Note: this model is no longer available. However, service parts can still be purchased
These bikes come with completely stepless gearing system and roller ramp free-wheel clutch.
The Thys 222 CVT is equipped with:
- Stepless gearing system.
- Large gearing ratio (Snek diameter varying from 178 to 40 mm).
- Thys rear hub with roller ramp freewheel clutch that guarantees instant grip.
- Bend steering bar for better aerodynamics.
- Improved Cro-Mo tubing for frame and bowsprit tubes.
The CVT system: (Continuous Variable Transmission)
The “lower gear” solution: to create a larger and lower gear range I had to change the system of shifting. This alternative configuration shifts by rolling the cable further on or off the Snek. The cable is now attached with one end to the smallest part of the Snek (left picture).
By rolling it off you’ll move to the higher gear (middle picture), while rolling it on, moves the cable into a lower gear (right picture). This system enables you to increase the diameter of the snek as much as you want, shifting is no longer limited by the length of your stroke.
How the system that is now standard for THYS 222 CVT and THYS 240 rowingbikes works: there is a unlockable clamping device at the foot slider (picture) that attaches the propulsion cable to the foot slider.
When shifting, right thumb button, hereinafter referred to as clutch lever, is pushed all the way and thereby two things happen: the Snek is locked (picture), it can no longer turn around its axis and the propulsion cable is unlocked from the foot slider.
When this clutch lever is pushed:
- making (a small part of) a stroke is shifting down
- making a (part of) a recovery stroke is shifting up
Push the clutch lever all the way, or not at all! There’s no way in between!
So one end of the propulsion cable is attached to the smallest part of the Snek, it is winded more or less over the Snek.
So one end of the propulsion cable is attached to the smallest part of the Snek, it is winded more or less over the Snek. Then it goes through the clamping device at the foot slider, to the bow pulley that also works as cable tensioner (picture 12). After that the cable goes to the (not yet) used part of the Snek and is winded on the Snek all the way to the largest part of the Snek where the other cable end is attached to the Snek (picture 13). This shifting mechanism is very easy to operate and it is completely stepless.
The clamping system at the foot slider uses two hardened steel wedges to clamp the cable. The lifetime of the wedges is estimated at at least 5000 km. Just like the propulsion cable the wedges are very easy to replace and not very expensive. With the standard CVT Snek (178/40 mm) your range of speed goes from 4 to 70 km/h. So this Snek is also suited for alpine use.
The bow sprit incorporates an indicator of the gear you’re in (low to high on photos).
The lifetime of the propulsion cable and Snek of the CVT system are at least twice as long as on the earlier Snek shifting system on the “regular” 222.
Thys guarantees that the lifetime of the CVT cable is at least 1500 km and the Snek lasts at least 8000 km. In reality much longer values have already been realised, certainly in Alpine use! In case heavy rowers succeed to create faster wear as stated above they are strongly advised to start racing with their rowingbikes!
Besides the racing advice THIJS I.D. will give them a discount on new CVT cable and Snek at the same percentage discount as the lifetime was under the above mentioned limits.
The CVT clamping system works best with the original, specially made, CVT cable. As alternative a standard water sport steel cable Ø3,2 mm ( 7x 19) can be used. This 1/8 ” size is not easy to find in Europe but can be (mail) ordered at Thys. In emergencies a standard water sport cable Ø 3,0 (7 x19) can be used. It can happen that this thinner cable does not declamp as easy as the 3,2 mm cable does.