Saturday, June 20, 2009

WR lowering post o' the day: how to set sag

Sag. No, not the Screen Actors Guild or what happens to pretty body parts when you get older. Sag as in suspension sag settings.

You'd be surprised how many riders on all types and brands of bikes do not know how to adjust sag or why they need to.

How to adjust sag easy tutorial:

The above link mentions 4" sag which is common for linkage bikes with 12" travel. You want about 1/3 sag for total travel. Obviously the WR R/X does not have 12 inches of travel.

While I'm here, how about a quick sag tutorial as a refresher?

Many times people say "put more sag in" to get your feet closer to the ground but what happens is you are using too much travel and now you are riding too far into the progression of the shock spring. This makes the bike ride very rude AND you have less travel remaining to handle the big hits. And often times when too much sag is put in the front end understeers because the geometry cannot compensate. It will ride like a chopper. With proper sag you can adjust the front forks to get a balanced ride. And NO there is no need to raise the forks the same amount as the rear was lowered because changes to rake/trail (the forks being slid UP in the triple clamps) affects geometry at a different rate than changes to the rear.

Ten millimeters is a very popular starting point for the WR R/X forks when the rear has a lowering link. Three to six mm for others bikes is the norm. You then adjust the forks up or down based on personal preference (some ride tiiiight woods and some ride high speed sand washes and some are kinda in the middle).

When you don't have enough sag your rear wheel cannot follow the terrain efficiently and you lose traction, get a higher center of gravity and the suspension wants to bounce and skitter across the terrain which just magnifies the lack of travel. Eventually your bike is traveling slower and working harder over the same terrain that a bike with proper sag is absorbing and working WITH to propel you forward.