Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Workshop Note - Bump Stop assists

The problem with the OE solution of limiting suspension travel by fitting a chunk of rubber under the 'hoop' for the Differential casing to hit is flawed from the off...

The hard rubber pad is not progressive
(it was not even fitted during build on my previous S1 Roadster)
As we all know the axle is highly unlikely to travel an equal amount each side as it hits a bump, ie stay horizontal
So, in real world driving, by the time the hoop bumpstop limits travel, the wheel travelling up into the arch will be allowed to go too far up hence the witness marks in peoples photos
This also concentrates much more load onto one sides leaf spring & shock absorber (I have seen shocks bust the internals as they bottom out)

Rogers solution addresses this by being both progressive and limiting travel independently at each end of the Diff

My 4/4 Duratec also had this very hard kind of the RUBBER inder the "hoop" . Fittet from MORGAN (more something like plastic).
Absolutely useless...
So I changed this part to Rogers....

That makes sense, thanks for this deeper explanation!

A well-known feature of Konis especially, dating right back to the mid 1970's when we used to fit them to our Triumphs. Bottom out a set of Komis and you'd often bust the adjuster mechanism. We used to set them on the hardest setting and reduce them click by click until we got a ride that was tolerable to avoid the risk as much as possible. Mind you, that was in the days when we still thought that hard suspension was best for good handling - which I suppose was understandable given the soggy UJMs that were around at the time.

WOW!! Actually, Tim I had no clue. So thank you, the light dawns now. Others have had trouble believing your tale below as well, even as they were trying to explain. For me, I was a friend one day and horrible hysterically treated despicable cretin the next. Yes, I found your reaction inexplicable and still do. Is that what your 12 years of high hostility about GoMoG and me is all about?!!!!

To flesh out the background, as a service the adherents, I would post events and occasionally birthday wishes. When you announced your birthday party to the entire group on emog..which at the time virtually meant to the entire Morgan world, I added it to the events page as a courtesy and in an effort to make your event the success you wanted it to be. Doesn't this forum do the similar things??!!!! eMog (bless its memory) was no more "private" than this forum/ the only other rule being that real names were used rather than monikers like "Hamwich" and "gomog". I found that people are more civil when they use their real names on forums..and if they don't like that, they can use fake names as many did.

Frankly, it was for the best I guess. eMog malcontents went to the Naughty Boys Club (emog did not allow foul language and apparently there was a segement who belived that was necessary).) and eMog had supported TalkMorgan from the start. There was nowhere for an Aero owner to go to!

Nope. Your story doesn't pass the smell test. People who are desperate to keep an event quiet do not post it to a forum with many 1000s. In any event, are you suggesting that I, a old friend, repeated your announcement of your birthday with insidious intent?

Hi Copperman,

As Roger noted, bump stops are not part of the suspension function. They are there merely to protect (slightly) the ravages of the impact of metal on metal in extremis and make crashes into thuds, admittedly an improvement in sound effect. Roger, on the other hand, explains that his adjustable...suspension aids are PART of the suspension. I assume that his and all other users have perfect leaf springs, easily determinable by merely measuring the ride height at the rear. In fact, why don't we do that..measure the distance of a common point at the rear to the ground? That is going to surprise many here.

Don't let unnecessary science obscure simplicity. For almost 70 years, Morgans with Factory springs in unsagged and otherwise good condition did NOT produce a car that bounces and crashes down roads. I have had famed moggers that we all know, drive in my car and exclaim that I must installed independent suspension, but I have done nothing but adjust the stock components to operate precisely. If our cars did not function as such, my wife would never have tolerated months at a time in Morgans on back roads. So Morgans can be great at the back (where all the comfort is) with the right equipment and properly functioning components. She will quickly say that the most comfortable car she has ever driven in is a Morgan!

From this perch, the major problem seems to be that this community, with generally more modern mogs, have grown up during a long era of substandard leaf springs.Look how many times the MMC has changed leaf spring suppliers since 2005! Does that not indicate something? They were aware of the problem, just couldn't find a reliable supplier.

