Trek BB90 Shimano WS2 Coated Bearings

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The need-to-knows for the Trek BB90 Shimano bearings with WS2 coating.

BB90 is the road bike version of Trek's proprietary Direct-in-frame bottom bracket system. No cups or extra hardware required. Bearings press directly into the frame. These Trek BB90 Shimano bearings with a WS2 coating will work with all Shimano HollowTech crank systems.

How do you improve the performance of the highest performance BB90 bottom bracket on the market? Easy, ask a rocket scientist.

Tungsten Disulfide (WS2) is an industrial aerospace coating technology developed by NASA to improve the durability and performance of complex mechanical systems aboard everything from the International Space Station to probes that mapped the surface of Mars.

With an astounding dynamic coefficient of just .030 when applied to the steel race components of our Ceramitech bearings, the WS2 coating on our Trek BB90 Shimano bearings significantly improves performance with mind-bending savings of 3-5 watts in most applications.

Our WS2 coating accomplishes these incredible gains by adding a permanent lubricating layer to the steel races while increasing surface hardness to from 67Rc to 70Rc to eliminate the excessive wear, seizing, galling, and fretting typically associated with ceramic ball on steel race relationships.

An incredible increase in spin performance AND durability from a high-tech coating that’s just 0.00002" thick! What can we say? The WS2 coating on our Trek BB90 Shimano bearings is just another reminder that we are living in the future right now. For a more intensely technical experience regarding our WS2 coating technology, please visit our WS2 Tech page.

Our zero-drag bearing shields are included with your purchase.

How do I know if my bike needs a Repair Kit or a Standard Kit?

If a bearing or both bearings are loose in the frame bottom bracket shell while you are riding and/or can be installed or removed by hand with little effort when the crank has been removed from the bike, you need our REPAIR KIT.

If the bearings are snug in your frame’s bottom bracket shell, and you need to knock the bearings out mechanically, and need to use a press to install the bearings, order our STANDARD KIT.

What’s the difference between a BB90 Repair Kit and the BB90 Standard Kit?

Short Answer:

The Standard Kit uses VibraTite530 while the Repair Kit uses VibraTite538. Both of these compounds secure the Trek BB90 Shimano bearings in place during use while allowing for simple removal and servicing by standard means when necessary and DO NOT have any effect on your frame’s warranty whatsoever. The 530 works better in tight spots while the 538 works best with a looser fit, so please order the correct kit for the best results.

Long Answer:

Many manufacturers, including Trek itself, are marketing “0.1mm oversize bearings” as a solution to the problem of bearing creak and bearing retention in Trek frames with bottom bracket bearing socket wear and for frames Trek admits might have a manufacturing variance that effects bearing fit. Either way, there is no way to know if their 0.1mm oversize is big enough or, as will be the case for most bikes, is actually way too big. Believe us when we say that 0.1mm is gigantic. Isn’t bigger a good thing? Answer: Only if it’s the right size, because bearings that fit too tight will not run smoothly, in many cases barely turning, and this means not just wattage-sucking, dismal performance, but a drastic reduction in bearing service life.

This is why we only use high-quality, standard size Trek BB90 Shimano bearings with the right retaining compound and hardware to solve problems with these specific bikes.

Note: Use appropriate bike bottom bracket tools for your installation and service needs.


Bottom Bracket Selection Guide