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Suspension Coatings -What’s the Real Deal?

Stillwell Performance

You have probably cruised the pits at a National and saw the trick looking fork legs on your favorite factory rider’s bike. You might have thought they were just another “unobtanium” part that the factory spent thousands on in their quest for a #1 plate.

But you might be surprised to find out just how effective these coatings are-and how affordable they have become.

A bit of history-when coatings were first used by the factory teams, they were almost exclusively Titanium Nitride (Ti), a very hard ceramic material that is applied to the metal surfaces of the fork tubes and shock shaft via a physical vapor deposition process. This material covered the surface in a very thin film and was effective at reducing the friction created by the fork/shock moving through the suspension stroke.

The downside to this particular process was that it was very brittle, and could crack and flake off if subjected to bending or stress.

Enter DLC, or Diamond Like Carbon. This material is applied in a similar way as Titanium Nitrite, but because of it’s makeup it flexes when subjected to stress, like pounding through the rocks or when your buddy T-bones your front wheel.

DLC has a wear factor that is 300 times (!) less than steel and 10 times less that Ti. This makes it ideal for the tough environment dirt bikes face.

Having the coating applied is a straightforward process. You will need to disassemble the fork tubes and remove the fork axle lugs. Some brands have small set screws in the fork lug that need to be backed off for removal. All forks have the tube loctited to the lug, and the lug will need to be heated to remove.

The shock shaft requires disassembly from the bottom clevis. As with the fork lug, the clevis is loctited to the shaft and needs to be heated prior to removal. Once the shaft is removed, you will need to pull the rebound assembly from the shaft.

If this process sounds too complicated, contact a reputable suspension tuner to perform the work. Make sure to ask questions about the tuners experience with this procedure, as there are delicate o-rings in the fork lugs and shock shaft. Too much heat applied at the wrong time can cause big problems. Also, valving and tuning with DLC is different than standard forks/shocks. Check to see what experience the tuner has.

When DLC coatings are combined with the right spring rates and valving, you end up with world-class suspension.

It is important to note that valving & tuning can be different when using coatings. The reduction in friction results in parts that move easier, and faster. Changes in valving must take this into consideration. In general, rebound is faster with coatings as the spring force encounters less resistance. In some cases, we have even altered spring rates to take advantage of the smooth, “works” like feeling DLC gives the bike.

We have significant experience with DLC and tuning for maximum performance. Give us a call at the shop with your questions, we will be happy to talk about your specifics.

Thanks, and keep it pinned!

Alan Stillwell

Stillwell Performance

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