Friday, October 21, 2011

Bearing Some Resemblance to a TerraTrike Rover

I've had a recumbent trike or two over the past couple years, and some months back I convinced my better half of the benefits of 3 wheeled transportation.  She didn't like the ultra-low seating position some of the tadpole-style (two front wheels, one back wheel) trikes were sporting, so we settled on the design of the relatively new TerraTrike Rover.  Its seating position is higher than most of its class brethren while still remaining stable enough for cornering at our regular cruising speeds (without lifting the inside wheel off the ground).  My initial issue with the model was its lack of wide range gearing.  It was available only in a 3-speed or 8-speed internally geared hub configuration which didn't give quite the desired range our hilly area requires.  After some searching I ran across a custom build being done by Utah Trikes: the Rover 8 DL.  Basically they pull the internally geared rear wheel and replace it with a standard rear wheel with 8-speed cassette and rear derailleur.  What's the benefit of that, you ask?  This allows the single front crankset to be replaced with a triple crankset giving more gearing options than you could ever need.  Utah Trikes will even install the triple crankset option complete with bolt-on front derailleur post for a modest $150.  Convinced we now had a winner, I placed the order and waited with baited breath until the day of the huge box delivery arrived.  The trike shipped almost completely assembled and it was up and running in very short order.  The Rover is a great recreational riding trike - very maneuverable, easy to get in and out of, and above all very fun to zip around the neighborhood on.

The great build configuration by Utah Trikes left me wonderfully content... for about a week.  It was about that time that the economy-level drivetrain components and tires left me yearning for better ride quality and crisper shifting (the trike came configured with very modest level SRAM X-3 components which shift a bit imprecisely).  With a few flicks of an allen wrench (and turns of a cassette lockring tool, chain whip, channel lock, wire cutter, and even a few squirts of hairspray to slide grips on and off), the Rover was now sporting a 9-speed rear cassette, Deore rear derailleur and SLX trigger shifters. 
Soon after, the cheap no-name low-pressure tires were replaced with a trio of beastly Maxxis Hookworm tires better capable of handing the suburban jungle in which we reside.  Better shifting?  Check.  Better ride?  Check.  Ahh, content again... sort of.

A few minor tweaks ensued.  Bolted on a rear rack for the pannier bags, added a bike computer and added a chainring guard (the ICE Trice Chainring Guard fit wonderfully).  As I mentioned in previous posts, I'm a big fan of shorter cranks on recumbent bikes, so I swapped the front crankset for a Sugino XD600 152mm triple crankset.

Amid the modifications, I had noticed there was a great deal of room ahead of the 20" rear wheel.  Poking around online I also found other Rover builds that were sporting rear wheels up to 26".  This was just too much of a temptation not to be attempted.  As there is no rear brake needed on a tadpole trike (the left and right brake levers typically work the left and right wheel brakes rather than front and rear), the swap was an easy one.  There isn't much clearance for a large volume tire, but a 26 x 1.5" fit in the frame spacing without any trouble.
Riding was surprisingly unaffected with the exception of a bit higher top end due to the larger wheel circumference and a bit of a forward tilt that could be generally negated by adjusting the seat recline angle.  The only detriment to this configuration was that I lost the advantages of my higher volume tires.  In the end, ride quality trumped top speed and the 20" rear wheel returned home.

It wasn't long after that an interesting piece of hardware found its way to my local craigslist: an Xtracycle FreeRadical.  Xtracycle ( makes a spectacular longtail conversion system allowing a bike to become a very cool and utilitarian device - even allowing the transport of passengers on the back!  I had some experience with the Xtracycle system (will post more on that later), and instantly visions of an Xtracycle-equipped trike began dancing in my head.

The FreeRadical installation was really quite simple on the Rover and the only truly invasive part of the project was drilling a mounting hole in the Rover's frame just ahead of the rear wheel.
The system attaches in three locations - the two rear wheel dropouts and one point where the chainstays typically attach to the bottom bracket (and where a kickstand typically would be mounted) on a traditional diamond frame bike.  The location of the anchor point on the FreeRadical lined up almost perfectly with the point the chain stays attach to the main square tube frame of the Rover and simply had to be anchored to the frame in some way.  I decided the most secure (yet still reversible) mounting method would be using a bolt passed through the FreeRadical and both sides of the square frame tube.
To maximally distribute the load the Xtracycle system would exert on the frame, I used one of the brackets that came with the FreeRadical kit.  Two of these brackets can be used to sandwich the chainstays on a diamond frame, but one of them did a spectacular job of distributing the load forces and protecting the Rover's frame.

