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Click HERE to go back to the Andy Douglas Streamliner page.

Andy Douglas' streamliner - the bike

Photos: This picture shows the bike before all the mods described in the text were made.



About the bike
Originally I was going to build a bike specifically to go inside the shell, and to that end have been accumulating parts and making drawings. Click HERE to see the article about the design process.

However, I ran across a ready-made bike that would serve the purpose pretty well, for a reasonable price, so I bought it. It's a Pharobike Lowfat, which bears a striking resemblance to John Tetz's designs. Since I'm modeling my streamliner on his, it's just what I need. This bike was introduced in 1999/2000 as a production model, but only a few were built before the designer, Dan Duchaine, died of a sudden illness.

Aside from being very small, the Pharobike is also quite light. I've made a number of changes to mine, some of which lightened it, others which added weight. As of right now, the bike weighs 25.5 real pounds.

This includes the following alterations/additions:
- New pedals
- Rear rack
- New tires
- Megarange gear cluster
- New handlebar and riser
- Larger power-side idler pulleys
- Front suspension hub
- New front brake
- Larger front wheel and tire
- Computer with cadence, plus separate HRM
- Bar-end mirror
- Heavy-duty "glove compartment" bag (see photo below)

The bike as originally built does not have a reputation as a very fast machine, and indeed I found that the stock setup left something to be desired. As delivered, the bike had a 406 rear and 305 front with heavy, low-pressure tires. The stock idlers were rather small, and allowed the chain to rub the bottom of the seat when in the lowest gear. The tiller stem was heavy, and the stock BMX handlebar was very wide, placing the rider's hands rather far out to the sides. The supplied pedals were 500-plus gram combination SPDs... fine for a commuter bike, but I don't really want to be slinging a pound of mass around all day long if I can avoid it.

I immediately made some changes to improve efficiency, ergonomics and ability to function well in a fairing.

Steering



The first thing to go was the tiller steering. Forcing the hands back into the belly (the "praying hamster" position) forces the elbows out, which makes the fairing fat, which is not good. I opted for a "Superman" riding position, in which the arms are stretched out comfortably, with the forearms just outboard of the kneecaps, and the shins just clearing the bar. The bar is very short, so the hands are in front of the knees for the most part.

To accomplish this, I replaced the tiller stem with an adjustable Kalloy stem off a hybrid bike and replaced the BMX bar with a simple piece of 7/8" aluminum tube about 14 inches long, bent slightly in the middle. (As a side note, the tubing used for bike handlebars is much thicker and heaver than is required for a recumbent, because it is intended to support the weight of a rider. I used very light stock tubing from the hardware store.)

The bar has to be above the shins (in front of the knees) to clear my legs properly. So, to be able to reach the bars (and see over the top of the fairing), it's necessary to set the seat as upright as it will go. It's now a rather upright 50 degrees from horizontal. The resulting riding position is very much like that of a comfortable sports car, with my arms extended but relaxed, positioned where they would be on a steering wheel. Those with longer arms than I have would be able to recline more.

The clearances are set very tight. I had to rotate the grip shifts so that the cables exit above the bar, since there isn't enough room underneath to clear my shins. I ride with my thumbs tucked in underneath the shifter cable housings, because they lightly touch my shins if I put them underneath. Everything does clear, however.

It's important to note that what I've done won't work if you're a large person. I'm 5'7" with a 30 inch inseam. Those with long or very thick legs probably wouldn't be able to get away with making these changes. The bar would have to be raised considerably to clear the legs of a taller person. I KNEW that someday I'd discover an advantage to being short!

Wheels/tires
I immediately chucked those awful stock tires and put Primo Comets on the bike. While not my favorite tire, they're light and have very low rolling resistance. I used the new fat 406 version for the rear. The tire swap made a huge difference in rolling resistance.

I have issues with 305 front wheels. The smaller a wheel is, the greater the effect of rough pavement and potholes on handling and rolling resistance. Duchaine chose the 305 because he wanted to ensure emergency-spare availability, and 305 wheels are much more common than 349s. I elected to retrofit the larger wheel; after all, I'm not touring here. Being able to go into a Wal-Mart to buy a tire doesn't matter to me.

I discovered to my delight that there is enough room (JUST enough room) to fit a 349 wheel on the bike. There's less than a forefinger's width of clearance at the down tube, and slightly more than that at the fork crown. The crank arms clear by about 2 mm, and the chain clears by about 5 mm. Everything works, and the bike handles very nicely. The swap also raised the front end of the bike an inch or so, which is good for fitting into the shell.

One inevitable side effect of putting a larger wheel on is the relaxing of the head tube angle. It's now roughly 69 degrees, which with the straight fork gives me a lot of trail (haven't measured it). The bike handles quite nicely, however.

