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How do I adjust my suspension? (DR350)

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Hello,

First bike, so Im learning everything as I go, and I dont have a manual. Im VERY mechanically inclined... with cars :thumbsup: and have done many motor swaps. I was delighted to see that my entire bike could be dissasembled with 4 wrenches, a screwdriver, and a pair of vicegrips... my first day it was all over the lawn. However, I just cant figure out how to adjust the suspension, and even if I could, I wouldnt know what to set it to.

First off: Mine is lowered. I bought it from someone who was 5'6" and Im guessing about 140 - 160lbs. It has lowering links on it, but I have the stock ones available to put back on. Seeing as I can sit on the bike with my knees bent and flatfooted - and the fact that Im 6'1" 190lbs - Id like to know how to do this. It looks as simple as taking off the links where they are and putting on the new ones. Anything to it other than removing four bolts?

Second: Suspension stiffness. I found the shock reservoir. Is it an oil or gas or air shock? Id like to stiffen it up considerably as putting my weight on it compresses it more than I would like, or would consider normal, even for my limited experience.

Further with this, specificaly making an adjustment. I notice that there is a... pilot screw, of some sort, in the middle of the shock adjuster. This can turn left or right about 2.5 - 3 turns. Its slotted for a flathead screwdriver and has a dot on it which looks like its meant to line up with the adjuster beneath. the adjuster beneath looks like something needs to be loosened on it and thne it adjusted with a wrench, but putting some force on it has no effect and Im not sure if what Im doing is right. This 'adjuster' has a raised circular section with flat sides, and the recessed circular partion has a dot on either side used for lining up its adjustment. Any help is appreciated:)

Third: Adjusting the spring. I can see that there is a collar and threaded spring perch, and some sort of adjuster on top of the shock where the spring sits. Is it as simple as turning and locking it one way or another? What will this ultimately result in?

Fourth: Setting the suspension. Once I know HOW to play with the suspension, what should I be aiming for as a good base? Ive read a bit about sag, but Im unclear what it is or what mine is, or how to get where I need to be by adjusting the items above!

I apologize for the long post, but there is no FAQ in here and if nothing else, this will grab a lot of search hits in the future from other confused people like myself:) Thanks for your detailed/brief/any replies!

-Sean

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I am FAR from an expension expert but.......here is what I DO KNOW. The rear shock is oil filled with a netrogen tank to control the compression of the shock. (The stiffness of it.) That setting is a personal choice. The newer 350's (like 1998, 1999) have a "clicker" or adjuster screw on the bottom of the shock. That adjusts the rebound, again personal choice.

On the shock adjusting nuts (thos 2 large nuts on top) yes, it is as easy as loosing the top (locking) nut then moving the bottom as needed then tighttening the top. You do this to set your "sag". I have done this....but I am not 100% I am telling you in the correct order. FIRST you set your static sag. That is the bike off the ground you measure from the center of the axel to a set spot on the frame. Then with the bike on the ground and you ON the bike in FULL giding gear, KICKSTAND UP, you do the same measurement (you will need 2 people to hold the bike up while you are on it). This second measurement is your race sag. PLEASE NOTE: I may be backward on those terms!!!! The difference between the two measurements is a set range......I forget what that reange is. But....this range will also tell you if the spring is stiff enough or needs to be stiffer for YOUR weight. Do a search on "race sag" "static sag" here and on the internet n general.

Regarding "lower the suspension" I have Kouba Links on mine (I am 6'-1" & 220 lbs) supposedly these are for lowering the bike......but they do more than that. I am not exactly sure what , why or how. But....I put them on after talking with MANY on the various talk boards and I am glad I did. I TOTALLY redid my suspension a month ago or so. Check out...1) http://www.kientech.com/

2) http://www.maximum-suzuki.com/forums/

3) http://www.tootechracing.com/suspension_tips.htm

4) http://www.mb1suspension.com/id8.html

5) http://www.shocktherapyracing.com/sagsettings.htm

Also call or email "Jessie" at Kientech and or Norm at http://www.koubalink.com/

This is where I got all me help.

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Pretty darn close on all counts there John.

Pitscar, I suggest you read around. There's some very nice articles on the net for setting suspension.

Just a couple of corrections for you before you get into the heavy reading. The springs control how far your suspension compresses. The shocks only control how much time it takes to reach the final point and how fast the suspension recovers. Nothign you do to the damping of the forks or shocks will change how deep they compress. Only the spring RATE and preload controls that. That screw adjuster is your damping rate adjuster. The one on the remote reservoir is the compression damping adjustment and the one on the lower end of the shock body is the rebound adjuster.

As mentioned your rear shock is oil damped and nitrogen charged. Shocks change volume as they work due to the piston rod going in and out of the body. To allow for that volume change there needs to be a compressable air or gas volume. But air or gas can mix with the oil and cause frothing and cavitation that ruins the damping. So they put in a floating piston with a seal to separate the gas area from the oil In use this piston floats back and forth in the remote reservoir a little bit as the shock rod moves in and out.

The forks work the same way but they do not bother with a floating piston to separate the air from the oil. But they have a larger volume of oil so they don't need to worry about cavitation as much and the smaller and far more highly loaded rear shock.

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Thanks guys. Ive been reading around quite a bit actually, and both of your replies serve to compound things Ive read. However, much of it out there is simply, 'set the sag to xxx'. Well what the hell am I adjusting to set the sag? :thumbsup: The term 'new' couldnt be more stressed :ride:

Im guessing the collar of the spring can adjust, but I wouldnt know how to go about doing that. Again, Im guessing tightening this downwards will increase the preload and subsequently reduce my (disturbingly large) amount of sag in the bike. I bought it off of someone quite a bit smaller than me so, given that it was setup correctly, I need to get this right, and quickly.

Bruce, I always appreciate reading what you have to say (I follow you around the internet it seems) but someday maybe I can just meet you and check out your 350 and you can walk me through some setup with it:)

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