The front of the FreeRadical is designed to rest on top of the chainstay brackets (or kickstand bracket), but on the Rover this caused the Xtracycle platform to slope as well as raise the overall height of the Rover's rear assembly.  Because of these issues I chose to mount the FreeRadical underneath the frame instead.  To make sure the hardware would be equal to the task, I went down to my local hardware store and bought a nice heavy-duty Grade 8 bolt and thick washer to bear the load.
Hardware in hand, the rest of the assembly was fairly straightforward.  The two aft mounting points on the FreeRadical slid smoothly into the Rover's horizontal dropouts and the new bolt secured the system at its forward third point. 

The rear derailleur (removed prior to assembly) was relocated to the derailleur bracket on the FreeRadical, an extra handful of links was added to the Rover's loooooong chain, and a new longer rear shift cable (tandem cables are long enough) was run to the new rear derailleur position.  The rear wheel slid into the FreeRadical's dropouts and we were ready for the maiden voyage.

The first thing you notice after this type of conversion is how LONG the trike has become.  I could no longer turn the trike around in a single lane width.  It now took a full two lanes to turn this stretch limo 180 degrees.  Once the initial acclimation took hold, the ride really wasn't all that different than stock and stability wasn't affected particularly one way or the other.  One problem that became apparent a few pedal strokes in was that the chain had a tendency to rub against the chainstay when in the smaller cog and against the FreeRadical frame in the largest cog.

I found some resolution to this by adjusting the position of the rear power-side idler wheel to one of its upper mounting positions.  This didn't resolve the chain rub in the largest climbing gear, but did make downhill runs rub-free.  With the front triple crankset and small rear wheel, I found I really never needed the largest gear on the rear cassette so I "fixed" the issue by adjusting the set screw and limiting the rear derailleur's maximum range - effectively changing the rear cassette to a 8-speed configuration.  I would venture a guess that the chain rub would not have been an issue had I been using a closer spaced rear cassette rather than the wide range cluster which included the offending 32 tooth gear.
Strange noises quelled, I returned to the streets for some additional testing.  The new configuration proved very functional and usable with a few caveats.  For one, the rear shifting was not as precise as it had been prior to the conversion.  I attribute this to the many mm of additional shift cable needed to reach the rear derailleur.  A higher grade low-friction cable would most likely improve the shifting performance and return it to its former crisp shifting glory.  The second thing I found a bit unsettling was in the feel under heavy loaded conditions.  I have used the FreeRadical systems on upright bikes as a seating area for my 80-ish pound child.  Xtracycle makes a great seat cushion and foot-shaped floorboards for the FreeRadical which make it a very stable and efficient child carrier.  When my son mounted up on the back of the converted Rover I noticed a distinct amount of torsional frame flex.   As we cornered and he shifted his weight while riding I continued to notice the frame flexion.  As the Rover has a strong square-tube frame, it was not overly concerning from a structural perspective, but definitely added a bit of an odd feel to the ride.  Also, the center of gravity became markedly higher with a rear rider and necessitated greatly reduced cornering speeds.  With this type of behavior, I limited two-rider trips to short jaunts to the park rather than longer commutes in higher speed situations.

Overall the design and versatility of the TerraTrike Rover has proved admirable.  While it will never compete with the likes of its low-slung ultra-reclined brethren (think Catrike 700) from a performance perspective, it is by far the easiest to climb on for a bit of fitness, a ride around the neighborhood or a short commute.  Its seating position make it both more visible to automobile traffic and easier to see "out" of to enjoy the scenery and maintain situational awareness of traffic around you.  It really is the trike most of us SHOULD be riding even though many of us envision ourselves aboard performance trikes rocketing down the road cheating the wind and passing the roadies in their pacelines.  It all goes back to the saying that the best bike/trike is the one you actually USE; and the TerraTrike Rover is definitely in that category.

UPDATE (10/21/2011): While a cargotrike was my idea of the ultimate configuration of a Rover, my better half found she didn't agree.  Her typical trips didn't require the extensive cargo-carrying capacity of the FreeRadical, and thus the longer turning radius and increased weight were unmerited.  As I already had an Xtracycle-equipped bike that I used for errand-running and child-carrying, we had little need of a second similarly-equipped machine.  We have since removed the FreeRadical kit, returning the Rover to its shorter and more maneuverable configuration, while the standard rear rack still affords a wealth of carrying space with trunk bags and panniers.  Once again the old adage applies as the current configuration is the one that will be the most used.

