The most common questions we get asked about Oversized Pulley Wheel Systems

CeramicSpeed OSPW System FAQs

Watch as we answer the most frequently asked questions about our CeramicSpeed OSPW System - or read the questions and answers below.

The Benefits of Narrow Wide Pulley Wheel Tooth Profile

CeramicSpeed OSPW System compatibility

CeramicSpeed has developed a broad range of OSPW Systems to fit most modern road and mountain bike derailleurs from Shimano, SRAM and Campagnolo. Please see compatibility chart for a comprehensive listing.

Do I need a new chain if I install the OSPW System?

Due to the oversized pulley wheels and the need for a longer chain, we recommend starting with a new, uncut chain. We do not recommend adding additional links to an existing chain. Please check the OSPW Chain Guide for more information. 

Is a standard chain long enough or should I buy a special long chain?

A standard chain will be long enough to fit the new OSPW System. You will need to remove fewer, if any, links when installing a new standard chain.

How does the CeramicSpeed OSPW System differentiate from other systems with big pulley wheels?

The CeramicSpeed OSPW System has been proven to be the fastest pulley system in the world, and for good reason. No pulley wheel system on the market today has been tested to provide the same energy savings, between 30% and 60%, as the CeramicSpeed OSPW System. The energy savings found in our unique OSPW Systems are a result of sleek design, high-quality materials, a tested and verified understanding of the impact spring tension and chain length on efficiency, along with two high precision aluminium pulley wheels that carry CeramicSpeed Bearings.

Has the frictional data been verified by an independent third party lab?

The OSPW System has been put through extensive road and laboratory testing, both in-house and in collaboration with third parties during exstencive development from 2013 through the launch of our first OSPW System in 2015. Former American independent test laboratory, Friction Facts, had been used to test friction performance of the OSPW System (Friction Facts was acquired by CeramicSpeed November 2016). The tests conducted by Friction Facts have seen the OSPW system go up against the most commonly used stock pulley wheels, test runs have been performed making use of a new chain and a 'typically seen' dirty chain. Tests have been made at 95 RPM in 53/12 gear, using a Reactive Torque Pulley Tester (RTPT).

Will the CeramicSpeed UFO Chain work with the OSPW System?

The CeramicSpeed UFO Chains are compatible with the OSPW System and will help you save an additional 2-5 watts, or over 40% more effcient than a traditionally lubricated chain.

Does the OSPW System work for MTB?

In 2019, CeramicSpeed launched the first dedicated off-road OSPW X System for SRAM Force 1X derailleurs. Through continued development there are also OSPW X systems for Shimano RX800/805, SRAM Eagle, and SRAM Eagle AXS derailleurs.

What size cassette can I use with the OSPW System?

This will vary depending on the derailleur model, but in all cases the Oversize Pulley Wheel System equals or exceeds the factory maximum cassette size. Specific compatibilities can be found here.

Where can I purchase?

The OSPW System is available for purchase through all CeramicSpeed dealers worldwide and via the CeramicSpeed webshop.

How does the OSPW System affect the performance when changing the spring tension between High and Low?

When using the highest spring tension setting your energy savings using the OSPW System starts at 30%-60%. When changing to the lower spring tension the energy savings will increase, however, lower spring tension might affect gear shifting performance so please test thoroughly.

Does the OSPW System for Shimano work with Di2 and 9100/9150?

Yes, the OSPW System works with Di2 11s and 10s gear groups.

For Shimano 9100/9150 we have developed a special System, designed to fit the Shimano derailleur, featuring 13/19-tooth combination.

Does the OSPW System compromise the shifting performance?

No. One of the main focuses during the development of the OSPW System has been to maintain factory shifting performance.

How durable is the OSPW System?

The CeramicSpeed OSPW Systems have all been tested and proven on the harshest testing grounds. The OSPW systems we sell to consumers are identical to the systems we supply to professional athletes and have been tested in the Tour de France, Paris Roubaix, Strada Bianche, World Cyclocross championships, Dirty Kanza, and many other events around the world. When correct chain length, spring tension, and derailleur alignment are in place, the durability of the OSPW systems are inline with stock equipment.

How long does the OSPW System last? Is it something I just put on for racing?

The OSPW System is suited for use in both training and racing environments. We recommend that the system is continuously used to minimize potential damage through removal & repeated installation. The OSPW System is equipped with the same high-quality CeramicSpeed Bearings as all our other products, resulting in your OSPW System spinning just as fast many years from now. The cage, pulleys and hardware are all made of high-quality materials; carbon reinforced polyamide, aluminium and titanium. The OSPW System is covered by the CeramicSpeed warranty program: 4 years warranty in the standard bearing version and 6 years in the coated version.

How much does the OSPW System weigh?

Thanks to the lightweight materials used, the OSPW System weighs approx. 70 g, making the difference between a standard rear derailleur pulley system and the CeramicSpeed OSPW System negligible. The small addition to the weight is not a compromise to your bike performance thanks to the overall capabilities of the system.

What are the aerodynamic advantages of the system?

The CeramicSpeed OSPW system has been tested in two separate wind tunnels, one in Scandinavia and one in North America. No measurable aero loss has been recorded on the system. At certain yaw angles, the system recorded a positive sail effect when running with a certain depth of wheel.

Will the OSPW System fit in a bike travel bag?

Most often you will have to dismount the entire rear derailleur when travelling. Use an Allen Key to remove the derailleur when packing the bike, and reinstall it before use. Most bike travel bags do not allow the space or protection for the rear derailleur with the OSPW System in place on the bike.