I only have one race on mine so far and a little testing around the house. They're a little firm on the smaller chop, but in the gnarly sections, they eat the terrain for lunch.

My fronts have a very firm spring rate with fairly light valving. This helps keep the front end stable in the corners, but allows them to take up the big bumps without being too harsh.

Need more time on them to really develop an informed opinion. Don't have any jumping time on them yet.

I don't think they will increase wheel travel over Works. I did some measuring and the Elka bodies are a bit longer than my old Works bodied TCS's and the shaft travel isn't quite as long - which means ride height is increased and travel is decreased by small amount. This sounds worse than it is. The ride height is not a problem, because it can be adjusted with sag & actually helps keep you from bottoming the frame on the ground. Travel is not that big a deal either because if you have too much, you'll bottom the frame on the ground before bottoming the shock. It's a fine line and there are a lot of variables. I had the actual measurements at one time, but have lost them...

Installation wasn't too bad, but they use very high quality line and fittings on the lines to the rezzy's. While this is great, it makes reservoir installation a bit tricky. The fronts weren't too bad after I found a good place for them. I am still not happy with the rear rezzy mounting, it was easy to mount, but I feel that it is too close to the exhaust silencer.

If I had it to do again, I probably would go with piggyback fronts. I just liked the looks of the rezzy shocks better.

Let me know if you have any more questions.

 

I agree Gabe, the angle at which the line comes out from the shock plus the lack of flexibility with the rez line really limits where you can place the rear reservoir. I too questioned placing it right above the exhaust silencer.

After running the machine a while, the reservoir really didn't get too hot; I could still hold the reservoir with my hand, it wasn't uncomfortably hot. I am, however, running the IDS2 - which has a much smaller diameter than the stock silencer.

Let me know of any other possible placement options you have thought of.

ogre

 

i was thinking that if you take the tool box off that might provide a place to mount but im not sure

 

"shaft with a shim stack piston"

whats that about? is that what everyone uses?

 

i think that if u are going to get a high performance suspention you should get the custume built Axis thats my oppinion good luck!!!!!!!

 

mt400ex,

I "borrowed" this from another site. It is discussing why motorcycle suspension works better with shim-type falving, but applies to quad shocks as well.
------------------------------quote--------------------------

Cartridge Forks
I am often asked the question, "Why cartridge forks? What's so great about them?" Riders know they're better but don't know why. Let's clear the air. Let's say you're bopping down the road, you charge into a corner and hit the brakes, the font dives radically and the bike feels like a wallowing pig. The later on you hit a square-edge bump and it feels like your wrists are going to break. Wait a minute, First the bike was too soft, then too harsh, What gives?

Well, perhaps the problem is your basic fork design. Internally, there are two types of forks, damping-rod and cartridge. If you have an old-style damping-rod fork, you're fighting and uphill battle (there are excellent solutions for that design but we won't get into that now).

A damping-rod fork is fairly simple: all that happens is oil is shoved through fixed orifices. This type of damping is call "velocity-squared" damping. The faster the wheel moves vertically, the more oil is shoved through the holes.

This is an important point. The speed of the bike is not nearly as critical as the shape of the bump. If you have 2-inch high bumps that's square-edged, the wheel has to move vertically very quickly, even at low speeds. On the other hand, if the 2-inch bump has a ramp that's 2 feet long, you can imagine that the vertical wheel velocity is much less. Now, of course, the bike speed does matter: if you double the bike speed over particular bump, you will double the vertical wheel velocity.

If the vertical velocity is doubled, the oil-flow rate through the damping holes is doubled. The interesting thing about fluid flow through fixed orifices is that the damping resistance is not doubled but instead increase with the square of the velocity; in other words, it increase by four times.

This situation is sometimes referred to as hydraulic lock. At some point the damping force increases so rapidly that the eintire bike defelects instad of the suspension absorbing the bump.

The problem is that "fixed orifice" damping-rod forks are too progressive. Fixed-orifice forks have very little "low-speed" damping and a lot of "high-speed" damping (vertical wheel speed). With very little low-speed camping, the fork dives excessively, and with a lot of high-speed damping you'll get a harsh spike: the worst of both worlds.

Another limitation is revealed during revalving. Typically, revalving a damper-rod fork involves enlarging or reducing the holes, or installing thinner- or thicker-viscosity suspension fluids (there are other solutions). This decreases or increase the damping through the entire speed ranges, to the bike is better handling the spike but will be better at handling the spike but will be even worse under hard braking, or vice versa. These changes will get you in the ballpark but almost always have compromises.

One solution is a cartridge fork. Mechanically, most cartridge forks use bending-shim-type construction instead of fixed orifices. This means there's a damping piston with a series of shims (they look like thin washers). The shims are stacked up against the face of the piston. When the oil flows through the piston, it forces the shims to deflect away from the piston face.

This creates damping at very low velocities. At very high wheel velocities, the shims deflect more and don't create as much high speed damping as fixed-orifice-type designs, meaning that the spike on square-edge bumps is reduced. With a cartridge fork, the damping is less progressive than with damping rods.

An added advantage of a cartridge fork is that the damping curve can be modified, or revalved, in a much more precise manner. For example, if you need less high-speed compression damping but the low-speed is perfect, the high-speed can be modified without affecting the low-speed compression because each circuit is affected by different shims when properly set up. "
-------------------------END QUOTE------------------------

Okay, so they aren't called cartridge forks, but the valving found in Elka, TCS and Axis work on the same principle. It's easy to understand, as the article points out that the shim-style design when set up properly will perform beyond the capabilities of a standard ball and check valve type design. Hope this helped some.

 

Thanks alot bash! That cleared it up very well. [img]i/expressions/face-icon-small-smile.gif[/img] I still have a few years until I'm going to get some after market suspension since I am only 15, but now I can help out others and am prepared for when I go shopping.

 

Sorry meant to reply before, got sidetracked and forgot.

The article Bash posted somewhat applies, they're talking about the fixed orifice of a damper rod fork which is different than a check ball and spring setup in a Works or Pep shock.

Shim stack pistons inside the shock are very simple but effective devices. They are basically the only valving used in modern, high travel suspensions like those found an practically all motocross and trail style dirtbikes.

The stock 400EX rear shock is a shim stack shock.

Works uses a check ball and spring setup. Can't comment too much on those because I haven't personally tried to valve a set. I have, however valved my own shim stack shocks before and it's really cool what can be done with them.

If you want to see what the piston and shims look like, go to Custom Axis' website and download their manual. It has some explanations and diagrams - good reading.