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Join Date: May 2012
Location: Buckinghamshire, England
Posts: 9
Suspension Question

I apologise in advance for a silly question.

When we talk about measuring the front spring length 'unloaded', does that mean with all the sag lifted out by pulling up on the bars? Or is unloaded just with no additional weight e.g. rider & full fuel tank?

If I lift the front by the bars and let the weight back down gently, I get about 183mm spring length. If I push down and let it back up gently, the spring length is about 170mm.

So about 15mm difference at rest depending on if the suspension is settled after loading or unloading it.

There are no threads showing at the top so I can't get any more spring length as a start point.

I have read several threads on suspension setup, but I am still not clear on the starting point with regard to spring length (as you can tell). I'm experienced at general spannering but a bit of a novice with suspension setup. This bike (12S) feels almost great and I'd like to get rid of the 'almost'.
Old 06-02-2012, 09:44 AM
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Join Date: Feb 2004
Location: Western NY
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Here, quicker than my typing it.

Race Tech - Setting Sag
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Old 06-02-2012, 11:38 AM
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Usually, "unloaded" means wheel off ground, suspension fully extended.
Old 06-02-2012, 02:16 PM
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Thanks LeafMan, that's what I needed to know. In that case I think I am starting from the right point.

PFFOG, that looks like a really good, useful article. I will take time to study it.

I went out for a short run this evening, got a couple of miles and decided to increase the front damping. I had been thinking there was too much damping but it hadn't helped going less. I increased by two clicks from my start point (first time I went that way). I checked it by pressing down on the bars and letting go. It has really stiffened it up - only two clicks - I thought this is wrong, it'll be much worse (the harshness).

But riding it, I thought wow!this is what I have been looking for. I could not believe two clicks could make that much difference, and to me, it was counter-intuitive.

I hope for good weather in the next couple of days to try it out on different roads to see how she is.

Thanks for the advice, I'll spend more time on this till i uncover the bike I know I have.
Old 06-02-2012, 02:41 PM
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Checking dampening by pushing down on the bars is difficult. Best thing is to do what you eventually did. Take it for a ride over some rough surfaces etc.

Suspension set-up is an art of striking a compromise. The goal is to find an optimal setting that will work for most situations that you encounter.

As road conditions change, so does your need for different settings. Unless you want to stop and continually re-adjust your shocks, you must find the compromise setting that works best for most situations.

After that, you may still have to stop and crank up the pre-load for added weight or change dampening for unusual conditions etc etc etc.
Old 06-02-2012, 06:40 PM
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i have adjustable compression and rebound on both shocks, plus the FCK (fat chick knob) to adjust preload in the rear.

i have three basic settings:
freeway: the bike is smoothed out, doing it's best impression of a gold wing. nothing happens quickly, and overall the suspension is basically mush. A 2 on the scale, or a 4 if you're bashing you way through LA county.

sweepers: the kind of roads jeff williams and shreddr like: fourth and fifth gear snakey roads. some triple digit corners. the bike is tighter all around, but not harsh. A 6, maybe 7 on the scale. it's firm, but doesn't snap back to attention after battling a bump.

tight stuff: second, third gear twisty roads. this setting is closer to what i'd run on a track, but softened up a little to suck up the road bumps. An 8, rarely 9 on the scale (10 hurts wrist, balls, shoulders, knees too much, not worth it). the bike is stiffer on compression and hard to bottom out. rebound is faster. overall, not a pleasant ride, but you're there to straighten out the corners, not lazy-boy/nap your way down I-40.

all three setting are written down, so it's really easy to spin a clicker. takes about 2 minutes to change a setting, most of which is spent fumbling through the tank bag, digging for my cheat sheet to get the numbers.

if i'm going commando (no map, gps or current road knowledge), i leave it on the sweeper setting and work around it.

the best part is, just like with women, the more you play with the buttons and knobs, the more response you're going to get.
Old 06-03-2012, 04:47 AM
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Old 06-03-2012, 04:47 AM
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