Building a recumbent bike

Kurt

10 kW
Joined
Apr 21, 2008
Messages
962
Location
South Australia
At first I wanted a tadpole recumbent but after thinking it over more I think a 2 wheeled recumbent would be more practical. Being a machinist/fabricator by trade I guess I should build it my self.I am comfortable with the build side of the project but were I need some help is the bicycle design side of things.I also dont want to spend a lot of money on the project so most of the components would be used from other bikes.When its built i would like to transfer by 5304 onto the back.

I was thinking of buying this dvd to get some ideas from .
http://cgi.ebay.com/Build-the-RB-LWB-Recumbent-Bicycle-Bike-DVD-Video_W0QQitemZ330281204216QQihZ014QQcategoryZ62130QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

kurt.



This is the style I like.
2971760346_2566e53cf4.jpg
 
Front fork looks a little weak for Ebike so might need to beef that up.

That also looks like a bad pedaling position, you would neither be over the top of the pedals nor have the pedals out in front. Instead, the pedals are forward and down where there is no way to put any force behind the pedaling motion.

Since it is supposed to be an ebike, the pedaling situation is probably a moot point.
 
Here's a thread on the Long Wheelbase recumbent I built a couple of years ago. It's still pretty much the same but I built a new battery box back in March and went to 3 Milwaukee V28 tool batteries in parallel. I now have over 2000 miles on it and it is still going strong.

http://endless-sphere.com/forums/viewtopic.php?f=6&t=141

Here's a direct link to the pdf I wrote on how I built it:

http://endless-sphere.com/forums/download/file.php?id=455
 
Thanks guys, Its comfort and wind drag that I like most about a recumbent design. I have ridden a tadpole just up the street and back. I was surprised at how stiff the steering was for sharp low speed turns.The safety aspect doesn't bother me that much with the tadpole. As I think they draw attention and stand out out more on on the road. The negative side I see is how wide they are would make riding the foot paths a little harder.

Being able to ride a particular Design of recumbent before you build it I think is always the best. As some of the quirky looking design's are probably better to ride than they look.

I think I will do some more research.
Kurt.
 
What you have pictured is an Easy Racers Tour Easy clone. It looks to be fairly well done except for the choice of fork, way too light duty. I rode a Tour Easy for 11 years, just recently sold it and went to a Sun EZ3 AX delta trike with a WE 400w (BL36) pedal-first hub and solar panels to boost range and recharge batts. My other ride is a HPVelotechnik Scorpion Trike, pedaled over 4000 miles/year. I am a FROG - a fat retired old guy, and wouldn't jam a df seat up my clacker even if paid. We trike riders have an answer to those that say we are too low, it being, "Do you have trouble seeing the lines on the pavement? They are even lower than I am!" That usually shuts the dumbwadds up fast. I went to an electrified trike because of stability problems caused by heavy solar panels on a single wheel trailer behind the TE, plus, it was a long cable run from the trailer to the hub - over 8 feet! Having sla 36v 12ah batts atop a 700c rear wheel made for a shorter cable run but worse stability problems than an overloaded trailer.

The best thing about a TE made in cromo is the compliance built into the frame, which is taken away when running a aluminum frame, and regained when the frame is in Ti alloys but still as light as the aluminum. LWB (long wheel based) recumbents are treasured for stablilty at speed (as long as not overloaded with solar and batts), and they can be much faster than diamond frame bikes due to aerodynamic advantages, which is why recumbents are banned from most races - you'll never see one in the TdF or similar race. The pedaling position is remarkably efficient. Most people do not realize that you are limited in the amount of power you can produce when standing. Using myself as an example, I weigh 240#, which means the most weight I can apply to a pedal while standing on it is 240#. On a leg press I have done over 3 sets of 10 reps with 700# ( yeah, it was a few years ago, I was 55 then, 60 now). Divide 700/2 - way more than 240! Most pro riders you see stay seated on df bikes because you can produce more power over a longer time seated using cleats or toe straps to attach your feet to the pedals. They stand for a burst, but sit down asap. Of course, on a 'bent, standing on the pedals is impossible.

Just a few current records held by pedal powered recumbents. 1 hr. unfaired - 29 miles. 1 hr. faired - 53 + miles (on a 70# faired Varna, at the Nissan test track in Az, warm!!), top speed - 83 mph, again a 70# Varna using a 5 mile run in to a 200 yd. speed trap, done twice into wind, with wind. These records are held by cream of the crop recumbent riders, the 1 hr. faired record was set by the owner of Easy Racers, "Fast" Freddy Markham, a former US Olympic Team rider - at over 50 years of age!

