Greenspeed Tandem Recumbent Tricycle

June 20...., 2005



So, how did we come to get a trike? It turns out that I took up cycling after my heart attack in 1995. I made a number of lifestyle changes - quit smoking, lost weight, and started exercising. At first, the exercise was walking, which gradually became jogging, and then I got out my old bicycle and started taking it for rides on Sundays as an alternative to jogging. My interest grew and I did the RAGBRAI in 1998 and have done at least one long cross state ride every year since, except 2003 when Jane's problems really came to a head. She suffers from osteoporosis and neuropathy and in the summer of 2003, she lost the ability to walk. After a hospital stay and physical therapy she could get around with a walker, but then fell and broke her hip at Christmas. So more hospital and more PT. She's still using a walker but getting stronger.

Anyway, I had suggested we might get a tandem, so she could ride with me. She's been a good sport and when I do one of the cross state rides, she drives our van with gear across state as well. When she could still walk, she would set up the tent each day. Her reaction to the tandem idea was "one fall and I'm dead because I won't have any whole bones left." That was an accurate evaluation of the situation, so I didn't really push the idea.

One of our friends, Marc, who lives in CA (we live in NJ) had a stroke. He was also an avid cyclist, but the stroke left him with a very weak right leg and an essentially useless right arm. (Fortunately, he's left handed.) Anyway, he made gradual progress and one of the email updates we received had a picture of him on his new Greenspeed trike. When I showed the picture to Jane, she said, "I could do that!" So that's what started this.

I started looking at the Greenspeed web site in the fall of 2004 and thinking about what to get. I decided on a tandem because Jane will need help for a while before going any distance on her own. I thought the convertible tandem would be a good idea in case one or the other of us really got into trikes. But it's very expensive - you could buy a small car for what this trike costs! Also we moved to a new home with a single level, so that took up a lot of time.

Finally, at the end of March, 2005, I started emailing Ian Sims at Greenspeed about the possibilities. After some discussion, I wound up ordering the convertible (single or tandem) trike with the following options:

Also, with the mountain drive, they generally install a single 60 tooth chain ring. Since I wanted really low gearing, they were able to put on a double: 52-38.

The trike is officially a GTVS6 and it's serial number 1710.

The order went in on April 4 or 5 (hard to tell since Australia is almost exactly 180 degrees out of phase from us - actually I think it's 10 hours!).

The trike arrived on June 20th. I took a couple of days to get it together and longer to solve shipping damage problems and figure out how to transport it.

Since getting the trike assembled, we've been taking it out for very short, but gradually increasing, rides together. One thing I've noticed is that you certainly do use different muscles on a recumbent than on an upright.

Update March 11, 2006: We received the stoker freewheel last November. It's actually a new left crank for the captain's bottom bracket. The spider, to which the timing chainring is attached, has a ratchet mechanism between it and the rest of the crank arm which allows it to rotate backwards relative to the arm. In other words, when the captain pedals forwards, the stoker can keep stationary if she wants. Yesterday, we had a nice day and took the trike out for the first time since last fall. Jane gave me a hard time that I hadn't installed the freewheel yet. So later in the afternoon, I put it on. Seems to work fine although Jane hasn't had a chance to try it yet. I also removed the head rests. They just don't work well with helmets.

Update April 29, 2007: I've added a home built chain tensioner to allow the stoker's bottom bracket to seat distance to be changed without having to change the length of the chain. See below for details.

The rest of the story is in the pictures below.


