Wear-Resistant Bearings Reduce Weight and Increase Rigidity in the Rear Frame

Profile

• What was needed: Plain bearings as a replacement for metallic deep groove ball bearings on the lower rocker of the DW-link on the rear frame  
• Requirements: Wear resistance, insensitivity to dirt, moisture and vibration, freedom from maintenance, lightweight
• Application areas: Bicycle industry, mountain bike components, full suspension frame construction

The Californian mountain bike manufacturer ibis has been using plain bearings from igus in its full suspension mountain bikes since 2013. They were first used in the original model of the Ripley trail bike, but are now used in all ibis full suspension frames.

Photo: ibis Cycles

Problem

As in all articulated links, ibis had originally fitted sealed cartridge ball bearings on the lower rocker of the DW-link rear frame. "It was what the customer always wanted", explains Colin Hughes, lead engineer for ibis. "But some of our highest load pivots moved less than 20 degrees. It did not seem to matter how high the quality of a ball bearing I specified. It would always start feeling notchy prematurely." So it made sense to change over to plain bearings as, in the case of small rotations, they are better able to cope with large forces than rolling bearings.

Solution

ibis decided in favour of iglidur plain bearings. They saved 80g of weight compared to their predecessors, increased rigidity and reduced maintenance to zero thanks to dry operation. The most important criterion for the changeover, however, was the improved durability: "After the first year when the new frames with igus bearings were on the market, I received feedback from customers who had disassembled their frames for maintenance", recalls Hughes. He got a few from Great Britain, where the owners were amazed at how well the bearings are holding up. "I think our latest developments have proven their worth, as our frames are some of the lightest and stiffest available. We will certainly see more companies using igus bearings to stay competitive."

Robin Wallner has been riding for the ibis Enduro Racing Team since 2014. In 2019, he came 11th in the world rankings of the Enduro World Series. In 2018, he had his best year ever: recording three Top 10 finishes in the EWS and, at one point, occupied second place in the world rankings before a broken hand ended his season.
 
As a veteran rider, Wallner is particularly attuned to his bike. When ibis started the changeover to igus® components, he was initially sceptical. "I had some concerns that plastic wasn’t going to hold up against the forces that we put on our bikes", recalls Wallner. "I wasn’t sure how it would withstand the abuse of dirt, water and other bike path debris."

But since switching over to iglide® bushings, his Ripmo V2 has proven to be extremely robust in difficult mountain terrain. "In over two years of riding, our Enduro Team hasn’t broken any bushings", says Wallner. "They have definitely been holding together better than I originally thought. They are also lighter and much easier to maintain than the bushings I previously used."
 
Wallner is one of the world's very best bike riders, at whom development is actually aimed. "All mountain biking technology is developed for use in racing, with speed in mind", says Matt Floyd, igus® sales manager for the west region of the USA. "Most of the technology, however, is used by recreation cyclists." And they will also be pleased if lighter bearings that have a long service life and do not have to be maintained are used in the bike.

Photos: ibis Cycles, igus GmbH