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: Rev Mxzx 440


Udamon77
09-14-2003, 04:20 PM
hey guys.......it's been a while since i've been on here, but the summer is coming to a close and that means i'm not working 65 hours a week. it's good to be back....

well, i was just wondering how i need to tweak the suspension on my sled. i've heard a lot about it, but don't really know any specifics. i have a REV MXZx 440, and i was wondering how to set it up for 1) trail 2) lake 3) screwin' around doing wheelies and stuff

i know this is a broad question, and it's not like there is a "set" answer, but anything that helps me understand my suspension more will be greatly appreciated. thnx for your time.

z24bbx
10-01-2003, 12:09 PM
if it's new start with the factory settings adjusted to your weight for trail riding,for dinking around un-couple the chassis ,loosen limiter straps this will help get those skis in the air,but it won't take the bumps very good,have fun :p

Udamon77
10-01-2003, 05:28 PM
thank you very much..........i knew someone would step up sooner or later. thanks for your time.

Dynamo^Joe
10-01-2003, 06:42 PM
I agree with factory setting somewhat, but disagree about not taking bumps very good.
With bone stock settings the sled is somewhat stiff in the center shock for up to 200lb+ driver.

Stiff center shock:
With the center shock being stiff and the limiter strap sucked in, you get "A$s swapping” this is when you go thru slight bumps at 40 mph or more and the sled's rear end wants to swap a bit back and forth.

Limiter strap position:
With the limiter strap sucked up this is great for low speed deep slushy snow on a racetrack, but compound this detail with a stiff center shock for fast trail riding you get "darting"

When on flat and little if no bumps, the sled thinks its 8 feet long because the skid frame is not really performing any action. When you get into bumps the sled thinks it's only 4 feet long.
With the center shock tied up from the limiter strap the shock spring is compressed in a tighter position. The Factory Low speed shock valving set to "stiff", the concert of these two will provide a very stiff resistance to the oncoming bumps. The center shock is stiffer and slower reacting than the rear/rear shock and torsion spring. So what you get when the sled going over the bump is High ski pressure at the beginning and high center shock force against the bump as the skid frame passes over the bump.

Now with the skis having a lot of ground pressure, you will get darting and eventually get arm pump.

With these suspension details it will act good in deep powdery grainy snow, but on hardpack fast trail, you are asking for a$s swap that you may not get out of if the pitch of the top of the bumps are just right for the speed you are going.
I know all about a$s swap and have scars to prove it from my sled running me over twice. he he...
The sled will swap and the displacement from left to right increases each time. Most times you can get out of it by grabbing the brake with full squeeze and pinning the throttle full squeeze. For some reason and I don't know why, it straightens the sled out.

I have done this with several REV chassis 440's.
Let the limiter strap right out. This will let the full skid frame be on the ground. This will let the compression spring have less compressed force and have more travel to suck up a bump with smoother rebound.
I get guys from 150 to over 200 lbs to have the Low Speed Screw on 2 turns out. This will help provide a plush ride and let the sled think its 8 feet long.
Turn the High Speed valve nut to 1 or 1-1/4 turn to make the action stiffer. When you get into some big-a$s bumps where other sleds will bottom out, your sled will not bottom out because of the action of this valve circuit.

For the trails you drive on 90%, you can probably leave the rear/rear shock settings on factory, as they seem to be good. But if you pound in more extreme bumps, then turn the Red nut "high speed valve circuit"...turn that nut in to stiffen up the action so you won't bottom out.

With the limiter strap out, yes you will have less steering affect with the skis, but not to worry...it’s a rev chassis. LEAN into the corner and use some body english.
...You will still leave other sleds in the sno dust.

Udamon77
10-02-2003, 04:35 PM
wow, thanks for the very detailed and accurate answer......your time is greatly appreciated. one thing though, i was wondering what your definition of "a$$ swapping" is. i just want to remove all guesswork so i can know what to expect with my mods.

any other feedback you guys can give me is still welcome

Dynamo^Joe
10-03-2003, 07:40 AM
[i]if you were to watch an overhead view looking straight down at the sled moving forward....[i]

The sled goes over a bump, the rear end hops off the ground and swings back and forth in a pendulum motion...The exagerated move would look like the rear bumper is started swinging from a 6 oclock position to an 8 oclock position swinging back to a 4 oclock position....

it gets worse and worse till finally you flip the sled on its side, then you rudder and roll it...
and in my case, pitch end for end tip to tail.

*ugh* :nervous:

Udamon77
10-03-2003, 02:16 PM
ok, thank you very much for the description. hehe, i don't think i really care to let my sled take me for a ride like that very soon. !!! :0: i doo like to push the limits though...... :devil:

Udamon77
10-10-2003, 01:17 AM
hey, i was just wondering........is this the best overall suspension setup that you recommend? or is it just for certain conditions? thanks.....

I have done this with several REV chassis 440's.
Let the limiter strap right out. This will let the full skid frame be on the ground. This will let the compression spring have less compressed force and have more travel to suck up a bump with smoother rebound.
I get guys from 150 to over 200 lbs to have the Low Speed Screw on 2 turns out. This will help provide a plush ride and let the sled think its 8 feet long.
Turn the High Speed valve nut to 1 or 1-1/4 turn to make the action stiffer. When you get into some big-a$s bumps where other sleds will bottom out, your sled will not bottom out because of the action of this valve circuit.

For the trails you drive on 90%, you can probably leave the rear/rear shock settings on factory, as they seem to be good. But if you pound in more extreme bumps, then turn the Red nut "high speed valve circuit"...turn that nut in to stiffen up the action so you won't bottom out.

With the limiter strap out, yes you will have less steering affect with the skis, but not to worry...it’s a rev chassis. LEAN into the corner and use some body english.
...You will still leave other sleds in the sno dust.

Dynamo^Joe
10-10-2003, 01:35 AM
My friends and I come up with those settings for the trails we ride on regarding valve setting and limiter strap.
The trails we ride on are very extreme bump conditions. Pretty well every ride in the several places we go, I am nearly soaking wet in sweat from working the sled good n hard. I will replace my bump stops a few times per season because I cycle the suspension fully all the time. which is why i like full-out limiter strap

The only valve setting that may be too stiff for you is the High speed valve [red nut] for the way you ride.
There are owners across the net who have given me feedback that this seemed pretty good, especially when they were going thru very rough/fast terrain.

I would pick a trail where you find you do not particularly like the ride of your sled, then try changing the settings.
The tools in your sled kit are enough to adjust the shock valving.
Just remember your present settings "write them down" and go play.
Remember, never turn any of the brass screws in to less than one turn or damage may result to the valve needle inside the adjust casing. Always turn the screw in until it bottoms and then one full turn out. From there you can count the "ticks or clicks" that each screw makes.
If you dont like any of it, set them back to your original tune settings.
It's up to you....It's your ride.