Community Forums

GlenB · 09-30-2017, 09:24 AM

I just installed koni shocks. Great for side sway etc really nice but I seem to take harder licks dealing with seams and bridge changes... have been told go up in air pressure been told go down in air pressure. 2005 fleetwood expedition 38N diesel Michelin tires???? I usually run 95 psi in fronts...some say shocks will break in??? Help!!! Glenb

MSHappyCampers · 09-30-2017, 09:28 AM

Glen, I replaced the shocks on the Windsor with the Bilsteins three or four years ago. I didn't notice any difference in how it took the divider lines at first, but it did seem to get better with time! Hopefully the Konis will be the same!

F76Marion · 09-30-2017, 10:12 AM

Glen,

Have you ever weighed the coach and then looked up the pressure for that axle weight? I have seen this a lot, I even has a guy at tire store tell me that the tires should be kept at the maximum pressure listed on the sidewall. That is simply not true. They should be inflated for the load that they are carrying.

Frank

zekethomas · 09-30-2017, 12:23 PM

I have found that Sumo Springs help solve that problem. Our coach still launches upward at the bridge transition, but she comes down soft and comfortable.

Actually I have had to stop expecting the "big bang" when she lands, but there is none after Sumo's.

For what its worth.

Dennis_K · 09-30-2017, 12:27 PM

Which Koni shocks did you get? The adjustable red ones or the FSD gold ones?
The FSD's are designed for Motorhomes. I put a set on and didn't notice any difference in the small bumps but a big difference in controlling the the porpoising.

GlenB · 09-30-2017, 12:46 PM

Don't have the adjustable koni for my unit wish they had....tks

Coral · 09-30-2017, 09:31 PM

There is also a series call Koni EVO 99. I'm getting them next spring.

mrv8outboard · 10-01-2017, 08:05 AM

I have installed the Koni FSB's on our FRED chassis. We live on Cape Cod. Only two wats off and both use bridges. The first thing my wife noticed was no more bang at the expansion joints. I have Bridgestone tires at 100 psi front and 110 psi in the rears.

Gary RVRoamer · 10-01-2017, 08:58 AM

Shocks actually have little to do with how bumps feel to the passengers. Their purpose is to control porpoising and keep the tires in contact with the road while the suspension moves.

If you are feeling the bumps excessively, get the coach weighed (by axle or by tire) and optimize the tire pressure for the load. That will have the most direct benefit.

Steve Ownby · 10-01-2017, 09:37 AM

Quote:

Originally Posted by Gary RVRoamer

Shocks actually have little to do with how bumps feel to the passengers. Their purpose is to control porpoising and keep the tires in contact with the road while the suspension moves.

If you are feeling the bumps excessively, get the coach weighed (by axle or by tire) and optimize the tire pressure for the load. That will have the most direct benefit.

Gary is 100% right. On a heavy coach with air suspension, the shock will have very little influence on the sharp "hits" to the coach. I have a friend who took the shocks completely off his coach & take it out for a drive. In his opinion, he could feel no real change to the first hit or compression of the air bag. The shock's primary function is to dampen and stop the rebound.

Check ride height and adjust tire pressure to support the weight on that position. The tire's on an axle must be at the same pressure so adjust to the heavy end.

dezolen · 10-01-2017, 10:19 AM

Such contradictions. All these DP owners are always saying how wonderful they ride with air suspensions etc and now it sounds like they are not much better than my lowly gasser.

funjnt · 10-01-2017, 10:32 AM

We had a ride height valve going bad and front of coach was low. When I hit certain bridge seams it hit hard, so hard I thought the windshield was going to fall out on occasion. Check your ride height and see if it's low.

TLGPE · 10-01-2017, 10:54 AM

Sorry for the confusion, Dez, but the subject is shocks. The air ride system is MUCH smoother than steel springs.

The "dampers", or shock absorbers don't really control shocks, they control rebound. That means that if you hit a bump, the coach will rise up to go over it and then drop back down again, bounce up again, and down, and up, and down.............like a rubber ball. The shock absorbers add friction to the motion so that the bouncing damps down sooner. That continuing bouncing motion is called "porpoising" after the sea creatures that swim with that motion. Shocks do not make the bumps less severe, they just stop the residual motion.

The fact is, that shocks ADD to the bump, because they resist the motion of the suspension. Typically they are designed to resist the rebound motion much more than the compression motion but they do resist. The result is that spending lots of money for fancy shocks will do little to smooth out bumps, but it will make your wallet lighter.

Now, it's important to note that the overall feel of the drive can be greatly improved with the right shocks. Worn out or misapplied shocks can leave you bouncing around, wobbling along a crooked path and in general hating the drive.

I don't sell shocks, but I am considering new ones us for our coach. We currently have Bilsteins, but I don't know the age. When we get stopped for the winter, I'll look into it more.

Sorry about the Sunday morning ramblings...............

Tom