Links: My Home Page, My Photo Albums, My Cycling Photo Albums


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Greenspeed Tandem Recumbent Trike The trike arrived on the morning of June 20, 2005. Here, it's been unloaded by the UPS man. Note that apparently, the up arrows point out the one side which is guaranteed not to be up. Also note the cut and the stain on the box. We later found that a hydraulic brake line had been broken just on the other side of this stain. Jane took all the pictures on this page. Greenspeed Tandem Recumbent Trike We moved the two boxes into the garage. I actually restrained myself and continued doing the errands I had planned on and went to work before unpacking the trike.
Greenspeed Tandem Recumbent Trike About 5pm, I started to work on the trike. I moved one of the cars out of the garage and swept the floor before starting. Greenspeed Tandem Recumbent Trike Before unpacking, we took photos of the damage to the box. This hole didn't seem to have any bad consequences.
Greenspeed Tandem Recumbent Trike On the other side of this hole is where the brake line was severed. Greenspeed Tandem Recumbent Trike There were several holes on the bottom, but nothing bad seems to have happened as a result of these holes.
Greenspeed Tandem Recumbent Trike I started with the small box assuming that it would contain the manual and small parts. Greenspeed Tandem Recumbent Trike Instead it contained the two front wheels, with the air let out! Conjecture: a Greenspeed single (as opposed to tandem) trike fits comfortably in the big box, but the tandem was too big for the box (and I'm guessing, even with the front wheels in a separate box, still too big which might explain the shipping damage).
Greenspeed Tandem Recumbent Trike The two front wheels with the disk brake rotors. The left wheel is nearest the camera. (It has the magnet for the cycle computer.) Greenspeed Tandem Recumbent Trike I start on the big box.
Greenspeed Tandem Recumbent Trike There's lots of newspaper for packing material. Greenspeed Tandem Recumbent Trike Still more newspaper! Australian papers at that!
Greenspeed Tandem Recumbent Trike After filling two trash bags full of newspapers, I can finally see the trike parts. It turns out the trike frame consists of four big pieces which are joined with S and S couplers. If they are numbered 1 through 4 from front to back, then the piece on the top of the box is number 3. It contains the stoker's handlebars. Greenspeed Tandem Recumbent Trike Here's the manual. You have to "read between the lines" if you're putting together a tandem.
Greenspeed Tandem Recumbent Trike I'll take the packing material off what turned out to be the stoker's seat. Greenspeed Tandem Recumbent Trike Still working on the seat. You might notice the torn packing material just to the left of the cross member above my right knee.
Greenspeed Tandem Recumbent Trike While I was removing the packing material, Jane noticed the torn material and the tear in the seat fabric. Greenspeed Tandem Recumbent Trike We decided we should document the shipping damage. (Since it came from Australia, shipping it back did not seem like a good option!) This shows the torn fabric. We believe this arose from rubbing against something else in the box. Just what, we're not sure, since we didn't notice it until several things had been removed from the box.
Greenspeed Tandem Recumbent Trike By now we had enough out of the box that we could see the broken brake line, which gave me a sinking feeling. This shows where we found the line. Greenspeed Tandem Recumbent Trike In this picture, I've put the brake line back to approximately where it should have been.
Greenspeed Tandem Recumbent Trike Now, I'm unpacking the captain's seat. Greenspeed Tandem Recumbent Trike Here's the very front of the trike. It slides into frame piece 1. It contains two chain rings and a derailleur. There is also a chain ring for the timing chain that connects to the stoker's pedals. The bottom bracket contains a Schlumpf mountain drive which has an internal set of gears that give straight through or lower the ratio by a factor of 2.5. It's kind of neat to turn the pedals 5 times while the chain rings only go around twice! There's also a front light which is run by a bottle generator on the rear wheel.
Greenspeed Tandem Recumbent Trike Here's the rear wheel. It has a disk brake (controlled by the stoker), an internal 3 speed hub, and an 8 speed cog set. If you've been paying attention, you'll know that there are 2 x 2 x 3 x 8 = 96 speeds! The main thing is not so much the number of gears, but when everything is put to the lowest gear, it's about four times lower than the low gear on my regular bike. Since the trike with me and Jane on it weighs about twice as much my regular bike and me, and since I sometimes run into hills that I have to walk up on my regular bike, and since you can't fall over on a trike no matter how slow you go, it seemed like a super low gear would be a good thing!

For the afficionados, the front rings are 52-38, the cog set is 11, 12, 14, 16, 18, 21, 26, 32, the internal hub is 1.36, 1.00, 0.73, and the internal bottom bracket is 1.00, 0.40. The tires are 20 inches. So the low gear is 7 inches and the high gear is 126 inches. The is a dynamic range of 18:1, compared to about 5:1 for my regular bike.

