INTO THE RIDE #40
A PERFORMANCE TANDEM
by Randy Schlitter
The cold air whipped us, our cruising speed helping it sink into our skin, cheeks turning fiery red. I was thinking my son has character to help the old man test on a day like this. We crunched up the hill; I was amazed at his strong legs, and answered with a stepped up effort. I always preach “don’t climb a hill at the bottom, save something for the top”, it seemed the lesson was not in my stoker’s mind, as we kept holding our speed, maybe even increasing. It felt good, and it was about time, we were finally getting this beast dialed in, a new recumbent tandem, which at this point was an unsightly prototype, not even worthy of paint. Chances were good this frame would end up hacked up for scrap. Yet this unsightly machine was starting to produce results, and I smiled openly as we now gained speed on the flat. The wind becoming less a chill as the warm fuzzy feeling about this prototype increased.
The road to a good bike is not always a single sweep effort. Past experience with developing the Screamer was also a multiple prototype event. But we do learn in time, and the Seavo (pronounced see-vo) was dialed in by frame number 2; an improvement over the Screamer program by a factor of 2.
What makes this bike special is the performance orientation. Just the stance of the bike alone suggests a more aggressive attitude; it is an effective fusion of short and long wheelbase geometry. The better aero position of the captain and the shallower angle to the crank for the stoker make up the most apparent change over the Screamer. But a few more design aspects enter the picture.
In a glance the dual 26” wheels set the machine apart. Choices abound in wheels sets, something that is always welcome when trying to tailor a design to a broad spectrum of need. In this case we chose a pair of disc compatible AeroHeat Velocitys. They are tough, light, and are smooth rolling. There is a large selection of tires for 26” wheels, and frame clearance for 2.3 widths. The stock Seavo rides excellent with the 1.5 Primo Comets.
The instant you begin pedaling you will feel the big wheel effect. It translates into good handling and easy-to-hold speed. An important bonus is safety; the large wheel has much better chances of maintaining control over less-than-ideal roads.
Standard MTB Fork
By setting up the frame to accept standard tandem MTB forks, those choosing a frame set will have more choices. To those building up a Seavo from a frameset: make sure if you switch out the provided fork, it is rated for tandem use. The most popular choice will be a shock fork option. We may offer such in the future, but for now the custom alloy fork will be stock.
Adjustable Seat Pan Angle
This is a double benefit; you can custom tune the seat pan angle to your body, then once off the bike, can be folded flat for transport. How important is an adjustable seat pan? The Zephyr seat has proven popular partly because of this feature, rider feedback sees this feature as more important than they realized. I think in time it should, if possible, be a feature most seats should have. Carbon pans are also a nice way to cut weight, and are standard on the Seavo.
Lighter Frame Improved Geometry
The Seavo becomes a lighter frame from the “Y” type chain stay, and thinner wall tubes used in the stay. It retains tremendous strength in both torsion and beam resulting in good acceleration and less energy to maintain cruise. Hand crafted using TIG welding and top grade 4130 tubing, the Seavo frame is warranted for life, and should look fresh for many years with the durable powder coat finish.
Geometry of the new frame fits more people. In fact we currently offer it as a one size fits all, and there seems to be little lost to this. The worst case is a short captain, which is not the common case. Instead couples using Screamers have wished for a lower seat height and less X-seam for the stoker. The new frame provides exactly that, but does well to fit two larger riders also. Of course there will be the odd tandem crew that will not fit the Seavo, but the greater demographic is covered well.
Idlers can make or break a well-laid-out recumbent. The Seavo’s idlers impede as little as possible. The timing chain idler system is a broad departure from the Screamer. It is very simple to adjust and has proven to be trouble free. The intent was to make it stout enough to withstand the odd circumstance a tandem imposes on idlers and timing chains. Sometimes a high load on the free side is applied by a rear stoker overpowering the captain. Having a dual set of idlers handles this load very well, and as an added bonus remains fairly quiet throughout.
The cruise speed will impress you, but without great stopping power how safe is that? Dual 203 disc brakes plus a rim drag brake provide responsive stopping power. The stoker controls the drag brake from the left side of the stoker seat.
The Seavo is offered in several colors, sports a nice grade of gear throughout, and has several unique features, making it an exciting choice for the tandem inclined. How the Seavo compares to the venerable Screamer will surely be debated, but our desire to push the envelope of tandem recumbent design should never be diminutive due to already having a successful design. To create better products often a bold stroke is required, and the Seavo fits well into the niche of such effort. Until next month ride safe and stay into the ride!
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