Help Setting up Suspension...

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Dec 3, 2000
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#1
I plan on racing some NETRA hair scrambles and wanted to get my suspension properly setup before my first race (the back shock is gone and the front forks are t00 but thats another story). I was wondering if you guys could help me figure out the correct spring rates, sag, compression, and rebounding setttings i should be running. (so i can set everything up once i get everything fixed up). Here is my info.

My Bike: 1992 KDX200 w/ Stock Suspension

My height/weight: 5' 8", about 215 w/ all gear.

Skill Level: Novice (I like to ride really agreesive tho)

Terrian I Ride: Tight Twisty Northeastern woods w/ lots of rocks and ruts and roots w/ the occasional trip to the sand beds and an MX track.


Any help would be appreciated.
 

Jeremy Wilkey

Owner, MX-Tech
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Jan 28, 2000
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#2
ATOM...

I'd go .44's with an RT emulator and a 5.0 in the rear. Set your compression and rebound around stock and go from there. Here is my offroad tunning guide to help dial it in.
Regards,
Jer

Getting started, shock:



Setting the rebound:

1.) Find a relatively fast trail with braking bumps, rocks and roots leading into the entrance of a corner. Reduce (Turn clicker out) the rebound damping until the rear end begins to hop or feel loose. Finally, increase (Turn clicker in) the rebound damping until the sensation goes away.

2.) Find a log or ledge that tends to bounce the motorcycle after hitting it. If the rear end bounces up uncontrollably, add rebound. (Turn clicker in)

3.) Find some large whoops. The motorcycle should track straight through the whoops with the rear wheel extending to the ground before the next impact. If it does not perform as described, as above, it is packing and the rebound dampening should be reduced! (Turn clicker out) (Please note the guide for sand set-up, as these rules don't apply for sand.)

4.) Find a corner with acceleration bumps, rocks, and roots on the exit. The rear of the motorcycle should follow the ground. If the rear end "breaks up", reduce the rebound. (Turn clicker out) (If this fails soften the compression two clicks.) (Turn clicker out)

Setting the compression:

1.) Find some rough sections, a large jump and a couple of "G-Outs". The shock should bottom on the roughest section but it should not be a slamming sensation. Add compression to fight bottoming. (Turn clicker in.) But avoid going to far as the suspension's ability to react to small variations of surface and rocks will be sacrificed in the trade. Remember the adjusters have a primary effect on the low speed, so even a large change in setting may only effect bottoming resistance slightly. Remember bottoming your suspension is not necessarily a bad thing. You should strive to bottom off the biggest bottoming load obstacle on the trail. If you don't you're not getting maximum plushness from your suspension. Run your suspension as soft as you can get away with but remember that if the trail has sand sections or lots of g-loads this will work against you.

Getting started, forks:

Setting the compression:

1.)The forks should react to all trail variations. If the forks seem harsh on small bumps, holes, rocks, or roots soften the compression. (Turn clicker out) If they are relatively smooth, stiffen (Turn clicker in.) until they do feel harsh and then turn back a click or two.

2.) Now find the rough part of the trail again. The forks should bottom over the worst g-load or jump. If harsh bottoming occurs, add oil in 5-mm increments.

Setting the rebound:

The rebound damping is responsible for the stability and the cornering characteristics of the motorcycle.

1) Find a short sweeper. When the forks compress for the turn, the speed at which the forks return is the energy that pushes your front wheel into the ground. If the forks rebound too quickly, the energy will be used up and the bike will drift wide, or wash. If the rebound is too slow, the bike will tuck under and turn too soon to the inside.

2). With the bike turning well, the wheel should return to the ground quickly and not deflect off successive impacts. If it does, reduce the rebound. (Turn out)

Guidelines for different conditions:

For hardpack to intermediate:

Set the compression softer, (Turn clicker out) front and rear to help get maximum wheel contact and plushness.

Sand conditions:

(Non-square edged bumps); More low speed compression and rebound are necessary. Start by adding 1-2 clicks (Turn clicker in.) of rebound and as the track gets rough, add compression 1-4 clicks. (Turn clicker in.) (Supplementary sand set-up techniques). Harshness is a result of packing in forks. Remember to add compression (Turn clicker in) to help keep the front end from packing The rear suspension will exhibit packing by swapping. To eliminate swapping begin adding compression (Turn clicker in) until the bike tracks straight and then add rebound (Turn clicker in) to keep the rear following the terrain of each whoop. Don't be concerned if your clickers are nearly maxed out in sand conditions. Unless of course you had your bike revalved for sand.

Rocks and Roots:

Rocks and roots will make your suspension work at it’s worst. Try reducing compression till the suspension can react and not deflect off every impact.

Unpleasantries?

Head shake:

Adjust the forks lower in the triple clamps. If that does not improve the suspension then reduce the rebound on the front fork. (Turn out)

Excessive rear end kick:

Check for packing, which is identified by kick to side in hard to loam conditions. If you observe packing, soften rebound. (Turn clicker out.) This can not be avoided if you brake improperly and lock the rear wheel up and/or pull in the clutch, on the entrance to corners.

Keep a record of the conditions and the different settings if you ride in different areas. That way you can start at a point that worked well the previous times.

General Ideas:

Offroad suspension is designed so you have a decent amount of low-speed compression so you will have decent stability and control of your motorcycle, with a absolute minimum of highspeed compression for a plush reaction to sharp spikes of shaft movement. Remember that if you make the suspension too soft you will use lots of energy just maintaining direction, and control. Be careful when you set it, there is a difference between soft and plush. Soft is often hard to control and harsh, while plush is smooth and controlled. The goal is to maximize control and comfort. Think about the entire section of trail or the average conditions of the trail. Factor in your skills as a rider and then select the setting that will provide the best overall ride characteristics. Consider that in offroad riding you will encounter an incredibly wide range of conditions and you’ll need to shoot for the middle ground or your suspension will be very good in some sections and very poor in others.