Thursday, August 4, 2011

Bargain Bin Special - Huffy 626 Road Bike

A few years ago I became intrigued by the idea of drop bars.  Yes, I know, they've been around since the dark ages - but I hadn't ridden a bike with anything of the sort since I was 12.  I stopped down to my local bike shop and wandered the aisles, dazed by the number of digits in the price tags.  Not sure I wanted to be quite so committed to a style of riding I'd never experienced, I went to my next favorite store: craigslist.  $10 later I was the proud owner of a beat-up but mostly functional Huffy 626 10-speed.

A little spit and polish, some cheap bar tape and a couple tire tubes later I was off to the races.  The first thing that struck me was the aerodynamics of the drop bar position.  The second thing was that riding in the drops was not entirely comfortable for my level of flexibility (or lack thereof).  The old-school 27" wheels definitely smoothed out the road a bit nicer than the 26's I'd been riding on other bikes, and as I rode along the not-so-smooth pathways in my neighborhood I realized probably the best feature of this particular bike: the very flexible steel fork which visibly absorbed a great deal of the path imperfections.  One other feature of note on this particular machine is that the rear dropouts are slotted relatively horizontally.  This makes it easy to convert the bike over to a single speed or fixie configuration as you can use the horizontal dropouts to slide the rear wheel fore and aft to tension the chain properly.  I don't have much else good to say about that bike except it opened my eyes to new frontiers of riding.  Bad brakes, old un-true-able wheels, extremely stiff and finicky stem mounted shift levers and a creaky one-piece crank all made this bike worth every penny of the price I paid for it, but it served well as a campus commuter for a short stint.  Plus, at that price point it gave me a wonderful peace of mind knowing that I spend more at the local coffee shop in a given week than I had invested in that bike, should someone be foolish enough to steal it.

Tuesday, August 2, 2011

Evolution of a Vision R40 SWB Recumbent

For a first post on a new blog, it would seem prudent to choose a project bike that had some interesting options and results. 

I don't think any of my bikes have seen much more of a renovation than my pair of 1994 Vision R40 recumbent bikes, purchased in 2009.

The Vision R40 came in two configurations: short wheelbase and long wheelbase (sometimes called mid wheelbase).  Both have a 26" rear wheel and 16" front wheel.  One issue I had right away with the bikes was that they have the shortest wheelbase of any bike I've ever ridden (at least since I left training wheels behind)!  This makes them what you'd call "very responsive", or probably better described as "twitchy".

Interestingly enough, the short wheelbase version can be converted to a long wheelbase just by swapping the front boom for the style that has a head tube ahead of the bottom bracket.  The front fork can then be relocated to the forward position and a steering linkage ties the fork and the handlebar together.  One such longer boom was included in the box of parts that came with the pair when I purchased them, so I converted it to its longer configuration.  This made the ride much more stable at speed, and the added length smoothed out the ride noticeably as the chromoly frame soaked up the bumps.

On the whole, both bikes rode very well.  They have full mesh seats which are comfortable and extremely breathable.  Adjustable recline angle, pivoting handlebars and rackmounts make them very versatile machines.  They are on the lighter side for steel-frame recumbents, and their drivetrain is very simple and efficient with no power-side idler and only one idler wheel on the non-power side.  They can be set up as over seat steering over under seat steering, whatever your preference happens to be.

For cruising and touring the LWB seemed well-suited, but I had speed comparisons on my mind and the added weight of the boom and steering linkage seemed counter-productive... so I began working with its SWB sibling.  Handling was definitely an issue over 25mph, but nothing too worrisome - plus, I don't spend a great deal of time at that speed anyway.  What I was more concerned with was the flatland performance.  In my estimation there were a couple things working against this machine.  First, the 16" front wheel did not do very well with bumpy surfaces, and some of the trails I was riding were bumpy enough to cause me to slow measurably.  Secondly, the riding position was not terribly aerodynamic - even with the seat quite reclined.  The bottom bracket (where the front crankset resides) was just too low for the seating position and presented too much surface area to the wind. 

I decided to solve both problems with one solution - a larger front wheel.  I picked up an inexpensive steel (1" threaded) fork, had it cut to the right length, and found a used 20" front wheel that was still fairly true and rolled adequately.  This conversion was quite quick and easy as the new fork positioned the brake pads of the old brakes nicely in line with the new wheel's rim.

