Thanks to Two Wheel Drive for the use of tools and shop space, as well as for providing expertise and repair parts.
I’ve kept away from suspension forks for a long time. Part frugality and part aesthetic rigidity, there have also been some real concerns that a suspension fork is not prudent for “the long haul”. Enter: Lael’s secondhand Reba fork, acquired last fall before embarking upon the Colorado Trail. Re-enter: memories of my early 2000′s Gary Fisher Tassajara with tight mountain bike geometry and a Rock Shox Pilot suspension fork. Expect: a summer of trail riding in diverse conditions all over Europe. In the past, I have argued for the utility of a fatbike for diverse and rugged conditions. In the same vein, I plan on taking a true mountain bike to Europe– a steel Raleigh XXIX 29er with a suspension fork. The right tools will allow the full realization of an idea. A suspension fork may be the right tool.
I removed the lowers from Lael’s Rock Shox Reba fork and replaced the dust wiper seals and lubricating foam rings. All parts were cleaned, degreased and regressed. This is no more challenging than repacking a loose ball bearing hub. This reduces some of the mystery of the fork, and inspires confidence in the technology.
The main suspension functions (air, springs; dampening, rebound) are housed in the “uppers”, which are the brass colored rods shown above. The inner diameter of the “lowers” house the uppers and act as a track for the suspension travel. A precise fit, good seals and lube allow the two to travel past one another with ease for many thousands of cycles. The Reba is an entry level quality fork, in contrast to the inexpensive forks found on budget bikes. For the price, the fork provides a highly tunable ride, and smooth operation. A common term when dealing with fork maintenance is stiction, which quite literally means static friction. Static friction is the force required to engage an object from rest– less force is required to overcome kinetic friction and to continue the same motion (once already in motion), ceteris paribus. Thus, clean lubed suspension stanchions allow smooth operation and respond to subtle trail inputs. Really, it is all quite simple. Below, the seals and foam rings are removed on the left . Old parts in place on the right.
New foam rings on top, and rubber wiper seals on the bottom. These parts were $22.99.
New foam wipers, soaked in SRAM Red Rum oil. A 15w oil is recommended for this fork. Heavy oils are likely to remain for longer. Lighter oil may reduce friction (and stiction). Finally, install the seals and reassemble the fork.
SRAM provides detailed technical documents for all of their forks here. Specifically, this document provides a nice pictorial overview of Reba maintenance.