position: gas that was $3.79 only days ago is now $3.97 today. I'm not saying everyone needs to abandon their cars and ride with me, but I am saying that I sure enjoy not buying this gas today.

Shocked at the price rise. Got to redo my ROI for $4/gallon gasoline.

higher gas.jpg (135.59 KiB) Viewed 425 times

Final results of the ride:

Total miles showing on the CA

miles.jpg (34.72 KiB) Viewed 426 times

Speeds:

Not bad for 62 miles...

speeds.jpg (35.48 KiB) Viewed 425 times

Final Efficiency Numbers:

I pedaled about 90% of the time to get this number....

efficiency.jpg (33.83 KiB) Viewed 425 times

I have already been asked: "Could I make the trip on this bike every day?" Well, I have to admit, the answer is NO. The average speed I made this trip in, about 20mph, is too slow. It takes too long to cover the distance. The bike is not as stable as I'd like (fixable) and the front wheel is too far back (not fixable) making me worried I'll hit something, cantilever over the bike and do a face plant at 30mph.

What next? I don't know. I absolutely hate to give up the recumbent - the comfort is impressive. I made this commute in street clothes with no chafing or discomfort whatsoever. That's the incredible benefit of a recumbent. But for an ebike to work on this route, I need just a little more average speed (closer to 30mph) and probably a suspended bike to manage that kind of speed safely.

But I am happy to finish this thread with the following conclusions:

1) An 18S3P LiPo provides enough power to travel 30 miles in moderately hilly terrain at an average speed of 20 miles per hour.
2) The experience of commuting to work on an ebike is amazing. Although the trip took roughly 2 hours each way, the recumbent was amazingly comfortable, even while pedaling in jeans!
3) Gasoline is seeing rapid rises in price, which make the economics of an ebike even more favorable. I "saved" over $10 on this experimental trip against the cost of the bike and parts.
4) The knowledge and support of the members of Endless Sphere forums were crucial in making this possible! I doubt I could have succeeded so much the first time out without the help of all you great forum buddies! Special thanks go out to Kin, veloman, cell_man, methods, dogman, neptronix, Kinni420, Alan B, DrkAngel, all who have responded in this thread and all who have patiently answered my endless questions!

No matter how you see it, this ebike has been a success, meeting the design criteria of the mission in every way.

[jkbrigman]

Four LiPo 6S bricks, in series, fit nicely in the "battery tote" shown in prior postings. Thought I'd try an experiment and see the "theoretical maximum speed" the wheel can turn on 24S, and also to see if the CA and 25A 6 FET IRFB controller can handle the juice. Here's the image of the CA while I'm letting the rear wheel spin off the ground on the kickstand:

CA showing 4 LiPo 6S bricks in series, 91VDC at this point.
40.9MPH maximum theoretical speed at this state of charge.
Translates to a flat road estimate of about 35MPH.

24S.jpg (137.38 KiB) Viewed 413 times

Keep in mind that my LiPo hasn't been charged from the last use, the giant commute posted above. I wanted the voltage sag to protect the controller and CA. Results look promising! I know what my next test is gonna be!

Update Sunday Night: Took a short ride on 24S LiPo with the 9C 2810 and it was incredible. Big, big boost in performance and responsiveness! Nice push of the high-end speed from 31.7 to 35.6MPH. It was a rush, even if it was dangerous. Wonderful thing is that the Methods 6FET Infineon 25A controller can handle the voltage - at least the 91V the 24S of semi-discharged LiPo was producing at the time - I was afraid to go any closer to 100V, as that's well beyond the advertised rating of the controller.

Strange, strange observation, however: I was seeing usable regen and LOWER speeds with the higher voltage battery! The CA indicated -2% regen at only 14mph. I have no explanation for this.....

JKB

[Kinni420]

Hey James...sorry I havent gotten back to your question. The only time Ive seen heat was climbing that single-track last weekend. Id call it "warm" about 50C or so on all parts.

I fell yesterday and screwed myself pretty bad. probably a couple cracked ribs. pushing it for film doh. Ill survive...bikes fine...pretty low speed fall, just landed wrong. loving to see that kind of range!

aren't you running methods 40A controller? or do you have it set down to 25A?

supposed to rain here tomorrow...not looking forward to the commute in pain and wetness. Ill try to take some video lol.

p.s. not gonna post me crashing on vid lol.

[veloman]

This is what you need for 30mph commuting.
Oh, and thanks for the thanks! Glad I could help!