The new wheel definitely appeared to improve the aerodynamics by raising the bottom bracket up and bringing the pedal circle more in line with the wind shadow of the body, which hopefully would translate into lower wind resistance.  The first ride out brought about some realizations.  First of all, I'm not a tall rider at 5'6", the new wheel and fork had raised the bottom bracket height enough to make flat-footed stops and starts a bit less comfortable than they had been with the smaller wheel.  Once moving, though, the position certainly felt better.  The second observation was a pleasant one after analyzing the ride data - the bike was 5-10% faster.  Now, I could go into the comparison rides and methods, but we all know that comparing bikes to one another across days/weeks/energy levels is virtually impossibly to fully quantify.  I'll leave it to say my numbers were quite a bit improved.

This successful modification led to more theorizing on what to improve upon next.  Before I jumped into any other radical innovations, I first upgraded the drivetrain.  A new rear wheel w/ 9-speed wide-range (11-34) cassette, new 9-speed chain, new Shimano Deore rear derailleur and Shimano integrated brake/shift levers made shifting more precise while expanding the gear range (from the original 7-speed drivetrain).  I also changed out the front crankset for a Sugino XD600 triple (24-36-50) with 152mm crank arms.  I have found that my short legs prefer a shorter crankset on recumbent bikes than on diamond frame bikes.  I ride with a 165mm crankset on my road bike, but that length bothers my knees on the 'bents.  I've had good luck with the Sugino cranksets, they're moderately priced ($110-ish) and it's hard to find a wider range triple unless you customize.  I find that my speed doesn't change much with the shorter crank arms, but the comfort level is much improved.

After a number of rides under my belt with this 26/20 configuration, I once again felt the need to push the speed limits of this machine.  I first tried another size jump in front wheel diameter.  I tracked down a larger fork that would fit a 26" front wheel and swapped it out.  With the dual 26" wheels, the pedal circle moved further upward and almost fell in line with the body of the rider just as I'd hoped.  What I hadn't hoped for is as much height difference in the seating position for my short stature.  What had been a stretch to stop/start with flat feet before turned into a stretch to even reach the ground tiptoed.  On top of that, the wheel diameter was large enough that the tire actually overlapped the circle of the crank arms.  This meant that if I turned the wheel more than a few degrees while pedaling the crank arm (or my foot) would hit the front wheel.  Now, recumbent riders are generally accustomed to "heel strike" because of this positioning and it can generally be mitigated by kicking your heels out to the side when turning sharply.  Crank strike, on the other hand, is a big problem and can stop you dead in your tracks if not extremely careful.  I eased the bike out for a couple of time trial rides and found that the benefits (3-5% speed gain) didn't outweigh the drawbacks (paranoia when turning).  Time to click the "undo" button.

Back at the drawing board with the bike safely back to its 20" front wheel configuration, I decided to try another method to mitigate wind resistance: a fairing.  As luck would have it, I found a Vision Lexan or Plexi or some kind of clear plastic fairing with mounting hardware on craigslist.  It was a bit heavier than I'd imagined, but it had a lot of surface area as well.  Riding with a fairing is a bit different as vision is a bit impaired even with the clear plastic - it was a bit hard to see the pavement closer than 5 feet in front of the bike.  The fairing also made it warmer to ride - nice on a cool crisp fall morning - not so nice on a humid summer day.  Time-trial-wise, the fairing added another 5-10% to the flatland speed when the wind was light or off the nose/tail.  Cross-winds necessitated "fighting" the bike a bit because of the large surface area of the fairing and caused speeds to dip to levels at or even below those of the unfaired bike.  Climbing also slowed a bit (5-10%) with the fairing as the added weight worked against it.  None of my routes were terribly long and straight, and coupled with the midwest's proclivity for moderate-to-high winds, this was not an ideal faired bike environment.  Having not been quite as impressed with the performance gains as I'd hoped, I left the bike in the unfaired configuration for the bulk of the time unless comfort dictated its use (primarily cooler weather).

At this point I decided the unfaired 26/20 configuration of the Vision R40 was the most efficient possible while still being useable for someone of my stature.  Overall the bikes both rode wonderfully and were great recumbents.  I rode the SWB model on two long charity rides and it performed perfectly and made the trips much more comfortable than any diamond frame would have.  But, with the projects exhausted the addiction set in and I parted with the pair in search of something new to explore.