The Karver range of furling units has come a long way in the last 10-15 years, with each aspect of the design seeing incremental improvements. Captive pins with quick release mechanisms are almost universal on furling drums and swivels these days and they too have seen considerable development. The quick release mechanisms rely on small springs which can get damaged and require replacement. This blog will outline the evolution of the Karver captive pin systems and help you identify the correct replacement spring kit for your Karver furler.
In the really early days (pre 2011) the jaw pin was held in place by a simple U-Clip
The first range of Karver furlers used a traditional U-clip
Version 1
To improve speed and ease of release, Karver introduced this torsion spring system, encased in a yellow cap, which has become a key element of their design aesthetic.
These spring kits were introduced from 2011 and were standard on all Karver furlers until early 2018 and are the most common type in circulation. The release mechanism relies on a small string attached to the spring which is the easiest way to tell you have a V1 Spring kit.
Version 2
The Springs in the V1 quick release mechanism are prone to damage. In an effort to improve the robustness of the design, Karver introduced their V2 kits in 2018. This time they turned the plastic cap itself into a button, which moves in a vertical plane on a compression spring,
Version 3
Hot on the heels of the V2 comes the V3 design which is being introduced gradually over the next 6-9 month. This is a natural evolution of the V2 and rather than the whole plastic cap moving, the cap is fixed and they have added a central stainless button. This should again provide further improves to durability and reliability
These spring kits are NOT INTERCHANGEABLE or upgradable – you must have the correct spring kit for your furler. Therefore, when ordering a replacement, it is essential that you order the correct version. In general, furling units bought between 2011-2017 and have a yellow string-pull will be V1. Furlers bought between 2018-2020 where the plastic end cap moves vertically are V2 and ongoing, new units will be V3.
A KF 0.9 Furler with the V2 spring system
Spring kits are also sized according to the unit – so when ordering you need to know the size of your furler and the spring kit version. E.g. KF2 Spring Kit V1.
Finally, a very important point to note is that the latest 3:1 Quick Release Sheaves ALWAYS have a spring kit one size down from the furler. So a KF2 3:1 QR Sheave takes a KF1 Spring kit.
If you have any questions about individual parts, please feel free to email us at support@upffront.com, or click the link below to see our full range: