I'm wanting to replace the OEM shocks and thought I would ask if any members have tried the Bilstien Comfort shocks. I know many members prefer the Koni FSD and both would probably be noticeably better than the OEM Bilstiens. The Koni's are considerably more $$.$$ and may be worth the cost. Motorhome magazine had an article that gave the nod to the Bilstien for a softer ride over rough roads and expansion joints, like I40 thru Oklahoma. Any personal experience with both? Pro's and con's on either?
They are both great shocks, had the Bilistiens on my SOBs, Konis on this coach. Got to say, these KONIs provide the BEST ride I've ever had! ^.^d
I checked the Motorhome magazine article and noticed that it was 9 years old. I would be interested in finding something current. I don't think you would find comparisons on a blog, since most of us buy one or the other. I would pay attention if someone had a negative experience - harsh ride over expansion joints, for example.
I am also looking for shocks, but are leaning toward the Bilsteins since they are significantly less and offer an comparable ride to the Konis. In the nine years since the article, I would assume that they have only improved.
I would go with the Koni's.
I took the Foretravel production tour today and they put Bilistiens on the Realm. I did not ask about the IH-45.
The tour is impressive.
Jim
2002 U320 42' with 1000 watts of solar
According to Foretravel's 2019 IH-45 Product Guide they use Bilstein shocks too 60mm front and 46mm rear and tag.
I have never had Bilstein shocks so I cannot compare but I have put Koni FSDs on my previous Class C Leisure Travel Van Libero and it made the ride and handling remarkably better. I wished I had put them on sooner!
Seems like our estimable moderator, Mr. Wolfe, did some modifications to beef up the front end on ours for the KONI shocks, maybe he remembers?
Mike,
You have the ONLY U225/U240 with Koni FSD shocks. Our coach was the design coach for the FSD shocks on RV's. I worked with the engineers at Koni in Hebron KY on them-- that is another story!
Yes, Koni has FSD's for newer Foretravels, but they know there are not sufficient number of U225/U240's to warrant a separate product run.
I am considering just replacing the four fronts now and then changing the rear four later this year or next. I would like to do the fronts before our trip to Utah and Colorado this summer.
Do they all need to be changed at the same time?
Is it not a good practice to use different shocks on the front than the rear?
Biggest reason for this is just to save a little time and $$.$$. The coach doesn't ride bad now, probably is softer and quieter than most new coaches that cost less than 500K sold today. (says a lot for the FT unihome/unicoach with no slides)
Not sure how much the shocks can dampen the expansion joints and potholes anyway, tire pressure would probably affect the ride more than shocks. Pressures are set according to the Michelin tire chart and our front and rear weights.
I am leaning toward the Konis even though they are the more expensive, won't need to purchase shocks again for a very long time.
Just wondering why FT uses the Bilstiens on new coaches.......... :-\
No problem with different shocks front to rear. Probably would NOT use different shocks in front of/behind a particular axle.
Yes, the Koni FSD's do make expansion joints "less rough", as their dual valving gives them very little dampening over those small, sharp bumps. Agree, tire pressure is at least as important, and probably more so.
Are you saying I cannot get replacement Koni shocks? Yikes!
You MAY be able to get them reworked by Koni, but NO, there are no new ones.
They should still have the valving information under my name.
But, suspect they should be good for a number of miles yet.
Ya, I see you installed them in May of 2010. 'Blue Book' shows you were around 148k. Yours/mine has 170,000 miles now. ^.^d
I would think they are still good,for peace of mind remove the easiest one completely and see how it compresses.
All Koni shocks should compress EASILY. The vast majority of their dampening is on EXTENSION. So, pushing down to compress should be very easy. Pulling to extend should require a lot of force/time.
That is because dampening on compression adds to effective spring rate, adding to harshness of ride.
Dampening on extension is not nearly as "harmful" to the ride quality.
Interesting point Brett, that rebooted my brain. Since most of our coaches have variable air spring rate somewhat controlled by the orifice size in the ride height valves I am thinking. This I would think would offer a boatload of suspension tuning opportunities. How close do you think that the factory got it right? Any known tips or simple mods might be of interest.
I think there was a five second delay built into the ride height system. Zero delay was the older design. Yes I asked those questions then also.
If you really want better handling remount the two rear ride height valves to the front. One in the year.
That was how it should have been built according to mr Neway. Foretravel used a trailer drawing.
I was there when we had him advise on suspension long ago. Old guy with a cigar
Wouldn't having the two ride height valves in front cause twisting?
The rear is much heavier and to lift it from the front would torque the chassis.
Without knowing a LOT more than I do, I would not rearrange where ride height valves were located.
I am fully aware of coaches with 2 in front, one in the rear and aware that they allow for less lean on cornering (the outer front side's air bags "hold" rather than send their air to the other side).
There is even one chassis designer (Gary Jones) who uses 4 ride height valves-- one for each wheel position.
But, again, this is not something I would suggest a shade tree mechanic (even a good one) "redesign".
Brett, wouldn't 2 in front and one in rear suit a front engine coach? Is that the ones set up that way?
Chuck,
I have not worked on any FRED's.
But with IFS, I have seen it.
And on the Peak chassis (Gary Jones) used by Alpine, there are 4. I don't know what Gary is using on the Powerglide chassis he designed for Tiffin.
As the saying goes "if it ain't broke don't mess with it" Our setup works fine.
Tripods are more stable many times than four legs.
Agree that a tripod might be more stable but that stability is a equalateral triangle,have seen some Safaris with 2 footings in back
and 1 way up front that would be more stable with 4.
Some busses also had 4 valves. You had to make sure you were not torqueing the shell as was mentioned.
"Active air" has large diameter lines to quickly effect the coaches lean.
Here's a five dollar phrase I'd not known about Koni: FSD means "Frequency Selective Damper." :dance:
A std shock uses a series of washers that are bent up over holes in a series of stacked washers. As you pull or push the shocks piston through the pressurized oil depending on the speed of the pistons movement the washers flatten over the holes.
Different speeds block different holes.
Apparently the fluid displacement different flow rates through a single set of holes over time either wore the washers or broke down the oil or both.
So Koni built two separate circuits inside one shock body. Separate low and high speed circuits. Less wear. Longer correct dampening. Lifetime warranty
My $1100 Penske bike shock has separate adjustable high and low speed compression,and rebound circuits that I can change while riding. Bunch of different dampening curves some quite complex and even lopsided. Lifetime warranty kinda, about $150 every 4-5 years to have it feshened up. Or if you've put on so much weight that you've run out of adjustment.
Back to the subject kinda, the time delay is required otherwise the air spring and ride height valves would be fighting the dampener (shock) it will still try to fight it but at a very slow rate. Probably not much to be gained in typical corners with 2 air valves in the front. Would help during substained cross winds, or tilted roadways.
Next ? When my ride height valves need replaced are they standardized one size fits all deal?
We had a 34' Safari with the tripod levelers (had four previously on another coach). With the 4 position setup, one corner could be holding less weight and you wouldn't know it. With three, the weight is more evenly distributed. This was much easier for us to set up (level) and we found no stability problems since the wheels must maintain contact with the ground. Think about building a chair vs a stool - which is more likely to wobble. Not sure how the conversation went in this direction.