In what might be the upgrade to end all upgrades, CeramicSpeed just released two new off-road editions to its line of Oversized Pulley Wheel X Systems (OSPW X), for Shimano's GRX group set and the 12-speed Deore XT and XTR group sets. CeramicSpeed don't do things by halves, which we tested some of their bearings in 2018 it was obvious that they're designed to squeeze every last piece of performance out of them.

Those same bearings and bottom bracket are still rolling smoothly to this day.

The OSPW X is designed for extreme durability and to optimise drivetrain efficiency with low-friction bearings. The new OSPW X System offering for Shimano XT/XTR 1x12 from CeramicSpeed incorporates a custom symmetrical 14-tooth upper and 18-tooth lower pulley profile. Specifically designed for the rigours of mountain biking, they ensure stable chain retention without any additional drag.

Show me the #facts about the gains available with oversize pulley systems.

Designed for 12-speed cassettes ranging up to 10-51, it comes complete with two tension springs for customisable setups on varied terrain. CeramicSpeed already had a OSPW X model for SRAM Eagle drivetrains, so this addition is a bonus for those riders on Shimano 12-speed who really want to find the small gains that can all add up. Do you need it? No. Will some people want it? Most likely!

CeramicSpeed's OSPW Systems is claimed to offer improved efficiencies and reduced friction of 35-40% over traditional stock pulley configurations. It's a combination not just of oversized pulleys, but their bearings as well. 

All offerings in the OSPW X category come in an aluminum pulley wheel design with a custom-molded carbon fiber cage and ensure lightweight durability. Available with both standard and coated CeramicSpeed bearings, the systems are designed to withstand the corrosive factors of the off-road conditions, being covered by a warranty program of up to 6 years. Pricing starts at €499, which ius about $850. Yep, that's a lot of coin!

If you have tuned your bike to the finest detail and lowest weight and not yet thought about lowering resistance in your drivetrain and bearings - that's the next step. There are great cumulative gains to be made with the right chain, chain lube, and bearings. Getting them wrong could be sapping at least 20W, although the gains available with the OSPW X are barely 10 percent of that. This sort of fine tuning isn't for everyone, but there are some of us who are searching for everything that's needed to make things better. Even if it's a marginal gain for a significant cost. If that's you - then chances are you'll like CeramicSpeed products.