The Four by 4 Linkage is our unique and patent pending secondary four bar linkage designed to alleviate many common issues with current full suspension frames.

The Solution : Knolly's patent pending Four by 4 Linkage:

The Four by 4 Linkage came out of our design goals to design a frame that had the pedaling, braking and handling characteristics that we wanted, while at the same time eliminating the annoyances that bugged us with current frame designs.

The Four by 4 Linkage isn't just a secondary four bar linkage – it is a formula on how to design and build a full suspension frame that incorporates rear wheel path, seat tube placement, shock placement, seat clearance (for those technical moves), rear end lateral rigidity, climbing geometry and other aspects into a frame's design.

Benefits:

The Four by 4 Linkage allows us the freedom to solve these problems:
  • Stand over height and continuous seat tube: by keeping longer stroke shocks “horizontal”, we can keep the top tube height low. By using a continuous seat tube with a fully adjustable seat post, when the seat is completely lowered a rider can straddle the seat comfortably (for additional information, see our section on small riders).
  • Seat position: When the seat is extended in a climbing position, the lay-back seat tube intersects the location of a normal 72 or 73 degree seat tube angle, ensuring proper climbing geometry. When lowered, the seat is slightly more forwards giving more room for rear tire clearance as well as making it easier to get behind the saddle when riding technical terrain.
  • Rear shock and leverage ratios: by keeping the shock roughly “horizontal” on our longer travel frames, long stroke shocks can be used, ensuring our leverage ratios are well below 3:1. Lower leverage ratios increase shock sensitivity, bottom out resistance and reliability. The secondary linkage also isolates the shock from side loading and places it in a location free from tire roost, further increasing its reliability.
  • Rear shock accessibility: having the rear shock accessible in the front triangle means that it's quick to adjust, tune, maintain and remove the rear shock.
  • High lateral rigidity: by keeping all wheel path suspension components at the back of the frame (i.e. not being forced to bring pivots forward of the seat tube), we can keep linkage elements as short as possible, increasing their lateral rigidity.
  • Tire clearance: by using our lay back seat tube design so that tires won't hit the back of the seat tube (or bottom of the seat) when under full compression, our frames feature excellent tire clearance.
  • Neutral braking: Knolly frames are active under braking forces ensuring maximum traction in difficult sections
  • Neutral pedaling: our wheel paths are tailored so that our frames have efficient pedaling characteristics. While a V-tach will never climb like a lightweight XC bike, you CAN pedal it to the top of your favourite trail.
  • Minimal chain growth ensures that our frames are free from annoying pedal feed back.
The problems with current technology:

When we first started designing the V-tach, we looked at the existing suspension designs in the market and found that they had various annoyances which would not meet our design goals. Common problems include:

  • Interrupted seat tubes and the tall seat tube masts that they sometimes create
  • Rocker links that hit seat post quick releases on smaller sized frames or lowered seats
  • Tires that hit the back of the seat tube or the seat under full compression
  • Difficult to access rear shocks (frankly a pain in the butt with today's pressurized air and volume adjusting anti-bottoming shocks with multiple adjustments)
  • Lack of rear tire clearance
  • Lack of lateral rigidity – especially on multi-pivot linkage frames and frames with long chain stays and seat stays that extend past the seat tube
  • Limited stand over height where it really matters. This is especially important for smaller riders where being able to fully drop the seat to a very low height so that they can put their feet on the ground while straddling the seat is key (see our section on how our frame designs benefit smaller riders here)
  • Artificially long chain stays that try and address some of the tire interference problems: this is fine for DH frames, but reduces “flickability”, climbing ability and low speed maneuverability for long travel free ride frames
  • High leverage suspension ratios that reduce rear shock performance and reliability
Copyright Knolly Bikes 2008. Web Development by Veratta. Design by ItalicPixel. Sitemap