Rec-liner long wheel base recumbent

This is my first Instructable so we'll see how it goes.

I want to document the construction of my recumbent bicycle, herein after referred to as the Rec-liner, or more probably just the bike.

The bike has a number of unique features that may be of interest to other bike builders including;
- under-seat, remote steering
- intermediate drive with an elliptical front chain ring
- mostly standard bicycle parts to make replacing and upgrading parts easy

I built this bike around 18 months ago, but as I did not have Instructables in mind at that time so there are no actual build photos. I have however pulled the bike apart a little to take some photos so hopefully this should make the following easy to understand.

Step 1 Materials

You should be able to build the complete bike using only two donor bikes but there are a number of specific requirements for each.

Donor bike 1 - Mountain bike with 26in wheels
Parts required:
- rear end (rear triangle, bottom bracket, cranks, derailers etc.)
- handlebars, handlebar stem, head tube, fork tube
- an indexed gear system is recommended

Donor bike 2 - Mountain bike with 20in wheels
Parts required:
- front end (handlebar stem, head tube, forks, wheel)
- bottom bracket, cranks

Both bikes would ideally have triple chain rings that are removable from the cranks.

Additional parts:
2.8m of 50mm x 25mm rectangular section steel tube (1.2mm thickness)
Plywood for seat
Foam rubber for seat
Scrap steel plate (3mm)
1m of 10mm threaded rod
2 x 10mm rod ends (female thread)
Plastic tubing (10mm inside diameter)

Tools:
Welder (I used 130A arc welder with satisfactory results)
Usual tools required for bike maintenance

Comments

[frankcox]

Great Job!

You should have won the contest.
One question , all the recumbents I have seen seem to be trikes, is it difficult to balance when you are not moving?

[Layout]

With your feet on the ground it's possibly more comfortable than a bicycle. It is also fairly easy to balance at low speed with a little practice and confidence.

[frankcox]

Thanks!

[mehpersonguy0]

Just wanted to be sure...what type of arc welding did you use? (Stick, MIG or TIG?)

[Layout]

I used a stick welder with passable results. That said, I have since purchased a MIG welder and would never go back.

[sayoian99]

ah im not too good with stick welding yet (all we've done is run a bead, nothing specific) we recently started on MIG though today so hopefully i can use the class (HS Welding) to make a recumbent frame, my teacher recommended using MIG for such a project

[moimeme_81]

when you used spacers to line up the gears was a really good idea, a well tensioned chain will last longer if it's in straight line than if it has to bend... it's the same reason to explain how to shift gears (you try to keep the chain in a straight line) also there is less noise. nice job

[tonyscott]

great ideas mate, thanks a lot

[snowluck2345]

I was wondering, about how much does this weigh? Also, I was wondering, could you base a streamliner off of this? I don't have the money to buy a nice light recumbant. I'm 14 and going into tenth grade next year so I don't have alot of money.

[Layout]

You could easily put a streamliner body around this although it is possibly slightly longer and higher than most streamliners. Alternatively you could limit the body to only the area around the seat with just a tail fairing, and also possibly a small windscreen. The bike is slightly heavier that a steel framed mountain bike but not significantly so. Weight is only important for accelerating and hill climbing, not things you would typically find in a streamliner race.

[snowluck2345]

I was also wondering about the shocks on the front wheel, are those helpful i making a more comfortable ride?

[Layout]

The front shocks are really of very little use. Because of the distance between the seat (center of mass) and the front forks very little impact is felt when the front forks hit a bump. The main reason that the bike has them was because I wanted linear pull brakes rather than calliper brakes and that was the only set of forks that I had. If you have the option rear suspension would be a helpful addition.

[maxpower49]

 just a quick question i noticed you didn't do a part for brakes this isn't a immediate concern because i just got a welder an i am going to start one as soon as it stops raining and i get a welding helmet

[Layout]

The front forks and rear triangle are standard and therefore have the mounts for (in my case) linear pull brakes. The only issue you might run into is if you have side pull caliper style brakes on the rear triangle and you have to cut off the mount where it joins to the seat stay. In that case you may have to fabricate a new mounting system.

[maxpower49]

how would you extend the cables or are they long enough

[Layout]

 I used generic cables and had no problems. If the length did become an issue you could always use a tandem cable for the front brake.

