Lotocones

[69S4]

Firstly, I'd just like to say hello. I'm a long term reader but very infrequent poster, mainly because everyone else seems to have a much deeper knowledge of the cars than I have despite owning my S4 Elan since 1982.

I've been doing some work on the rear suspension recently and bought a couple of new Lotocones from Mattys, but it looks like the old ones (from circa 83) are different from the new ones. The new ones will fit and do the job but the ride height will be an inch or so higher -and it was correct before. Is this what current production Lotocones look like and I'll have to lump it or have I got the wrong one?

Picture attached if I can make it work

[paddy]

The ones I fitted recently look like the one on the left.

With your existing one it looks like the conical part in the middle that the spring seat fits into has vanished or was never there. So what is happening with the spring seat at the moment? Does it just sit against the bulk of rubber around the outside?

Paddy

[garyeanderson]

I think I got the new lotocone 4 to 6 years ago from Dave Bean, so they have been correct at least until your problem surfaced.

[ppnelan]

Is this what current production Lotocones look like and I'll have to lump it or have I got the wrong one?

The old one could be how they end up after (x) years or use...?

Matthew

[johnsimister]

69 S4 (what is your real name?)

I have been through exactly the same process with identical-looking old and new Lotocones. My car has a 2.25in ID spring conversion with aluminium platforms, and the upper platform was touching the outer ring of the original Lotocone just as Paddy speculated. So for me the new Lotocones were a very good thing because it meant they could now work as intended. The difference over rough road surfaces was huge.

However, the original Lotus rear spring platforms are presumably shaped so they don't touch the outer ring of the original Lotocone, or maybe there's some form of spacer between platform and Lotocone. I expect someone on here with original-type suspension could clarify. The new Lotocones work perfectly with the spring conversions and adjustable platforms that many Elans now have, but if you now have too much clearance between the Lotocone outer ring and the platform it's hard to know what to do to fix it. Can you modify the platform in some way?

I don't think it's a matter of the original Lotocone collapsing through age because the shape of the rubber still looks as intended. All that had happened with mine is that the rubber was starting to unbond from the outer shell. The shape and size of the central hole is different between old and new, too.

John

[69S4]

Wow, thanks for the rapid replies and sorry about the anonymous user name. I'm Stuart Holding, based in the UK (more specifically Thame nr Oxford) and I've had the car since the early 80's

I did wonder whether the new one would end up looking like the old one after a few years but the rubber would have to distort a long way
and there isn't much sign of it in the old one.

There was no insert with the older lotocone, the conical section just had the damper rod going through it. Without the spring seat the cone and the rod diameters meet about 3/4 of the way up the cone but when the damper rod goes through the spring seat first - as it would be on the car, the rod doesn't go far enough to jam in the cone as it's held on the underside of the spring seat.

The raised part of the spring seat has been sitting inside the cone on the old unit and there is about 3mm clearance around the edge. The whole thing looked about right like this but with the new lotocone the spring seat sits quite a way down from the top of the chassis.

From the pictures that Gary posted it looks as though I've got the right ones but if you bolt them to the chassis it doesn't look as though there's any need for the thin shouldered bolts as there's more than enough space for normal ones. Maybe I'm assembling it wrong, it was 25yrs ago when I last did it.

[bcmc33]

Stuart,

When I stripped down my rear suspension I found the Lotocones were like the ones you bought from Matty. I turned a couple of bushes to insert in the large bellmouth bore to make them work like the originals. The new strut inserts I fitted from TTR came with a spacer tube to match the main bore.

Susan Miller sells the original type.