Greenspeed Tandem Recumbent Trike Hmm... Australian papers contain the same kinds of things as US papers!
Greenspeed Tandem Recumbent Trike Actually, I'm not reading the paper, but unwrapping some parts. Greenspeed Tandem Recumbent Trike It turned out to be a mirror (and a cyclometer too, I think).
Greenspeed Tandem Recumbent Trike This is frame piece number 2 which contains the stoker's bottom bracket. We ordered a stoker free wheel (so the stoker can rest while the captain pedals), but the trike was shipped with a regular stoker bottom bracket. Greenspeed Tandem Recumbent Trike Still removing packing material from frame piece 2.
Greenspeed Tandem Recumbent Trike Still working on frame piece 2. Greenspeed Tandem Recumbent Trike Here's frame piece 4, which contains the dropouts for the rear wheel. It's equivalent to the rear triangle on a regular bike. Notice the two S and S couplings that attach to the stoker's seat.
Greenspeed Tandem Recumbent Trike Finally, I get to frame piece 1 which contains the captains handlebars and controls (everything but the rear brake and mountain drive), the steering mechanism, and the front axles. Greenspeed Tandem Recumbent Trike Still removing packing material from frame piece 1. At the right of the picture is the right axle and below it is the right brake caliper. The brake line ends in mid air!
Greenspeed Tandem Recumbent Trike Greenspeed supplies a manual and also a video of assembling a trike on both a CD and a VHS tape. After I got it all unpacked and unwrapped, I watched the CD on my computer. The video shows the assembly of a single (not tandem) trike, so you have to fill in the details. The video also suggesst that one assemble the trike on a table in order to save one's back. That didn't look feasible for a tandem trike. Greenspeed Tandem Recumbent Trike I thought I'd start on the back and work my way to the front. Here, frame pieces 3 and 4 are assembled and I'm trying to attach frame piece 2. This turned out to be harder than it looks! It has to do with the S and S couplers. The couplers have what looks like gear teeth except they point parallel to the tube on which the coupler is attached (rather than radially). When the tubes are mated, the teeth of the coupler on one tube fit into the teeth of the coupler on the other tube. This provides the alignment. Then a threaded collar on one tube is tightened onto threads on the other tube which keeps the teeth tightly joined.

This seems to work pretty well when attaching just one coupling. However, the joint between pieces 2 and 3 has two couplings in two tubes that are not parallel! So the only way to get the couplings to mate properly is bend one of the tubes while assembling. (Not far enough for a permanent distortion!)