[Recumbent Bicycle Source]

There are a lot of generalizations here about recumbent bicycles based on a single bicycle experience (The one you own). There are a whole lot of flavors of recumbent bicycles. So the generalizations are not valid. I ride a SWB and have no difficulty looking behind me any more than when I'm on my mountain bike. Heel strike is only a problem on some models. Changing the front fork and steering (bars) can have dramatic effects on handling. So just like an upright or road bike or trike or ??? it's all about finding the bicycle that fits you and your riding style.

The advantage of crank forward semi recumbent is not efficiency it's rider position. The crank forward allows the rider to place both feet flat on the ground while still in the saddle. I find them more difficult to climb vs a diamond frame mountain bike, but very pleasant on the flats as long as there is not a lot of wind. I've ridden Day 6, Townie/Pure and they would make nice electric conversions, but are not as comfortable as a nicely fit recumbent. Back support makes riding much more enjoyable and relieves the pressure on the wrist.

Ultimately for comfort a tadpole trike with a headrest can't be beat, but it's scary enough in traffic on a SWB. People haven't seen a lot of them and tend to steer towards you out of curiosity.

Try riding some different bikes and find the one you like... it looks like you've got yours as dialed in as it's going to get. Might I suggest however a head/neck rest to improve the commuting experience. And a Bullhorn to shout at the idiots that are so glued to their cell phones they drive you off the side of the road without even realizing it.

Unfortunately there are not a lot of recumbent dealers in the USA and even fewer manufacturers. To compare a Taiwanese knock off to what is manufactured in Europe is to compare store brand cola to coke. It's just not the same stuff.

[jkbrigman]

This is what you need for 30mph commuting.
Oh, and thanks for the thanks! Glad I could help!

veloman - that is one of the sexiest machines I think I've ever seen. Add suspension to it and you'll cause me to drool all over my keyboard.
As for using that as an ebike, you are dead-right about that. And I do truly appreciate your input on this project - cool headed, experienced, just the kind of information I was looking for.

I don't want anyone to think I've "given up on a recumbent ebike", or that I think recumbents are bad for ebiking, or that I would compare my little korean klone to the almighty Bachetta as if they are the same bike. They might be the same general shape, but what I was using the Bachetta comparison for was to estimate if I was over the weight capacity of my own bike, that's all.

In my fantasy world, I'd be able to come up with a suspended version of exactly the bike you've posted. It would be able to hit 40mph, cruise at 30mph, and I'd be able to make the 30 mile commute in 1 hr flat, same time it takes with the car. I'd forget all about gasoline and just enjoy the ride....

Wow....

[veloman]

Keep an eye on this for sale section:
http://www.bentrideronline.com/messageb ... ay.php?f=5

Optima makes a couple suspended recumbents, the Cougar looks like a decent wheelbase. Not cheap though.


There are some rear suspension recumbents, but can't think of any on there at the moment that have a longer wheelbase. I think rear suspension on a recumbent would be a no brainer, especially for electric.

[jkbrigman]

Keep an eye on this for sale section:
http://www.bentrideronline.com/messageb ... ay.php?f=5

There are some rear suspension recumbents, but can't think of any on there at the moment that have a longer wheelbase. I think rear suspension on a recumbent would be a no brainer, especially for electric.

Thank you, will do! I've not bought a "replacement bike" for the recumbent, although I do have my sights on an upright. I think I could be accused of stalling....

I've found these websites and fallen in love:
http://sites.google.com/site/recycledrecumbents/home
This guy takes "junk bikes" and turns them into awesome recumbents.
I'm reading carefully to learn. He's not showing anything suspended, but I think that's just a detail....

And the Good Doctor has the ultimate recumbent medicine:
http://www.elmtreedental.com/AR%20Recumbent%2005.html
He's kicking butt and taking names...this would be my ultimate choice for electrification!

JKB

[Alan B]

There is a recumbent dealer not far from me here in Alameda that has a good reputation for helping folks with recumbent selection. He charges for his time but applies it as a discount towards a purchase. Unfortunately high end recumbents are pretty expensive, but with help from an expert and some test rides perhaps the correct model can be chosen. Perhaps a dealer like this one can be located near you. Of course finding one that is electric friendly is important, choosing the right bike must take into account the modifications it will need for epower.

Exploring an upright with dual suspension is a reasonable thing to try. The recumbent reigns supreme for all day riding and long range efficiency, but for a 30 mile commute a fully suspended upright should be adequately comfortable. Years of motorcycle experience in traffic is directly applicable to an upright and staying safe is the top challenge for commuting.

