Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Terminal understeer.

I suppose that terminal understeer is inevitable, given the narrow tyres and heavy engine and transmission at the front, and on a couple of occasions I have been very grateful that I haven't been going into a corner a tad quicker, as I would have left a Three Wheeler shaped hole in the hedge, and watching this Fifth Gear video: http://www.youtube.com/watch?v=t8yYqwa_O2U really brought home to me just how much understeer our little cars do have.

It is probably a fruitless question, but has anyone had a chance to either reduce this understeer or even had any thoughts as to whether it can be done? I'm thinking the most obvious way is to use better front tyres, but maybe the suspension set up can be changed too?

And, please, do not reply saying that it should be driven slower into the corners - I already know that.

Enjoyed that!! Wow - they almost tipped the M3W over!!!

The Atom seems a beast!

Tiff was driving like a baboon and of course it was going to do that! As you say Paul, understeer can be quite prevalent on our cars, but it can be 'managed' I think, in a number of ways. Better grip from the front tyres would be a start and I am keen to try those Blockleys next, as I hear good things about them. Provided they don't produce too much kick-back through the wheel on account of their stiffer sidewalls (less of an issue I'd have thought for you - and soon hopefully, me - with that excellent re-engineered front suspension), then it would be a good move.

Ironically, the rear tyre needs to produce less grip and I for one won't be looking to replace it, come the time, with anything other than a hard-as-nails touring tyre with less grip than more overtly sporting rubber. To put something like a Toyo R888 on the rear would be hopeless, as you'd remove that lovely balance, doughnuts would be harder and you'd be far less able to make the rear move a little more relative to the front. Bad move all round that would be I think.

We had a very spirited trip to Germany and back in September and I was obliged to concentrate very hard on making 'good progress', on account of the other machinery in the convoy (TVR Chimera, Lotus Evora, Lotus 340R, 2x Caterham Se7en's) and it did take quite some focus. But with careful use of trail braking to keep the load on the front end, blending out as the lock goes on, gave excellent results. I have to say that under those circumstances, bumping up the front pressures to 28psi makes a heap of difference too.

That scared me when I first saw it (and still does!), especially because Tiff is quite tall for a racing driver and was not wearing a helmet.

Of course, you rarely generate the same forces on the public road that are possible on a race circuit, but even so...

Also, even a four-wheeler can flip when coming back onto a high-grip surface from wet grass at the wrong angle.

I am still running in my M3W and often find that I have to back off or change up just at the point where it might be possible to go neutral or even into oversteer with a heavy application of throttle - and I am not even sure if it is possible.

As most people on here will understand, if you have too much grip in a three-wheeler, stability can be reduced, perhaps to a dangerous extent.

It is interesting that Chris Harris, in his video last year, was able to oversteer the 3 Wheeler impressively on the public road. Chris is a very fast and highly competent driver, like Tiff, but I wonder if that was because the car was on the early setup, with Suplex dampers (I do not know if it was or not).

In any case, there is not a wide choice of front tyre, as far as I am aware. Perhaps more power is the answer - or reduced grip of the rear tyre!

The Blockleys make a fair old difference as does a bit more pressure. I ran them at 25psi through the summer but might drop it a tad for the winter - last time I was out on cold greasy roads there was a bit less feel from the front than ideal.

As a person I'd never lend a car to, Tiff is one.

On a vintage three wheeler, with the same size front and rear tyres, there is a way out of understeer. You open the throttle further. I've got no idea if this works on a five speeder, and the public highway is not the place to find out. It's also very counter intuitive.

Anyone trying this, I'm not recommending the manoeuvre, merely observing.

Interesting, I wonder if opening the throttle actually decreases grip at the back and therefore the car will go into oversteer mode, requiring fast application of a "dab of oppo"! I would have thought that if the rear tyre grips, it just pushes the front end even more?

Opening the throttle, progressively, as you drive out of a bend will always settle the car better in terms of driving stability. If the surface provides relatively little grip, then the rear will begin to slide - progressively if done properly - increasing the degree of rear slip and counteracting the understeer at the front. Get it right and the car will enjoy a neutral drift, which can be perfectly safe in the right hands. Get it spot on and you'll do a Chris Harris, as he is very good at that kind of thing!

EVO magazine put the M3W into their Car of the Year 2013 contest and part of this was running on both track and roads.

They said that to counteract the understeer you counter intuitively need to go harder into the corner with extra steering lock. This seemed (to them) to encourage the car around the corner.

I've not tried this and suggest some careful experimentation on a very open corner or track with safe run off!

In the past I have use to good effect "tyre softener" from D.Tweeks. This may make the Avons slightly softer and give a little more grip.

Years ago I was taught by a very good driver, he has won Le Mans 24 hours in GT2. to imagine a piece of string attached to the throttle pedal and the steering wheel. So the more steering lock that is applied the shorter the string so less throttle travel.
This equates to, as you start to straighten the wheel up coming out of a corner the further the throttle can be pressed.
I find this method gives smooth fast exit speeds with no oversteer.
After a while it becomes second nature, as I turn the wheel my right foot comes up and as I straighten up it goes down.