Greenspeed Tandem Recumbent Trike I found I couldn't get enough leverage on the tubes to get the couplings to join, so I took piece 4 off and tried holding them this way. Greenspeed Tandem Recumbent Trike Success! Here, I'm tightening one of the collars. Note that this piece (consisting of pieces 2 and 3) plus the captain's seat plus miscellaneous pieces of chain and cable, are what is removed when the trike is converted from tandem to solo mode. That is, I should never have to take apart the two coupling between frame pieces 2 and 3.
Greenspeed Tandem Recumbent Trike Now, I've reattached frame piece 4 and am attaching frame piece 1. Greenspeed Tandem Recumbent Trike With the major pieces of the frame together, I can attach the wheels and get the frame off the floor so I don't need to worry about scratching the paint or damaging cables. (I had the frame sitting on cardboard for protection.) I thought it would be easier to pump up the tires before the wheels were attached.
Greenspeed Tandem Recumbent Trike The brake calipers must be removed to attach the front wheels. Greenspeed Tandem Recumbent Trike Here, the wheel goes on the axle.
Greenspeed Tandem Recumbent Trike I've put the brake caliper back on and am checking that the wheel spins freely and the brakes work. There's a separate brake lever for each brake. The captain has two for the front wheels and the stoker has the one for the rear wheel. Greenspeed Tandem Recumbent Trike The rear wheel is held on by a nut on each end of the axle. (No quick releases here!) The coupling for the internal hub gears, the derailleur, the rear brake caliper, and various cables are all flopping about.
Greenspeed Tandem Recumbent Trike Still working on the rear end. You can see the bottle generator in this photo. Also, the brake caliper is mounted on the seat stay. The lever is on the stoker's handlebars. Note that the hydraulic line extends from frame piece 3 at the brake lever to frame piece 4 at the caliper. So, when the trike is converted from tandem to single mode, and frame pieces 2 and 3 are removed, the caliper must be removed from the rear wheel. Admittedly, the rear brake is an optional item, but it seems that it hasn't been thought through as well as the rest of the trike. The chain, shifter cables and electric cables all have sections that can be easily removed when converting from tandem to single. (Of course, I have no idea how you would put a coupling in a hydraulic line!) It seems dangerous to let the brake line flop around, so I tie wrapped it to the frame. When converting back and forth, these tie wraps would have to be cut or replaced. It seems that the rear brake makes the conversion between modes a bigger hassle. We haven't ridden the trike enough to know whether the rear brake is really necessary, but it seemed like a good idea, since with two riders, the gross weight will be over 400 pounds and stopping on a downhill could be tricky! Greenspeed Tandem Recumbent Trike Attaching the stoker's seat. It may be a little hard to tell from this picture, but the rear wheel has no dish. That is, the rim is centered between the hub flanges. So the axle sticks out farther to the right (to hold the cogs) than to the left (where it holds the disk brake). The wheel is on the centerline of the bike. The right side of the rear triangle is farther from the centerline than the left side. A conventional bike has a symmetric rear triangle and a dished wheel.
Greenspeed Tandem Recumbent Trike Attaching the bolts that hold the bottom of the seat to the frame. On the cross member you can see the bosses for mounting the rack and at the bottom of the triangle is a boss for the fender. Greenspeed Tandem Recumbent Trike Tightening the S and S couplings that hold the back of the rear seat to the frame.
Greenspeed Tandem Recumbent Trike Testing out the stoker's seat! Greenspeed Tandem Recumbent Trike Between the last photo and this, roughly 1.5 hours elapsed. During this time we had dinner. While Jane was making dinner (and not taking pictures), I got the front bottom bracket on (it slides into the front of frame piece 1), as well as the pedals and the captain's seat. I think the rear rack and fender were installed as well.
Greenspeed Tandem Recumbent Trike Looking up something in the manual. (I forget what!) Greenspeed Tandem Recumbent Trike I think I'm installing the rear derailleur. In any case, it's after 11 pm, so I called it a day shortly after this photo was taken.
Greenspeed Tandem Recumbent Trike Sometime the next morning. By now, the chains, front fenders and mirrors have been installed and the shifter cables have been connected. I'm installing the head rests. Greenspeed Tandem Recumbent Trike Still working on the headrest. Jane tried it out and then I made additional adjustments.
Greenspeed Tandem Recumbent Trike I'm using a regular bike work stand to get the back wheel off the ground. Earlier, I did this to check the shifting. Now, I'm trying to get the lights working. Notice the tie wraps along the frame. These are to hold the electrical cable for the lights. However, the tie wraps that came with the trike aren't quite long enough to get fully around the frame tubes. Eventually, I went to Home Depot and bought a package of really big tie wraps. Greenspeed Tandem Recumbent Trike I had trouble with the lights. The back light worked, but not the front light. Here, I'm checking cables.
