Is rod force a bad thing?

In many cases, rod force itself really makes no difference.  BUT, in situations with low grip surfaces, many drivers do not like the "feel" that the rod force causes.  In these cases, many drivers are willing to put up with the disadvantages of twin-tube shocks for the forgiving feel they provide.  The real problem with rod force in a conventional mono-tube shock is that it varies as the shock moves through it's stroke and as the temperature changes. ZRF technology eliminates this variable, because if there is no rod force, there is no variable.

A thru rod shock is stiffer than a non thru shock because?

The thru rod shock adds stiffness which takes load off the piston band.  This added stiffness decreases seal drag. Especially when mounted at an angle which side-loads the shock.

Are there other advantages?

Yes! There is:

  • no rod force change with displacement
  • no rod force change with temperature
  • less cavitation because you can run more gas pressure without increasing rod force
  • twin-tube feel with mono-tube advantages
  • lower seal drag
  • on coil-over shocks, drag reduction can be huge
  • no need to replace your existing shock inventory to gain thru-rod technology and advantages

So, if you like the feel of traditional twin-tube shocks, this is for you.  ZRF shocks will give you the same feel as a twin-tube shock but with the consistency and user re-buildability of a mono-tube.

Contact Tri-Nel Solutions to see if a kit exists for your shock brand!


Tri-Nel's new ZRF Shock Kit can give you zero rod force  thru shocks

without having to replace your entire shock inventory. 

Continue to use your existing shocks with our thru rod upgrade kit for true ZRF advantages.

What is ZRF technology?

The zero rod force shock eliminates rod force caused by gas pressure pushing on the rod end inside the shock. By using a thru rod design, rod force is eliminated.

What is rod force?

In a mono-tube shock, cavitation is prevented by running nitrogen to raise the pressure. This is much like using a pressurized cap on your radiator.  The gas pressure pushes on the end of the shock shaft that is in the pressurized oil. The other end of the shock shaft is being pushed on by normal atmospheric pressure (14.7psi). The amount of pressure in the oil multiplied by the area of the shock shaft creates the rod force.

The Next Hot Ticket is Thru-Rod technology

If you have a need . . . . .Tri-Nel has the solution!