Having one of each is really nice. I enjoy both my ebikes, recumbent and hard-tail so far. Soon the double suspended Cromotored 'Borg will also live.

Best of luck in your search,

[www.recumbents.com]

A 20" front wheel is fine. I'd suggest just adding a front suspension fork. You can get them at the Hostel Shoppe. It will make a world of difference in how the bike feels "at speed", and safety in general. Also, change to the fattest tires you can get on the bike. And yes I do have lots of experience going fast on a wide range of recumbent bicycles. Something else I noticed about your bike is that it seems to be forward biased. Can you move the seat back and shorten the boom?

-Other Warren.

[chvidgov.bc.ca]

I really think this bike would be much better with the batteries on both sides under the seat, attached to a mid rack. I do this on my LWB Sun EZ-Sport, and it is a very meaningful improvement.

[chvidgov.bc.ca]

.

[jkbrigman]

I think you repeated yourself...

[jkbrigman]

So wait...

I really think this bike would be much better with the batteries on both sides under the seat, attached to a mid rack, nice and low. I do this on my LWB Sun EZ-Sport, and it is a very meaningful improvement. As well as on my Rebike, a cheap CLWB 20/16. It feels way better than on the back rack.

OK, will do. Working on that battery situation. I think you will like what I come up with. About that Sun EZ-sport....

I just read through your bike list:

DevinciVancouver Front9CHybrid with DiskBrakes
Rebike 20"R/16"F Bent C404 Front 48V 20A Crystalyte Pedal First
CCM 26" Cruiser Nexus 7 C406Front 48V 35Amp Crystalyte Start Imm
Sun EZSport CX 26R/20F LWBBent C405 Front 48V 35Amp Crystalyte Start Imm
Giant Revive DX 20" Nexus 7 RearSusp with GearedBrushed Front 48V 800W ecrazy
Actionbent T1 trike with Rear9C BMSBatterySensorless 12MosfetUniversal
Toucan20 dogscooter GearedBrushed Front 48V 800W ecrazy

It reads like a "Who's Who" of electrified recumbent vehicles. Which one do you like the best?

Please Please tell me about that Sun EZSport CX? Does it ride comfortable, stable and efficiently??? What's your typical ebike ride with it and does it perform well? How's your Wh/mi?

[chvidgov.bc.ca]

I've got two others to add to the list now....Sun EZ1 Compact LWB recumbent 20/16 with mid-rack, and Bazooka Explorer steel folding bike 20" with Conhis front 1000W.

It's really hard to say which of my bikes is the favourite. It depends on the application. I really like the semi-recumbent Rebike, for general hacking around town with its big tractor seat, and the Giant Revive is a super comfortable urban ride as well, kind of scooterlike with a nice Nine-C on it. For mid-range comfort the small Sun EZ1 is excellent, with the mid-rack. In winter wet conditions here in Victoria, for urban commuting I often ride the big hybrid, with dual disk breaks, and the larger big Apple tires. Very safe in very wet conditions. For long range touring the long-wheelbase Sun Ez-Sport recumbent with the fairing is very good, also a dry ride. But ultimately, the trike rules. No question. It is AWESOME. You can load it up with gear and dual packs and go for the weekend, and it won't fall over. Cruises nicely with moderate pedalling in the high twenties. The folders are for the occasional trip to Arizona, for compact travel. I'm out of ideas, and I've pretty well got all the bikes I'll ever need so just riding these days, not building. The Dog-scooter is awesome, but it turned out to be illegal. I just ride it at night very occasionally. I've got a mix of rear and front hubbies, and generally like the fronts better, for the balance.
On the Suns, the mid-racks are very good for balance and handling, and leave the rear rack for gear. On the trike I've got the batteries down low, right under the seat, and that craft really feels planted. Since I'm so tall I've pretty well gone with apehangers on all the non-recumbent bikes, and extra long 400mm seatposts and stems on the smaller 20" bikes, so there was a lot of searching for those parts in bike recyclers around Victoria.

Too many ebikes - but I enjoy them all. I even enjoy my one non-motorized bike, a Raleigh twenty one-speed, with a full front fork replacement, new bottom bracket. and all alloy wheels, which just leaves the original frame and that's all. I guess I'm bike crazy.

