EZClone Recumbent Bicycle Plans

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Plans for building a recumbent bicycle using parts from old bicycles and some generally available hardware. Build your own bicycle comparable (with similar form and function) to ones costing hundreds of dollars.

Transcript of EZClone Recumbent Bicycle Plans

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SHEET 1 - Donor bikes If you have choices you can make about what bikes to use, focus on three things.One Steel tube bikes, or chro-molloy. Avoid (unless you have the welding skills) Aluminum, and oversized tubings. Two hardware. I look at the crank you want a three piece cotterless crank bike at least for the one you use as the front end of the bike. The cotterless crank with the narrower (roughly 1 5/8 Dia) bottom bracket, offers you the most choices later for upgrading hardware different cranks, sealed cartridge bearings, and so on. Three weight. Steel bikes come in an endless variety of tubing thicknesses, all of which contribute to the overall weight of the bike. If its a boat anchor, move on. If its a featherweight racer the odds are that a first time metalworker will have a hard time with such thin tubing. Reference for new mechanics. Brad Graham's book, "ATOMIC ZOMBIE'S BICYCLE BUILDER'S BONANZA", has a superb section early on about how to strip a bike down to it's bare frame. I don't know if his website has the same info on it, but it is worth a read for the new mechanic (and for alternate building inspiration!). If you are following along here, DON'T chop the frames up the way he does - it ain't wrong, but it isn't the method detailed here. Where possible I like to re-use the fork and head cups/bearings from this bike on the finished recumbent. Matched parts and all.

SHEET 2 - Same notes on donor bikes, except you dont need to worry about the crank from this bike. Ithelps if donor bike #2 is a really tall frame, we use all the length of the old seat tube here. I strip the paint off of all bike frame parts I salvage. You dont want to weld/braze over paint jobs, and youll burn existing paint beyond recovery anyway. I use a torch in a well ventilated area to toast the old paint on bike parts, then I wire brush them clean. Please be careful, and no not breathe toxins.

SHEET 3 - The first assembly is the easiest no alignment to do. The most difficult cut is the fit for the oldseat tube under the top tube. Pre-assemble the sleeve joint with the top tube offset slightly over the old seat tube, and mark the angle of the intersection. Cut carefully at this angle, but to 3/8 longer than you need it (there is a picture reference for this cut Picture Page 1). Then file a fishmouth onto this end, removing material towards and away from the head tube in a curve to meet the underside of the top tube as closely as possible. File and fit, file and fit, until you get it right. The down tube is a spliced sleeve joint. Usually a small piece of salvaged toptube, smaller in diameter than the down tube, makes a perfect inside sleeve for the joint. Braze or weld these two joints. Be sure to flux and heat the sleeve joint thoroughly so that braze material penetrates deep into the joint. The second assembly is easier to fit, and harder to align. For most common donor bikes, the top tube of the front donor bike will sleeve nicely into the old seat tube of the rear donor bike. Length factor you. I am an average 6-0 person, and about 38 long for a top tube is generous for me. A frame for a truly 5-0 and slightly smaller person might have a total top tube length of 34 - this is probably a minimum. A tall person 6-4, say, might want a 40 top bar. Trim the old seat tube from bike #2 to adjust length and overlap. Before welding/brazing, lay the unbrazed assembly flat on a table where you can weld. Make sure the head tube and bottom bracket arent on the table interfering with the tubes lying flat, and use washers to shim the front (narrower) portion of the top tube and the (Bike #2) cross bar so that everything is parallel on the table. This really is your first critical alignment - take the time to jig and shim this into shape.

SHEET 4 - Try bending the rear triangles salvaged from both bikes. I guarantee you will like one of themmore than the other one after bending (do this before stripping the paint off the chosen part). I use the torch to heat both top stays at the same point (on the inside of the stays), and then I press the bend in by hand down to the height shown. Someday I will make a jig to do this more evenly. One correspondent uses a conduit bender to do this bend cold - I haven't mastered this yet. The top ends of the top stays are heat-bent as well. I hold the part in a vice with both ends sticking up (Picture Page 2). Heat the stay about 2 down on the outside, and then bend it out about 10 degrees (I use a 18 piece of conduit as a bending lever). Do the same on the other stay. Then heat the inside of the first stay at a point about 3 down from the end, and reverse the bend 10 degrees back. This brings the original bend back parallel to the center axis. Do the same with the other stay this should align both stays parallel to the top tube you are about to attach them to, and just at the right width to press tightly to either side of what was a seat lug. Have the cut-off seat tube end from bike #1 in hand (from your trash pile) to test this as you heat and bend. You may have to come back and fiddle with this bend again - as you mechanically assemble the rear triangle to your bike and make judgements about alignment, you will want to fiddle with this bend. The THIRD assembly, adding the rear triangle to the bike, is the trickest to align and the most telling on the finished bike. This can be jigged and measured for your assurance there are very fancy alignment tables and micrometers for just this purpose. Fortunately, the EZ Clone geometry is a very forgiving geometry for rear triangle alignment a thorough set-up and visual inspection will do for alignment. I set the existing partial frame perpendicular to the table and upside down. Then I set-up the rear triangle on the table, shimmed up (on 3/8 spacers) and already in place with the top stays pressed onto the bikes top tube. In the rear drop outs I put a 36