Greenspeed Tandem Recumbent Trike Here, I'm checking the wiring on the front light. After much fussing around, I concluded that the only thing that would explain all the symptoms was that the bulb was not making contact with the socket. Bending the socket contact cured the problem. Greenspeed Tandem Recumbent Trike Finally, after about 10-12 hours of unpacking and assembly, it's ready to go (or as ready as it's going to get). As you've seen, there was shipping damage to the right front brake and to the stoker's seat fabric. Also, a regular stoker bottom bracket was supplied rather than a free wheel and an extra bar (for mounting accessories like a GPS receiver) was omitted. Greenspeed (e.g. Paul Sims) was good at getting everything squared away (except the free wheel is still in the works). A new seat cover, brake parts, and extra bars were sent from Australia.
Greenspeed Tandem Recumbent Trike And I'm ready for a test ride! Greenspeed Tandem Recumbent Trike OK, once you have the trike, how do you transport it??? Well, given how long it took me to get it together, breaking it down for transport and reassembling at the start of a ride did not seem feasible. Another approach would be to carry it on top of our van. But the basic trike (without options and add ons) weighs about 70 pounds. Sure, I can lift 70 pounds, but at the end of a long ride when I'm tired? Also, it's an awkward 70 pounds! We've got a receiver hitch on our van (used for a bike rack), so I bought a utility trailer that we can tow with the van. Its bed is 5' wide by 12' long. (The trike is over 11' long!)
Greenspeed Tandem Recumbent Trike Another shot of the trailer. Getting it turned around in the driveway was a good trick! Greenspeed Tandem Recumbent Trike It needs fittings to hold down the trike and my regular bike, so I pull it away from the trees for access to the ramp.
Greenspeed Tandem Recumbent Trike I put the trike on to see where to attach fittings. Note that now there are water bottles - there are four sets of water bottle cage bosses. There's also a mini pump mounted under one of the water bottle cages. (The supplied bolts were just long enough for the cages - I had to get longer bolts for the one with the pump mount). Also, there's a bag attached to the rear of the captain's seat for holding tools, spare tubes, patch kit, etc., and a battery operated flashing light on the rear of the stoker's seat. Greenspeed Tandem Recumbent Trike Working on the trailer. Here, one can see the bag attached to the rear of the seat.
Greenspeed Tandem Recumbent Trike Changing the bit in the drill. Greenspeed Tandem Recumbent Trike For the trike, each wheel has a door handle on either side, with a belt and buckle that runs through the handles and over the wheel. This holds the wheel down to the bed of the trailer. With the brakes on, the trike won't go anywhere! (By the way, you put the brakes on with a velcro strap or rubber band around the brake lever and handlebar.)
Greenspeed Tandem Recumbent Trike The trike is tied down. Greenspeed Tandem Recumbent Trike Another shot of the trike fastened down. By the way, you may notice some red sticking out behind the stoker's seat. We have a Jandd Grocery bag pannier (we ordered two, but only one was shipped) and another bag on the back of the seat.
Greenspeed Tandem Recumbent Trike The trike is a little over 3 feet wide, so there's room on the trailer to carry at least a couple of regular bikes. I'm installing a fitting to hold the fork of a regular bike. Greenspeed Tandem Recumbent Trike Here's my regular bike mounted on the trailer.
Greenspeed Tandem Recumbent Trike The rear wheel is held down with the same scheme as the trike wheels. Greenspeed Tandem Recumbent Trike You have to register trailers with the department of motor vehicles. So I did, and got a license plate which I'm about to install.
Greenspeed Tandem Recumbent Trike I also used the shop at the lab to make some fittings for attaching the front wheels to the trailer railing which I installed. You can see one of them just in front of my leg on the inside of the railing. Greenspeed Tandem Recumbent Trike The fitting uses a seat post quick release binder bolt, an aluminum bar with a hole and slot and a small piece of aluminum with a slot. The quick release skewer of the front wheel tightens down on the aluminum pieces and the quick release binder holds the bar to the frame. When not carrying a wheel, the binder holds the two pieces to the railing.
Greenspeed Tandem Recumbent Trike Greenspeed sent me a replacement seat cover, but I had to attach it myself. Here I'm getting ready to take off the old one. It's a giant bungee cord on the back! Greenspeed Tandem Recumbent Trike Here are the scratches in the paint under the torn fabric. The lighting makes them look worse than they are.
Greenspeed Tandem Recumbent Trike The scratches are a little less noticeable in normal light. Greenspeed Tandem Recumbent Trike Lacing on the new seat cover. It reminded me a little of lacing shoes and stringing a tennis racquet.
Update April 29, 2007: As it turns out, I ride the trike with "guest stokers" fairly often. It's a pain to change the length of the chain when the stoker's bottom bracket is moved to accommodate different sized stokers. So I decided a chain tensioner would be a good idea. After making some measurements and some drawings, it appeared that almost 9 inches of chain would have to be taken up to accommodate the range of positions of the stoker's bottom bracket. I considered a Paul Melvin tensioner (for fixed gears), but it didn't have enough capacity. I also considered derailleurs, which have capacities over 20 teeth (9 inches = 18 teeth), but derailleurs pivot about the end and so would require clearance for roughly an 8 inch diameter circle (or at least a semicircle!). Even if a commercial solution might be made to work (I didn't see how), it still appeared that to get the idlers in the correct plane, some custom hardware would have to be built. So I decided to roll my own.

