When fitting the adjustable tie bars a few months ago I also added the mini spares recomended poly bushes on the outside and regular rubber units on the inside. The suspension guy who set the camber/cast. insisted that doing the tie bar end nut all the way to a point where the bushes seemed very compressed was neccesary.

Now just a few months later the rubber tie bar bushes are worn out and about to perish (poly still alright). Any possible causes?

I have a set of those on my car, and I didn't tighten them up quite that far. I have them with a slight bulge in the polyurethane bush, which doesn't deform the rubber one too badly at all.

There's still plenty of tension on the nyloc nut, so there's no risk of it coming undone...

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Simon

The adventures of an owner builder in the Tallarook Ranges

Well I always did my up to tight but not all the way but when getting the adjustable tie bars the suspension guy insisted it has to be done all the way to the end - I had a problem with that as the bushes were distorting and I thought the lock nut is there so that you wont have to do it all the way - but he's supposed to be the expert - any deffinitive opinions?

The tiebar is designed for the nut to be done right up, with the original rubber bushes. The nut is nyloc so it won't come loose, not to allow adjustment.
Another prob with poly is if you fit a full set and tighten up, you can bend the tiebar as it's too flimsy for the stiff poly bushes..
Personally I've had more joy with rubber bushes there than poly- same goes for the lower arm inner mount. Cheaper too.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Hmmmmm..........The ones on the car when I got it (the bent ones ) had an ordinary nut and a hole through the rod with a split pin to stop the nut coming off. - guess I'd better get some nylocs

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Anyone ever done the math to figure out how many threads equals what effect on caster?

Doc, theyre minispares adjustable arms (heavy duty double thickness too) so I used a the poly bush on the outside and a rubber bush on the inside as per the minispares instructions - just didn't expect the bush to perish so quickly.

You've fitted them correctly, I just think your suspension guy has done them up too tight. The bushes are there to control suspension movement under acceleration and braking (hence the reason for the polyurethane outer bush, it's much firmer than rubber and won't deform as easily, reducing directional instability under heavy braking).

There's no point in doing them up as tight as you can -- once they're tight enough to control the suspension you get no benefit in going any tighter; all you're going to do is deform the bushes and reduce their lifespan.

The nyloc nut (or split pin, I've seen that done too) will prevent anything coming undone, so there's no need to put 100 ft-lb's on it

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Simon

The adventures of an owner builder in the Tallarook Ranges

I'll be doing this on my car soon, with exactly the same parts. I'll let you know how I get on at the suspension set-up shop.

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'98 Mpi Sportspack + 7 port alloy head

all manuals i own:
torque wrench setting: tie-rod to subframe 30 Nm / 22 lbf/ft

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Rover 214 atm ....

Yeah, I was just illustrating that it's not necessary to wind them up as tight as they can go

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Simon

The adventures of an owner builder in the Tallarook Ranges