We can.

Lorne

Any measurement from the ground to a point on the rear wing will be influenced by wheel & tyre size.

A more consistent measure is between the high point of the wheel arch to the wheel centre.

But even this includes variable rear wing arch curves.

Peter Ballard's idea of the distance between the bottom of the axle and the chassis stop is probably most consistent, but not so easy to measure.

On my original contraptions I did used the original old BMC mini bump stops and they worked well. The weight of a mini is not that dissimilar to a Morgan. Contraptions MK2’s use better performing elastomer. I also took the opportunity to squeeze in something bigger with an increased working range. Both version stiffen the spring rate towards the limit of the movement but the later version are even more progressive.

“Do they significant shorten the suspension travel?” I would guess it depends on how precisely you choose to adjust/tune them to the specific car and control the vertical movement. But is this a good or a bad thing? We would need an expert to answer that but for me if they enable the use of softer rate (more comfortable) springs on my car without the fear of body contact then it’s a good thing

However I don’t know how shortening or controlling the vertical movement might affect cornering….

Hi Roger,

I woke up this morning with a sudden greater understanding of your thingies. (I call everything on a car a thingie and these days, I often wake up with an epiphany these days..odd how the mind ages!)

We both start off at the same conclusion. Many Morgan trads, made after the leaf springs curse began (best I can tell that was I had the start of m run of bad new sets in 2005 and after my 2002 was made), are sadly wanting at the rear. We both came to that conclusion and came up with an action plan, me with replacing springs until I finally found a set was defect free and you looking for an addon that supplemented or, de facto, replaces the springs with an adjustable systems based on a progressive rubber cone.

Your solution is very cool.... I like the adjustment feature. Air suspensions do that and Armstrongs (oil used or their select-a-ride had that feature with driver control on the fly) I also like the ease of installation. And I adore owner ingenuity!!!! Essentially, you have found way to compensate/substitute for a major defective and widely failing component which became a large part of Morgan production before your car was made.

What saddens me is that [b]all this would be unnecessary if the original component performed as it should [/b] as they always did before the leaf spring plague began. There is something else, by leaving the classic leaf springs, we lose a LOT of unseen leaf spring sophistication. I say unseen as it is IMPOSSIBLE to quantify the the suspension of any trad Morgan because of the flexing frame and its infinite variants. It would have to be done car-by-car. The tables and graphs and formulas can only apply to a component on a Morgan, not the end result when installed in the car. Those who suspension tweak THEIR Morgan individually have great success..those who buy one-size-fits-all have wildly varying results. You dodge that problem with your adjustability. In any event, in my experience, I have found very little is necessary to make a Morgan suspension feel sublime. But this lack of a source for proper leaf springs at the moment is a big problem, especially when it sends fine brains like yours to the drawing board looking for an alternative to the oldest, most reliable, suspension system for want of a decent part.

It is a current canard that we have been convinced of that coil springs are more "modern". They are merely cheaper. Leaf springs and the work the do offer more ride-shaping and are normally far sturdier. IMHO, they marry with the Morgan flexing frame to create a sensuous ride, assuming all is as it should be....which is so rarely the case.....Morgan owners too often tolerate the intolerable) I do not argue with magic. If leaf springs work with a flexing frame, I am all for them

My greatest fear, considering the number of leaf spring suppliers Morgan tried in that short period, is that something changed in the cars that makes leaf spring fail, but I dismiss that as impossible. Leaf springs are notoriously sturdy. The ongoing supplier failures for that long a period mystifies me.

Lorne

I replaced the original leaf springs on my car (not a Morgan) when it was undergoing a mid-life refresh a few years back. The new springs were almost flat after a year.

So - I sent the originals off to be refurbished and re-tempered, refitted them and they're still fine some years later.

Unfortunately I can't recall where I sent them !