This tandem is one of DaVinci’s Joint Ventures. The Joint Venture is available in steel, aluminum, titanium, or carbon fiber. Ours is a steel version, and has a beautifully hand-made frame, and all top-tier parts. The tubing is custom drawn, oversized, and multi-butted Reynolds Cromoly steel.
A great red paint job. This Joint Venture is a 700c wheeled version, but 26″ wheels are an option as well.
The Joint Venture comes with a Cane Creek Thudbuster suspension seatpost, and has a unique setup of Campagnolo Chorus shifters operating a modified SRAM X.9 rear derailler. This drivetrain is different, but it results in the best-shifting tandem I’ve ever worked on. The Campag “micro-click” front shifter also allows for Davinci to build the Joint Venture with four chainrings! This bike is a 4×9, or 36 speed, bike … and shifts like a dream!
Here is a good shot of the White Industries rear tandem hub. It is a 40 hole tandem hub with the special 145mm width, and can hold a rotor for the disc brake.
The most unique feature of DaVinci tandems is their excellent invention, the ICS drivetrain. The picture to the left shows the ICS. The ICS (Independent Coasting System) lets each rider pedal or coast when they want to, regardless of what the other rider is doing. So you can drink when you need to, adjust your seating when you need to, or rest when you need to. It is a great feature to help a newer bike rider feel comfortable on a tandem.
Technically, the ICS is simpler than it looks. The timing chain (on the right side of the bike) is simply separated into two smaller chains, each going around a standard single speed freewheel cog. With each rider’s timing chain section running around it’s own cog, coasting becomes independent.
We’ve never had anyone request eliminating the ICS, but if you do want to, the two freewheeling cogs can simply (and cheaply) be replaced with two fixed cogs.
It is a very cool system, and is very reliable and shifts great!