It shouldn't be difficult to pick up a lovingly used steel TE for not much more than you would pay for all the parts you would need to buy. Sure, build your own if you want an adventure, or buy a used one - check out BROL, BentRiderOnline for classifieds. Motorize it and have a ball!
 
Kurt,

I've built quite a few LWB TE clones, and somewhere I have Gardner's original planset. The build is pretty straight forward. The most often made mistake when building TE clones is the steering geometry. Builders unknowingly use the donor's original tube angles, which nearly always results in the incorrect steer tube angle. Then they are forced to use excessive tiller for proper reach, which sadly corrupts low speed handling and makes the bike feel strangely awkward. The fix is easy, but must be done early in the build. The laden (motorless) weight distribution usually ends-up around 60r/40f, and with rear mounted motor the optimum battery placement will be just forward of the seat and slightly below the top tube - right where the small diagonal is (which is of no use anyway, and should be omitted during the build). Contrary to previous comments, and assuming 'rear' mounted motor, a quality chromoly road fork will be more than adaquate. Drop me a PM anytime, and i'll be happy to exchange.
 
Papa,

Very nice bikes!

How about some higher-resolution closeups of joints/welds and such.
I'm interested in your construction methods. Brazed or GTAW (TIG)
welded? Welding/brazing equipment used, jigs and fixtures? Source of
BB shell, tubes, forks, dropouts, etc?
 
Kurt, do you live in a hilly area? If not the following is irrelevant:
Here's my experience. I visited a company in Cambridgeshire, England who, for £25 would allow you 1.5 hours trying out as many bikes (mostly recumbents) that you liked. I actually got 4.5 hours worth of trials and must have tried about 20 bikes. I expressed intrerest in a tadpole trike but was told that 2 wheels was much better as there was less drag than with 3 wheels. I came away wanting to buy a 2-wheeled recumbent. I should point out that Cambridgeshire is totally flat and where I live is very hilly. I went home and fortunately I tried the same 2 wheel recumbent that I had tried in Cambridgeshire by hiring from a nearby cycle centre. I found that I was totally unable to pedal uphills; the effort required from my untrained muscles was much too great. I then had the chance to try out various Trice tadpole recumbents at the factory in Falmouth. They were great! You can stop and rest when going up very steep hills. You may be very fit and young, so this wouldn't apply to you, but, even if you electrify your bike, there will be times (perhaps) when you have to pedal uphills with a dead battery. On 2 wheels you have a balance/speed problem. Try pedalling a 2 wheel recumbent up a steep hill before you buy! Hope this helps
 
http://www.gaerlan.com/bikeparts/frame/tubing/tubing.html
http://store.valueweb.com/servlet/poweron/Categories?category=FRAME+BUILDING+PARTS
http://www.henryjames.com
http://www.novacycles.com
http://www.framebuilding.com (UK)
 
All I can say, is that be careful building a recumbent bike.
It can be addictive!
I have built 2 trikes for myself, 1 SWB 'bent, two trikes for my daughter and a friend, and I currently building a fully suspended dual 20" SWB bent, and all in the last year!
DSC_0160800x600.jpg
 
I began riding 2 wheel recumbents in 1999. Switched from riding a wedgie. One ride was all it took. I will <never> subject myself to the torture of upright riding again, and the numb hands & wrists, stiff neck, sore back, and mutilated nether regions that go along with it.

Seems to me a greater variety of designs were available then than now. As other posters have noted, each style has a completely different feel to it. Conclusions you may draw after riding one style may be completely different from another. Ride as many as possible.

The same is true with trikes. Frame material---aluminum (aluminium?) steel, graphite---all produce a different ride. Steering can be light or heavy, quick or slow, depending on the linkage used. Seat back angle can be fixed or adjustable. Rear wheel can be rigid or suspended. Turning radius can be big, or bigger! :wink:

In 2004 I switched to a trike and seldom ride 2 wheels anymore. Due to the low height I always use a flag. Watching drivers' eyes, I've seen the flag make a difference. They see the flag first and follow it down to the trike. However, drivers that pass from behind seem to allow much more room than when I was on 2 wheels. Almost like they think that having 3 wheels makes you a legitimate vehicle, whereas with 2 wheels you're only a bike.

