coil springs for rock shox judy
When I had been doing my last restoration of the 1996 Rock Shox Judy fork I 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 are currently empty? Well, it might be true. This observation led me to think about custom springs for Judy forks.
During the 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 blueprint 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 from any painting, just for this reason for the experiment). To be as close to former after-market products as possible, we`ve made the same number of spring threads and lengths. I didn`t have precise measurements for spring rates of different weight riders (like "soft", "medium" and "firm"), therefore I first 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 with the inner and outer diameter of the springs. Again, due to the 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 the 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 an additional 2mm plastic shim (e.g. plastic "jax" connector for MCU elastomers) has been required because the springs are 2mm shorter :)