In case others want to build something similar, I've included the details below. Some things that are special to the GTV that may not apply to other trikes are that the bottom bracket, not the seat, is adjusted to accommodate different stokers. Also, the top run of chain is the non-drive chain and is the place to put a tensioner.

Greenspeed Tandem Recumbent Trike A drawing showing the location of the idler under the captain's seat at the upper left and just to the right, the lower bolt holding the seat back to the frame and farther to the right the upper bolt holding the seat back to the frame. These are shown horizontally here, but actually the line connecting the bolts is at the same angle as the seat back.

The stoker's chain ring is shown at five positions. Closest to the stoker is black. This is as close as it can get before the bottom bracket clamp runs into the lugs of the S&S coupler. Farthest from the stoker is green. At this point the toe clips on the pedals are about to hit the back of the captain's seat frame. The dashed line is the chain line without the tensioner.

Tick marks around the edge are at one inch intervals.

The tensioner idlers are shown so exactly the same amount of chain is used at each position of the stoker's chain ring.

Greenspeed Tandem Recumbent Trike A view of the trike showing the captain's seat and the stoker's bottom bracket in the configuration where the bottom bracket is as close to the stoker as possible (without clamping on the S&S lug). The S&S coupling is just behind the back part of the chain ring.

This is before installation of the tensioner.

This picture can be compared with the drawing by orienting the tube behind the captain's seat horizontally. The screws shown in the drawing go through the middle of the frame tube.

Since this is a GTV (convertible to a solo trike), the power from the stoker goes to the captain's rings and then all the way back to the rear wheel. The bottom chain is the power chain and the top is the return.

Greenspeed Tandem Recumbent Trike The view from the other side. The S&S couplers can be seen about even with the back of the stoker's chain ring. Greenspeed Tandem Recumbent Trike From behind the captain's seat. The seat bolts, originally 8mm x 70mm have been replaced by 8mm by 80mm so there is an extra 10mm of threaded bolt sticking out to the left. (A little hard to see.) As it turns out, I only used the top bolt to mount the tensioner, but maybe I'll think of something to do with the bottom bolt.

Also, one can see the clamp that holds the bottom bracket to the frame. There are four screws that hold the bottom half to the top half (screwed in from the bottom!).

Finally, one can see the lugs associated with the S&S coupler.

Greenspeed Tandem Recumbent Trike All the parts of the chain tensioner. All the stainless steel bolts, washers and nuts are from McMaster Carr. The steel pieces are 3/16 x 3/4 inch steel stock from Home Depot and the idler wheels are Greenspeed 15 tooth idlers from Hostelshoppe. The steel pieces were cut with a band saw, shaped with a sander and drilled with a drill press (using the shops at our lab) and painted red to match.

From the bottom: Screws for the idlers, 10mm x 20mm. The idlers. 10mm washers to act as spacers between the idlers and the idler bar. The idler bar tapped for 6mm thread in the center and 10mm thread at each end so that the center to center spacing of the idlers is 3 inches. 6mm x 14mm screw and two 6mm washers to fasten the bar to the mounting bracket. The three pieces of the mounting bracket and two 6mm x 14mm screws to hold it together. An 8mm nut and washer to attach the mounting bracket to the seat bolt.

The mounting bracket needs an offset to get the idlers in the right plane. So it's made in three pieces: the top part, the spacer, and the bottom part which is tapped for the 6mm screws. The center to center distance from the seat bolt to the bolt holding the idler bar is 3.86 inches. The spacer is 0.4 inches wide centered 0.7 inches from the seat bolt. (This gives room to clear the seat mounting bracket and the idlers.)

Greenspeed Tandem Recumbent Trike The assembled tensioner. Actually, the chain won't fit through the gap between the idlers, so one of them must be removed and replaced when installing the tensioner on the trike.
Greenspeed Tandem Recumbent Trike The other side of the assembled tensioner. Greenspeed Tandem Recumbent Trike The tensioner installed on the trike with the bottom bracket as close to the stoker as it can go.
Greenspeed Tandem Recumbent Trike From the right side. Greenspeed Tandem Recumbent Trike The tensioner with the bottom bracket as far away from the stoker as practical. At this position, the toe clips overlap the cross piece in the captain's seat. However, most people don't pedal with their toes pointed, so it's still a useable configuration.

The tensioner is not spring loaded like a derailleur. Instead, it's rotated to the desired position and then the bolt holding the idler bar to the mounting bracket is tightened. This bolt is the same size as the bottom bracket clamp bolts, so one allen key does the whole job.

Greenspeed Tandem Recumbent Trike Viewed from the right side.