I've never encountered a problem with space on a bike or foot path, however most paths around here are old rail lines so they're seldom narrower than 6-8 feet. The front wheels are too wide to fit through most motel room doorways. The answer is to pick it up, flip it onto a side so I'm standing inside the seat, and take it through the door that way.

Theoretically, 3 wheels should be slower than 2, and this seems to be true. However, it didn't seem all that severe. I don't have hard data to back it up, but my impression is that a route where I might average 15 mph on 2 wheels would average 14 mph on 3 wheels. Frankly, whatever difference there was ceased to be important after 1 or 2 rides.

Biggest differences are 1) You need to watch 3 wheel tracks instead of only 1, and 2) You will notice road camber.

Fellow I ride with has a Tour Easy similar to your picture and has many 1000's of miles on it. Stuck a fairing on it. Bar none, he is the fastest recumbent downhill, despite others being more reclined. Also better than average going uphill, where recumbents typically aren't as quick as uprights. I would think it to be an excellent choice to electrify. IMHO, I'd put the motor on the rear. With recumbents, you can't shift weight or stand to absorb bumps, so anything that helps the front wheel to get through or over a bump is good, especially with a small diameter wheel.

MT
 
If you build a long wheel base recumbent, you will want the motor driving the rear wheel. I think a long wheel base lends itself well to a setup with the motor driving the chain directly.
 
Thanks for all the photos and great advise. The main reason behind building one myself was I need something to tinker with as a retired fitter-turner in the dairy food industry I spent a lot of time welding all manner of SS pipe work and i need a fix again :lol: .I don't like how all my gear is now gathering dust in the garage.I think I will start by building the bike I first posted the picture of .I will run my 5304 hub on the rear and 36/20ah headway pack in the frame.Most likely all styles of recumbent s will start breading in my garage after the first as they have with others.

I was at a large shopping complex the other day and they had a rubbish skip full of wheel chairs they must of been upgrading there complementary chairs.I was thinking of taking some of the wheels for a tadpole trike but wasn't sure if they would be any good and then my wife started nagging something in my ear about collecting junk :lol:

After another 20km ride today on my mtn bike frame it just didn't feel as fun as it could be if I was sitting down.It has to be better then leaning down onto the handle bars with neck bent up arched over trying to see where I was going .I find with the 5304 I don't need great uphill peddling ability but on the flat sections and starting off I would like to be able to assist slightly. I find doing so keeps the wh/km down to around 10-15.

Fast speeds are not a huge priority ether. I tyred my mtn bike this afternoon on 72volts 48a controller. It performed like a slow motorbike and probably would have hit 70kmh. Wearing shorts and a t shirt didn't give me a lot of confidence so I pulled up at around 60kmh.I think a max speed of around 40kmh for my ebikes is all I want.

kurt.
 
Get those wheelchair wheels! Those hubs are ideal for front wheels on a tadpole trike!
12mm axle, and already setup as a stub axle, go for it.
 
Papa said:
The most often made mistake when building TE clones is the steering geometry. Builders unknowingly use the donor's original tube angles, which nearly always results in the incorrect steer tube angle.

A friend of mine built two LWB recumbent bikes and he said the exact same thing about steering angle.

When he test rode my factory recumbent bike the very first thing he did was take his hands off the steering for a second and said the angle felt perfect, yet the difference was only a few degree's.

Couple folks here mentioned placing the motor in the rear wheel, mine is mounted in front and after 5,000 KM's the only issue is climbing gravel hills with bumps, it has a tendancy to bounce the front wheel up & down as it grabs traction erraticly. All that is needed is to start pedaling of course and you have all-wheel-drive.

These bikes are perfectly suited to convert to ebikes for many reasons, but mounting batteries is the easiest of all bikes. Under seat pannier racks and bags are readily availlable from many makers and are almost idealy located with room to spare.

Wow, some great looking home made bikes & trikes on here, and thanks for the plans.
 
Papa said:
The most often made mistake when building TE clones is the steering geometry. Builders unknowingly use the donor's original tube angles, which nearly always results in the incorrect steer tube angle.
recumbent said:
A friend of mine built two LWB recumbent bikes and he said the exact same thing about steering angle.

