SKF’s two-wheeler segment is only 10 years old and was developed because one of their employees was an avid moto rider. He wanted a smoother seal so his fork would work better and be more sensitive to small bumps, which would reduce vibrations at the bar. It took a couple years of development, but it yielded a self-lubricating compound that reduced friction on the stanchions without compromising seal quality or longevity.
Those products started as aftermarket upgrades, then moved into OEM placements. Then, in 2012, their seals started showing up as OEM on Fox mountain bike suspension. Since then, they’ve become OEM spec on high end forks from most every major MTB suspension brand, including Fox, Rockshox, DT Swiss, Ohlins and more. And not just the external wipers, they may also be on internal damping cartridge seals.
Now, they’re developing special condition add-on seals called Mud Scrapers that can wrap around your seals and holds in place with a cotter pin. The idea is to add an extra layer of protection against mud and larger dirt particles when needed, and be easy to remove when not. They’ve offered these for moto forks for a while, and are now prototyping and testing them for mountain bikes, too.
They’re also working on a new floating piston seal for prior generation Rockshox Reverb dropper posts, which may be something you’ll see show up in rebuild kits. This part integrates seven components into a single piece and improves seal performance where it separates air from oil.
Another cool thing they’re working on is an IFP that replaces the multi-piece design currently used. Common designs are a metal piston with a rubber O-ring, which tends to have a lot of stiction. So they’ve developed a single-element seal made of their proprietary material with a dual-lip seal design. It seals just as well, has less friction, and it has built-in flexibility. That last feature provides better small bump sensitivity that mimics what you’d find in shocks using a bladder-based IFP, but without the permeability issues those can have. They’re already using this design in motocross shocks, but are developing them for mountain bike products, too. (Read our Suspension Tech Series to learn what an IFP is and how they work)
Lastly, they’re making a bigger push for riders to do more frequent service. And by more frequent, they mean at least once per season. The kits will come with the seals, pre-lubricated foam rings and all the small parts needed to replace your seals (you’ll still need to buy whatever oil your fork recommends using in the lowers). An iOS app helps you find the right seal for your bike, then their tutorial video walks you through the process, which is easier than you think. They make service kits for most brands and models, retail is around $28. They’ll soon be offering a new tool (the big green thing on the right in the top photo) specifically designed for pressing the seals into place, which has an inner cylinder to help guide the seals in straight. Home mechanics, you can also use a PVC pipe that fits over the seal and only presses on the thicker outer flange…you don’t want to press on the thinner wiper part to install it.