long white rod with a center marked and set in the center between the drop outs (Picture Page #2). I stand off 6-8 feet and eyeball the resulting alignment from front and back. Is the white rod centered on the frame as well as the drop outs? Is the rod visually parallel to the table, visually perpendicular to the frame? Is the apparent triangle formed by the stays and the drop-out visually equal on both sides of the frame? Three or four trips to the table, and I am satisfied with alignment from the rear view. Now go to the front of the bike, stand off 6 feet, and eyeball it again. Yes? No? Often I find the front view and the back view are different in perception, and I will go back and forth from one to the other until I get an alignment I like from both ends. Now stand off to the side of the bike hold the drawing upside down and nearby does it look like that? Top tube and top stays parallel and aligned? Check the other side. Lastly, I put a hub cut from a salvaged wheel (no rim, no spokes) into the rear triangle dropouts. I look at all the alignment points yet again to decide if all is well. Its worth the trouble. Weld/braze the top tube and the stay in this position on both sides, along the 2 point of contact between the two parts. Both sides, then flip the bike over and weld/braze on top of the joints. Over do it, fill the gaps - this is where the weight of the rider bears most. NEW THOUGHT 8/18/03 - After this assembly I have taken to putting the unfinished bike in the stand and mounting a wheel in the rear drop outs. Check alignment now - is the wheel in plane with the frame? Tilted up to down? Hand bend the stays a little - you can do this cold with the handle of a hammer for a lever. Out of plane front to back? Leave the wheel in the frame, put it on the floor on it's tilt-to side, and gently step on the newly brazed joint to adjust. It sounds weird and crude, but it works. Get satisfied with alignment now, before we lock it in by adding the bottom rails in the next step.

SHEET 5 - Bottom Rails. You can use something finer and lighter than EMT tubing if you want to. I dontmind. Before doing the final assembly, check out Sheet 6 about bell-forming the ends to join over the donor bike stubs. Those stubs are often oblong and strangely shaped (often crimped) depending on the stays from the donor bikes used, and the bell shaping idea allows you to cope with all those variations. Test assemble one bottom rail. When you like that, repeat it for the other one. The 5 degree bend is useful for spreading the rear triangle slightly. As you assemble the frame with the open bells, rotate the bend out slightly and evenly to align the bottom rail with the bottom stay on the rear triangle. When you have what you like, clamp the two tubes tight against the downtube. Stand off to the side. Like it? Look like the picture? Adjust while you can. Stand to the rear. Put a wheel in the drop outs - is alignment still OK? Fix it. Like it? I leave an old wheel (no tire) on the frame throughout the process of adding these bottom rails. Right up until the point where you braze the final joints, I continue to stand off and check visual alignment. Braze weld both rails to the downtube right where you are now, without closing the bells. This freezes the rails in position. Now heat and bend/form the bell ends over the bike frames stubs. Do this thoroughly and carefully on all four joints leave no gaps where the edges of the bells lap over the stubs of the donor bike. NEW 8/18/03 - Put that wheel back in the frame at this point - check the alignment and adjust. Clean, wire brush, and flux everything. Braze all joints thoroughly, from top and bottom.

YOU FINISHED THE HARD PART THIS IS (almost) THE FINISHED FRAME!!!!!!!!! A note on EMT. You are burning noxious chemicals off of the EMT as you heat it - zinc galvanizing to say the least. Ventilate thoroughly do not work in an enclosed space. Do not do this for a living not a good idea at all! See notes above on when and how to close the bell flaps onto the bike frame stubs. This process may take a few practice tries before you do the actual work on the bike, eh? Cut off the extended stub of the 'back' downtube flush below the bottom rails.

SHEET 7. Time to admire. Does your frame look good to you? Still like that rear end alignment? What isright? What is wrong? What can be adjusted? Like it enough to finish it? Every third or fourth frame I do, I still find one that gets away at this point. Sometimes an alignment boner I can fix with cold bending, sometimes not. Sometimes an error in proportion. Is it fixable or not? Sometimes a gap in a brazed joint those you can fix. Now is a good time to decide whether this frame is worth taking through the rest of the process of becoming a great bike. Depending on the donor bike and the bend in the rear triangle, usually a 26 wheel is the easiest fit with the existing brake bridge on the top stay of the rear triangle. Sometimes a 27 wheel will fit. If you really want a 27" cut this brake bridge loose now and add your own. Or add canti studs, etc. C. The chain idler is not really necessary. It helps carry the weight of the extra chain which is otherwise pulling on a deraileur spring that wasn't designed to hold it, and it keeps the chain (potentially) out of the dirt. I drill a piece of threaded rod through both bottom rails of the bike in the position shown, and mount an idler wheel salvaged from a rear derailleur on it between a couple of 2 plastic washers. NOT SHOWN - I usually run the very long rear deraileur cable along the bottom, right hand rail, much the way it is run on the typical 10 speed road bike. I add one extra (usually salvaged) cable stop braze-on, just behind the rear down tube and ahead of the 5 degree bend on the right rail. This acts as a slight mule block for the rear deraileur cable and keeps it from fouling the chain.