[The Lance Armstrong]

Well done.

[Layout]

 Thank you. Praise indeed :)

[varneyrobert]

Would you recommend a chain guard to prevent anything from getting caught in it ?

[Layout]

 A chain guard might be a useful addition if you plan to ride with trousers. I rode to work in bike shorts so this was never an issue for me. A standard bike chain guard would be sufficient or even just the circular chain guard that attaches to the crank (see spank's picture below).

[varneyrobert]

I know that you no longer have the bike but do you recall any of the angles in the frame?

[Layout]

I never measured any of the angles, but if you use the dimensions included in the text you should not need to be concerned about angles.

When I built the bike the first thing I welded was the top tube to the rear triangle, all the other dimensions/angles simply flowed from that decision.

Conveniently the head tube angle also just seemed to flow out of this decision and it is welded at a right angle to the top tube. This may not be the case in all builds but I recommend an angle slightly shallower that what you would find on a standard bike (i.e. increased trail)

[Layout]

Actually looking at the images and rereading the text I realize that part of my last paragraph is incorrect. The head tube is not at right angles to the top tube but instead at right angles to the bottom tube (i.e. parallel to the other head tube). The remainder of the comment is however correct; aim for a head tube angle slightly shallower than on a standard bike.

[varneyrobert]

How did you get the handle bars welded into the square tubing?

[Layout]

Have a look at the third picture on the steering page.

I popped the bearing races off the head tube and cut/filed a hole big enough to accept it. Once it was welded in place I simply refitted the bearing races.

[varneyrobert]

Thank you

[technodude]

Took my bike for its first ride today, the welds are only tacked, no brakes, the derailers aren't hooked up and I need to install a chain tensioner on the front chain. I only fell down twice..... maybe three times. But its a nice ride. Thanks again Layout Steve

[Timothy Wooi]

you can consider building a 3wheel recumbent ,a delta trike and forget about falling lus having the coolness of a 2 wheel recumbent!
 From tim Malaysia. 

[varneyrobert]

(removed by author or community request)

[Layout]

I would recommend mild carbon steel since you can't weld dissimilar metals and the bike frames are likely steel. Also welding aluminium requires specialized equipment.

[Koosie]

Great Zeus's beard, that's awesome!

You've gone and confused the whole, general bike layout!

Pedal where you're hands were and stear where you're feet were!

[spank]

just completed the bike made from assorted bikes from the tip, great instructable thanks for the great design, i had to re adjust the front rake due to exchanging front ends, now rides and handles great

[darwin-t]

I am making progress. I have the frame done and both wheels attached. It is just tack welded right now. As for the steering,where can one find the "rod ends"? I actually sat on it today, so I'm on the right track.

[Layout]

Most automotive parts shops should carry a selection of rod ends. Or if that fails there are plenty of places where you can order the online. Look at shopping results for "rod ends" on google. It may be easier to go with a 3/8" or 1/2" thread in the US as metric threaded rod may not be as easy to come by. Also check the turns per inch, I know there are a couple of standards for 1/2".

[darwin-t]

I'm building one of these - thank you so much for publishing this. One question - where can one find the high density foam?

[Layout]

In New Zealand I got the rubber from a company that specializes in rubber products (Para Rubber). High density foam is often used as bed rolls for camping so I would try some hunting and camping stores. Let me know how your build goes and maybe post some pictures.

[darwin-t]

Thank for the quick reply. I was trying to build using only one frame, so I deviated from your plan a bit and am sorry now. I have 2 more frames for parts, so I will see how it works out. I started with a gas welder, but the tip was too big. I bought a small arc welder but had so much trouble striking an arc I followed your advice and spent another $70 on an auto darkening mask. That is MUCH better. I'll post pictures when I get it done.

[laundryshoppe]

Great instructions. Actually, you have inspired me to make my own. Yours is the simplest, best looking recumbent I´ve seen. Thanks

[sayoian99]

yes,his looks better than those $1200 recumbents...^_

[CNCOPERATOR]

Since my brother and I are "short wheelbase" we would like to know how high the seat is from the ground. We really like the bike and plan to build at least three this winter. thanks for your reply