The EZSport is a great bike - a nice strong chromolly frame, easy to electify, and pretty nice and standard parts on it. Again, with the mid-rack and the fairing, it is easy to carry two Ping packs right under the seat, and still have all your cargo capability. I've been averaging around 14 watt hours per mile on that one, which means you're good for around ninety miles on two 48V 15Ahr Pings, with a nice easy pedaling cadence. And the seat is very comfortable I've found - the same seat btw as is on the smaller EZ-1. If I had to choose between the EZ-Sport and the EZ1, I'd definitely go with the EZSport - it is a much better distance tourer, and can be found for not too much money - maybe 700 Cdn, in good condition. I got mine with the fairing for 700 which I thought was an excellent deal. I was surprised how dry the fairing keeps you in rain. The EZ-1 is perhaps a bit twitchy at speed and demands a lot more concentration - the EZSport is like floating on air. All of that steel, along with the seat, and BigApples makes for a totally cushy ride.

[Kirk]

You might be forced to go with a less expensive trike, like a Terra Trike to keep in budget but I found my Catrike Expedition to be just about the most efficient and quickest ways to get around. I use it a couple of times a month to commute 70 mile round trip thru Springfield IL and 108 mile round trip thru Peoria, IL. The traffic in both cities is pretty nuts but they see my trike just fine and give me plenty of room. I use Zippy 6s1p 8000mAh 30C packs in a 12s6p configuration, for a 48V 48 Ah battery, with a GM 48V 1000W motor laced into a DT/Swiss F630 DH rim. The cruising sweet spot on old Route 66 is 32.4 mph, 13.8 Wh/mile. I've thought about going to 72V 48 Ah but icecube and I kept running the numbers and 48 Volts is a bit more efficient. If you decide to change bikes, please keep recumbent trikes in mind. They look too low for traffic but people see them just fine.

[jkbrigman]

You might be forced to go with a less expensive trike, like a Terra Trike to keep in budget but I found my Catrike Expedition to be just about the most efficient and quickest ways to get around. I use it a couple of times a month to commute 70 mile round trip thru Springfield IL and 108 mile round trip thru Peoria, IL. The traffic in both cities is pretty nuts but they see my trike just fine and give me plenty of room. I use Zippy 6s1p 8000mAh 30C packs in a 12s6p configuration, for a 48V 48 Ah battery, with a GM 48V 1000W motor laced into a DT/Swiss F630 DH rim. The cruising sweet spot on old Route 66 is 32.4 mph, 13.8 Wh/mile. I've thought about going to 72V 48 Ah but icecube and I kept running the numbers and 48 Volts is a bit more efficient. If you decide to change bikes, please keep recumbent trikes in mind. They look too low for traffic but people see them just fine.

Kirk, thanks a ton for the data....your speed - Wh/mile number is incredible. I know that area (wife's family is from Mattoon, IL) and it's beautifully flat, but how much pedaling and how hard are you pedaling to get that number?

I've admired the simplicity of the low-end Terra Trikes and I've often looked at the low-end "Rover". It's an amazing value (sub-$1k) for what it is. Even the low-end one speed has front disc brakes! http://www.terratrike.com/rover.php I like the 8 speed enclosed hub/transmission (Shimano, but they don't say whether it's the Nexus or the Alfine), but it hampers being able to use a hub motor - I wish they put an 8 speed derailleur on their low-end trike instead of the enclosed hub. Roger wilco on the GM at 48V: You make me wonder if a mid-drive or could improve on those efficiency numbers.

You can add an external cassette to the Shimano Nexus hub using this:
http://www.ebay.com/itm/FH-1056-Shimano ... vi-content

You talk about it being a commute: do you carry anything to/from on the trike? Laptop, clothes, briefcase?

[jkbrigman]

You might be forced to go with a less expensive trike, like a Terra Trike to keep in budget but I found my Catrike Expedition to be just about the most efficient and quickest ways to get around. I use it a couple of times a month to commute 70 mile round trip thru Springfield IL and 108 mile round trip thru Peoria, IL. The traffic in both cities is pretty nuts but they see my trike just fine and give me plenty of room. I use Zippy 6s1p 8000mAh 30C packs in a 12s6p configuration, for a 48V 48 Ah battery, with a GM 48V 1000W motor laced into a DT/Swiss F630 DH rim. The cruising sweet spot on old Route 66 is 32.4 mph, 13.8 Wh/mile. I've thought about going to 72V 48 Ah but icecube and I kept running the numbers and 48 Volts is a bit more efficient. If you decide to change bikes, please keep recumbent trikes in mind. They look too low for traffic but people see them just fine.

Kirk, I thought your comments were so good I cross-posted them to my "what is an efficient e-bike?" discussion. Your efficiency at 32.4mph is extremely impressive...

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