coil springs for rock shox judy
When had been doing my last restoration of the 1996 Rock Shox Judy fork I`ve realized a serious fact - missing coil springs on the market. It`s really strange that it`s almost impossible - today - to find any of them (right, if you`re lucky enough you may find - from time to time - rare Kronos or White Bros springs, but not too many). Does it seem that the coil springs after-market is currently empty? Well, it might be true. This observation led me to think about custom springs for Judy forks.
During last months I did some measurements and calculations, as well as I got in touch with a company, here in Slovakia, that regularly produces various coil springs for many engineering deployments. I showed them my blue-print of the springs for Judy forks and they produced a few - experimental - pairs of them in custom production. I decided to use stainless steel wire (that allowed us to keep the wire unprotected by any painting, just for this reason of experiment). To be as close to former after-market products as possible, we`ve made the same number of spring threads and length. I didn`t have precise measurements for spring rates of different weight riders (like "soft", "medium" and "firm"), therefore I firstly decided to make a set of springs for my current rider weight, which is around 73 - 75kg in high season (so I can say "medium" ride firmness). Once a set of custom springs were done, I prepared a blue-print for spring end-caps used to properly match the springs on top of the shafts in the fork. I made it easy from aluminium and it fits perfectly the inner and outer diameter of the springs. Again, due to same reason as above, I kept the end-caps without any painting or anodization, however, when needed, I can make any standard colour anodization.
The springs fit perfectly Rock Shox Judy model years of 1995, 1996 and 1997. I installed the springs in my spare 1996 Rock Shox Judy XC fork. Because the wire used to make the springs is a bit thicker, I cut off some outer material from the springs to get them easily into plastic adjuster top-caps. The springs work together with a 63mm damping cartridge. All works well, but I have to note that additional 2mm plastic shim (e.g. plastic "jax" connector for MCU elastomers) have been required, because the springs are 2mm shorter :)