The one possible show-stopper for this swap was the brake. I really didn't want to go with caliper brakes if I could avoid it, because of the high average speeds of a streamliner. One day I was randomly flipping through a bike catalog and ran across the Paul Components Motolite V-brake (http://www.paulcomp.com). This is notable because the pads adjust by means of a collar on a rod-like brake arm, instead of the more conventional (and too short for my needs) slot.

It turns out that they also make a brake specifically designed to allow larger wheels to fit on bikes that have canti studs (the MotoBMX). In this case, it's meant for MTB riders who want to use 700C wheels, but no matter.... it was the perfect choice. Expensive ($100 just for one brake), but ideal. Also very light and very powerful. I may put one on the rear at some point, since the mini-V brake that came on the bike is not very powerful.

Also, I recently became aware of the Pantour suspension hub (http://www.pantourhub.com). This is a front hub with a short-travel elastomer suspension element built into it. Because of the tight clearances caused by the shift to a larger wheel, I was fearful that it would have interference problems. However, the hub is designed in such a way that at rest it displaces the axle centerline down and forward, thus increasing the effective clearance to allow for suspension movment. I ordered one and it does indeed fit. At rest with me on the bike, the suspension deflects somewhat, putting the axle more or less where it would be on a conventional hub.

As of this writing, I've tested the hub on one 28-mile ride during which I went out of my way to look for bumps, potholes and rough pavement. The hub does indeed work as advertised, taking the sting out of what would otherwise be sharp jolts and making tar-and-chip surfaces much less unpleasant. The weight penalty is very small, as well... the hub weighs 220 grams, less than 100 grams more than a conventional hub. This is much, much lighter than any other front suspension option.

Despite the tight clearances on the bike, I had no problem with the tire hitting any part of the bike during this ride. Also, the brakes worked just fine and handling seemed to be unaffected.

Drivetrain
Part of the bike's slow reputation comes from the drivetrain design. Two relatively small idlers on the power side combined with a Sachs 3x7 hub add up to a lot of inefficiency. Initially, I wanted to improve this by eliminating one of the idlers and running the power side of the chain alongside the front wheel. However, after seeing the bike it was obvious that this would not work. I'd have to live with two idlers, so I did the next best thing: put on bigger, better ones.

I have replaced both power-side idlers with 4" nylon V-belt pulleys from McMaster Carr (http://www.mcmaster-carr.com, item 6234K45 - Nylon V-Belt Idler Pulley 3/8" Bore, 4" OD, .70" Wide, $6.45 ea.) These are heavier, but more efficient. They also eliminated the chain/seat rubbing problem with the stock gearing.

To get a better gear range I replaced the stock 11-28 cassette with a Shimano 11-34 Megarange unit. I now have an excellent granny gear (19.8 gear inches), at the cost of a bit of rough shifting under load when the chain moves onto or off of the granny cog (it's a whopping 8 tooth jump to the next cog). I can live with that for the hill-climbing ability it gives me. Also, initially the bigger granny brought back the seat rub problem, though it wasn't quite as bad as with the stock setup. Adding an appropriately sized O-ring to the pulley solved this and also silenced the drivetrain.

The bike came with short BMX cranks (155 mm), which I've found that I really like. The short cranks bump the cadence up by at least 10-15 rpm, and feel great. They also keep my feet from moving very far vertically, which is an issue when inside the fairing (the smaller the circle described by the feet, the smaller the nose can be). Also, with my leg length and the larger wheel, longer cranks would have resulted in crank/wheel overlap. A side effect of the short cranks is a reduction in leverage, which means I'm pushing a bit harder than I would be if I had more conventional 170 mm cranks.

I replaced the heavy stock pedals with the lightest SPDs made (WTB Stealth MP250s, 260 grams/pair). The legendary Power Savers never got put on the bike.

The ride
The bike is now quite sweet-handling and pretty darned quick. It's made of thin (.035) CrMo tubing, so there's quite a bit of what builders euphemistically call "passive suspension" (frame flex) built in. With a very short wheelbase and very low center of gravity, the bike is fantastically nimble, much moreso than almost any other recumbent I've ridden (Tetz's yellow bike is the exception: it feels almost the same). For comparison purposes, the second-most nimble bent I've ridden is my wife's RANS Rocket. So if you know what that's like, imagine it being better and you've got an idea.

Despite the inefficient drivetrain, it seems about as fast as my Wishbone (plus or minus one or two mph at a comfortable cruise, without the fairing) and climbs quite well. There's a caveat here: I don't have a lot of miles on the bike, so I'm not willing to make extravagant claims just yet. I need more data. So far, though, I'm loving it. Will it replace my beloved Wishbone? I don't like to say "never," but you never know. For now I'm keeping both. If I find that I just don't ride the Wishbone any more, then I'll sell it.