Fork coatings are primarily done to lower the friction between the main and dust seal and the fork tube, but also aid with the durability of the fork and longevity of the seals.
The two most popular coat types are Titanium Nitride (TiN) and Titanium Carbonitride (TiCN). TiN usually finishes in a gold color and TiCN comes out looking like a blue-grey.
Both are coatings that are applied in a high-heat vacuum camber and therefore can only be done on steel.
TiN and TiCN are very common coatings used on drill and machine bits to increase the longevity and lubrication needs of the bits.
Many suspension shops offer the
service of coating your forks with either of the two options, which means they disassemble the aluminum casting that is screwed on the bottom of the fork, and then ship the tube out to a shop that has the necessary chamber. Cost is about $250 to $400 for a pair depending on where you go.
In many cases, you can go directly to a coating shop and save a lot of money but you have to manage the process and break down your own forks. And some shops will take your business, but may not be fully capable of providing an even and well-adhered coat so you have to be cautious of what they are able to offer.
The castings on the bottom of the fork take some work to get off, but if done correctly, can be pulled and re-installed with no concerns.
My intention was not to talk anybody into this. I just thought if someone was ready to go that I would bundle the job together. That's it.
Overall, I wouldn't bother unless it really means something to you.
DaveJ