Setting up the rear shock
Kevdog said:
I picked up a 99 K1200RS about 5 weeks ago and all I can say is WOW! What a machine....
My question is on preloading the rear spring. I understand the higher the number the firmer the ride but where is the reference point? Is it at the top of the "fork" or is it on the side where the adjusting screw is for the shock absorber. Where should the number line up?
Thanks for the help
Answer is...
Where the wheel is with respect to the frame when you're sitting on the bike, hands on the bars and feet on the pegs.
Rear suspension travel is 5.9 inches (comes out to some even number in millimeters) Call it 6 inches so the math is easier and there's fewer decimal points. Taken on faith (yours) the suspension should be sitting at 33% of full travel when the bike is loaded. That could be you riding solo, again but with cases and tail bag, or two up (and so forth)33% is 2 inches. So, with the bike on the center stand, and rear wheel not touching the ground, measure between the rim of the wheel and the edge of the side panel. Record that number. Then (with a trusted friend or two) get on the bike (off of the center stand) load the bike as you would for the ride, feet up (one friend holding the bike in balance) and hands on the grips. Measure (friend #2) the distance between the same two points. Get off of the bike and adjust the preload. Measure again, (wash, rinse, repeat) until the measurement is 2 inches less than what you measured the distance when the bike was up on the center stand. Preload is set. Make a note of where the preload knob is for each load.
The other setting for the shock is rebound damping (not dampening...that has to do with things getting slightly wet). It's a triangular knob on the bottom of the shock. The underlying purpose here is to get the shock back to it's normal point as quickly as possible. Too little damping and the shock comes up too fast and goes too far. Then it has to travel back down, possibly going past the "normal" rest point, and then comes back up. Takes time...
Too much damping and the shock gets to the "normal" rest point, but you could smoke a cigarette in the time it takes to get to that point. You adjust the rebound damping so that the shock gets to the "normal" rest point the quickest. This may be with a
little bit of pogo-ing (goes just past the normal point then to the normal point) because one click more damping causes just a slight bit more time to get there. Some folks will adjust so there's no pogo/bouncing, but it takes just that tiny bit more time. Truth is, either click position is probably close enough unless you're tuning the bike for Rossi. That's it...until you get Ohlins or Wilbers that also have compression damping.