When he test rode my factory recumbent bike the very first thing he did was take his hands off the steering for a second and said the angle felt perfect, yet the difference was only a few degree's.
The main factors effecting handling on LWB 'bents is wheelbase, CoM location, 'trail' and 'tiller'. The steer or head tube angle (and physical head tube location) is usually determined by ergonomics. Easy Racer's Tour Easy, has a head tube angle of 59 degrees, while the Fold Rush is 65 degrees. Yet everyone who has ridden both 'bents say handling is identical.

Short of troubleshooting (for frame alignment issues and such), I'm not sure that riding hands-free reveals much of anything about handling. On most of my LWB builds, I frequently eliminate 'trail' entirely, which effectively eliminates hands-free riding anyway. And considering my bitterness towards hands-free, cell-phone-using-cager-drivers, I see little reason to add to, or promote the practice.

recumbent said:
Couple folks here mentioned placing the motor in the rear wheel, mine is mounted in front
Have you ever experienced high speed oscillations - mild or otherwise?

Many here, have, and successfully use hub motors. It's an easy 'bolt-on' fix for an otherwise complex problem. But I prefer to avoid them, primarily because of the way they alter the CoM, and add mass to the wheels.
 
Papa said:
On most of my LWB builds, I frequently eliminate 'trail' entirely, which effectively eliminates hands-free riding anyway. Have you ever experienced high speed oscillations - mild or otherwise? .

No oscillations, tracks true and steady, i'll try and measure the "trail" angle with a string and scale from my mathematical set. My bike has 70" wheel base, it's a Canadian production made version of the "Tour Easy Racer" design, modified with heavier rear triangle and drop-out plates (literally). Heavy duty designed rear drop-outs, very solid & clever.
This bike screams to be modified for ebike use, even the 48 volt battery pack fits snugly behind the seat base.

As for hands free riding, I do not do that, or think i can with this bike, it was a friend that did it.

The beauty of these bikes above all is the supreme comfort, even after a couple hours riding, no soreness.
And when we go to the band shell for out door events, you always have the best seat in the house.
Should have bought this bike 20 years ago, oh well, live and learn.
 
recumbent said:
My bike has 70" wheel base, it's a Canadian production made version of the "Tour Easy Racer" design,
The only Canadian production LWB i'm aware of is the Recumboni - http://www.cambiecycles.com/frameworks.html
 
I like the look of the SWB racers, and perusing the net came across this for a build.

xr25ss.jpg

xr2-1.jpg


Its called the Ground Hugger XR2
The frame cost less than $300 to build!!
If you watch the video, the steering placement sucks, I think an underseat would be more comfortable.
 
Definately some cool lookin designs on the market to choose from.

The steering is too close to the rider, and seats too low on the carbon/fibreglass model "etard" posted for us. Easy to correct, but curious to know how it handles.

The LWB (Recumboni from "Frameworks") "Papa" posted above the fancy fiberglass model is indeed my bike, and the handling is perfected, as far as i can tell.
It's an ideal platform to easily convert to an ebike as i mentioned before, and take huge loads over 300lbs, including me and the bike of course.

Surprisingly they make bike carriers for these long & lean bikes. http://www.swagman.net make wonderful easy to load carrier for your car, which i own. You can also carry regular bikes at the same time if you want, for only $160 canadian.
 
There has been a fair bit of discussion on BROL about this design. Apparently the universal joint in the steering is less than ideal.
I notice that there is also a mid hub. These have also proved to be less than satisfactory in the power transfer department.
There plenty of good designs out there, and the TE Clone is very popular.
I'm also hearing very good reports on the TW bents. They are cheap enough that if you are not that confident building your own, then will end up with a very good bike.
 
My first recumbent build was influenced by that Ground Hugger XR2. The steering was a nightmare and I am surprised I didn't get hurt. Just use two head tubes and some ball joints if you want the wheel base that long.

Building a rideable recumbent is pretty easy if you have a couple of donor bikes and a torch. With one bike you might run into problems if you accidentally break some part or screw something up, which seems inevitable on the first go around.

SWB is ridiculously easy-- just take a donor frame and cut the downtube near the steering tube, cut off the other tubes, and weld the tube+pedals onto the steering tube of a BMX bike or Warlmart princess bike. Add a guide for the chain to keep it from rubbing on the front wheel (old roller blade wheel, pulley, piece of delrin or teflon, whatever) and another length of chain. Extend the steering tube upwards by about a foot using an extension or by welding one on. Bolt a seat to the top tube of the BMX bike (old exercise equipment seats work). Bolt a seat back to the original seat post (I like office chairs). Voila, you are done.
 
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