SHEETS 8-10. Parts. This is the slung seat I use. I can and have hung a Rans seat on this bike. And youcan make a plywood seat and get by just fine. I like this one a lot rode 150 miles on it with a broken tailbone, no less! But that's another story. The secret of bending that really odd shape is to mount a conduit bender in a table height bench vice. Then bring the EMT tubing, thoroughly marked, TO the bender. EMT bends pretty easily by hand, yet is rigid enough to stand up to this 270 lb. rider without deforming. Bend the bucket, the 90 degree bend, first. Then bend the 45 degree base ends. Take care in the bender to visually align each bend on the same axis at the first bend. Buy extra conduit, make extra tries at bending it just right. Conduit is cheap make four (4) side rails and choose the best two for your seat. A full sized pattern is a help. Seat braces. I make the bottom brace from EMT this part bears the riders weight over the bike's top bar. Do draw a full scale pattern for this. Lay your finished, bent brace in this pattern before cutting to establish exactly where to cut off the braces. Have an extra bit of 1 1/8" bike tubing handy to use as an extension on the EMT you are bending you will want the leverage. Seat covers. I use a vinyl mesh fabric Power On Cycling sells a very good mesh for seats in small quantities (want a bolt I know the wholeseller!). I hear there is a great rip-stop nylon fabric for sale at REI that works too. I stitch my covers on around the seat rails with nylon monofilament. Looks great. It is possible to stitch and

grommet a separate cover and lace it onto the frame. Or to do what Rans and others do in the way of a cover that wraps around the the back of the frame and then is cinched with zipties. SHEET 9. Seat stays. This item, bolted onto the extra holes in a rear drop-out, is a fairly good, lightweight way to hold up a seat back. There are other ways. Like this: A 5/16 steel rod from Home Despot sleeves very nicely into a 3/8 aluminum tube from the same source. Flatten one end of the tube and drill and bolt onto the drop out. Weld a nut onto the end of the rod and invent a pivot bracket on the back brace of the seat. At whatever adjusted height you like for the seat, drill through the sleeved rod and tube and set a cotter pin. Simple. My seat stay works pretty well you can screw the bracket up and down the threaded rod (within limits you dont want it poking through the seat cover). For a shorter riders you can add threaded sections onto this stay assembly to extend it forward. For riders that want to lean back farther - cut off some threads!

Seat bottom bracket simple, effective, easy to make. This and four hose clamps and I have all the adjustability I need. Steering Post. This is what I make, for two reasons. One, I am cheap. Parts are virtually all salvage, and a 1 handlebar stem sets very well inside standard EMT tubing. Two this stem is infinitely adjustable. I can make it very long for my comfort, or cut it off easily for a rider with longer reach.

The bent-over flaired stem from an old racing handlebar crimps quite badly when heat-bent this way (heat the inside of the bend, not the outside). But when you heat the crimp up and fill with brazing rod, it gets quite strong. Bend and bell form the conduit piece first. Then add the handlebar stub and braze this together. Make the crimpbend last before filling, adjust it to align perpendicular to the long axis, and then braze/fill the crimp. SHEET 10. The bike uses the original fork, which has a brake mount in the crown where you won't need it. You are going to use a 20 wheel (You can use a 16" wheel instead - try both and see what feels best to you for handling), so you need to set a new bridge in this way. Fancier alternatives? You could buy and set a manufactured bridge in the same spot. You could buy parts for cantilever brakes and mount those. I havent broken an EMT bridge yet.

ASSEMBLYNotes on parts. Again, I dont here go into the nuances of bike parts and assembly of your finished bike. You can salvage the 10 speed (or whatever) gear train components from the donor bikes and apply them to your new bike. I do this, with the best components at hand, for every 'new' bike I make. Rely on your ingenuity to string cables and guides for the deraileurs and brakes front and back. The chain line takes roughly 2 1/2 standard length chains. I do suggest you go all the way through your assembly and test-ride the bike before you go on to finishing and painting. You might want to braze on a cable stop, or file away a clearance, and so on. Assembled? Time to test it, see what you like, see what you want to adjust. Deep breath, and push off! Get happy for a week or so, be patient. When you have it how you want it, now is the time to strip it all down again and finish and paint!