Setting up the suspension, 1300?

Joined
Aug 21, 2008
Messages
128
Age
81
Location
Ellensburg, Wa
I'm new to ST1300's and the board. I've heard that setting up the suspension correctly is the key to "the weave," which I have never experienced, nor wish to....... how's the suspension set up, then?
 

Marshal_Mercer

Bumbleberry + Crumble = Yum!
Joined
Dec 8, 2004
Messages
601
Location
Alameda, CA
Bike
Has new home
STOC #
6214
I'm new to ST1300's and the board. I've heard that setting up the suspension correctly is the key to "the weave," which I have never experienced, nor wish to....... how's the suspension set up, then?
Welcome aboard.

Go here and you should be pretty well set until you want to really dive in.

Marshal
 

Raven

"two wrecks" - RIP ACL
Joined
Aug 5, 2006
Messages
925
Location
recalculating
Bike
Aprilia Caponord
STOC #
6406
The calsci sight is fabulous but the rebound damping they recommend is too hard (it slows down the rebound too much) and can have negative effects on your traction.

Setting Your Sag:
For a base-line set-up you can do the following and then fine-tune from there. (You'll need some friends to help you measure since you'll be on the bike.)

- Put the bike on the center stand to get the rear wheel off the ground and extend the suspension.

- Use a measuring tape to measure from the center axle up vertically to a point on the chassis. Measure in millimeters to make doing the math easier. Record this measurement and lable it M1.

- Take the bike off the stand and have a couple of folks help hold the bike up while you get on it in riding position. Have a third friend push the rear down about an inch and let the rear come back up slowly (don't bounce it). When the suspension stops, measure from the center axle to the chasis point you measured to before. Record this measurement and lable it M2.

- With you still in the riding position get your third friend to lift up on the rear of the bike about an inch and let it settle slowly (still no bouncing). The measure again from the center axle to the chasis point. Record this measurement and lable it M3.

Do the following math:
M1 - [(M2+M3)/2]

This gives you your static spring sag. Ideally your sag should be set somewhere around 28-33% of total travel for street riding (front and rear) which translates to somewhere between 30-35 millimeters. Too much sag means you need more preload while too little sag means you need less preload. If you run out all your adjustment and still have too much sag you'll need stiffer springs. If you run out all your adjustment and have too little sag you'll need shorter or lighter springs.

You do the same thing to measure your front sag and you'll want 30-35 millimeters of sag there as well. Since the ST doesn't have front suspension adjustments you may find you need to adjust the thickness of the oil, add spacers, cut the springs (not likely), or get different springs in order to get a good sag set-up.

Doing the above will give you a base-line suspension set-up for front and rear. You can then adjust that further based on your riding style and preferences. If you're planning a track day, you might want to stiffen things up and run it in the 23-27% range (25-30mm) because you're not worried about road bumps or uneven pavement. For daily riding you might decide you want things to run a bit softer and run your sag closer to 33% (35mm). Then for twisties you might decide to run in the 27-28% range.

For greater detail on setting up suspension, Lee Parks' Total Control has an entire chapter on suspension and uses the above formula to get your base-line set-up.

Setting Your Rebound Damping
It's important to remember that the REBOUND DAMPING is NOT weight sensitive. I've adjusted over 25 ST's over the past two years teaching the Total Control Advanced Riding Clinic and, without fail, proper rebound damping has been at ~1 & 3/4 full turns to 2 full turns out from full hard on a stock shock. Any harder than that and the rebound is too slow (bounce on the rear with it set at full hard and you'll see how slow the bike rebounds - looks almost like it's sticking).

So to set your damping, set it to full hard and bounce it. You'll need a friend to help stabilize the front and hold the front brake while you stand at the back and give the suspension a good push down. When you release it just let it rise on it's own. Set at full hard it will look like the suspension is sticking as it rises up. Now set it to full soft and bounce it again. It will pogo so fast that it actually pulls the wheel off the ground and oscillates. Now, turn it back to full hard and dial it out 2 full turns. Bounce it and it will come up and settle without oscillating. If it oscillates, turn it a 1/4 turn towards hard and bounce it again. This will be darn close to "just right." Play around in 1/4 turns to get it dialed in perfectly - it should come up and just settle without looking like it's sticking and without oscillating.

Once again, we only have adjustments for the rear suspension. You can do the same measurements for sag on the front and check the damping on the front but you can't change it unless you up-grade the suspension.
 
Joined
Apr 22, 2008
Messages
86
Location
Wildomar Ca
Setting up your suspension probably helps but its not going to stop the swing arm from "yawing" (high speed weave) at the pivot points once you hit the magic loading point (problem as admitted by Honda).

I have my spring preload usually set on the hard side with the damping set so once it recovers from a bounce it settles without "floating". I have only had my bike over 100mph once so far so I am not to worried about the high speed weave issue. I doubt I will ever bust 120 mph, especially with my wife on the back.
 

Marshal_Mercer

Bumbleberry + Crumble = Yum!
Joined
Dec 8, 2004
Messages
601
Location
Alameda, CA
Bike
Has new home
STOC #
6214
Raven:

Right you are. I was taking the "small steps" approach.

Since you brought it up, I am sure that you are aware that the stock ST1300's damper is metering rod position dependant. That means that the resting dynamic sag length modifies the damping characteristics. This equates to: more preload on the spring yields less damper effect. If one likes to ride at the lower end of the sag spectrum (small sag), the damper screw will need to be farther in, in order to better follow the bumps in the road. A larger sag will require the damper screw to be farther out to accomplish the same effect.

Marshal
 
Last edited:
Joined
Sep 1, 2008
Messages
13
Location
PA
Raven:

Right you are. I was taking the "small steps" approach.

Since you brought it up, I am sure that you are aware that the stock ST1300's damper is metering rod position dependant. That means that the resting dynamic sag length modifies the damping characteristics. This equates to: more preload on the spring yields less damper effect. If one likes to ride at the lower end of the sag spectrum (small sag), the damper screw will need to be farther in, in order to better follow the bumps in the road. A larger sag will require the damper screw to be farther out to accomplish the same effect.

Marshal

OK,

So what you are saying, the more preload you have, the more you might have to increase the damping to be equal to the same dampening effect?

So weight would have an indirect effect on the dampening as you adjust the preload for that weight?

fitz
 

Marshal_Mercer

Bumbleberry + Crumble = Yum!
Joined
Dec 8, 2004
Messages
601
Location
Alameda, CA
Bike
Has new home
STOC #
6214
OK,

So what you are saying, the more preload you have, the more you might have to increase the damping to be equal to the same dampening effect?

So weight would have an indirect effect on the dampening as you adjust the preload for that weight?

fitz
Yup and yup. Kind of counter-intuitive, huh?

Marshal
 
Last edited:
Top Bottom