Mole

I have just spent four months with a set of s03 pp on the back and oem so2s on the front and talk about crap handling, bump steer the lot, went back to oem s02s on the back and transformed the car back to normal. I will never cock around with other tyres again. I felt the walls of the s03 pp against the new oem s02s they really have some play in them compared with the s02 which were very solid. Plus I only got 4000 miles out of the s03 whilst I got 11500 out of the original s02s. Its not ideal to have two different types of tyres but I wont mess around with it again. This car seems very sensitive to changes.

Frenchie

I think you hit the nail on the head there, Colin. I put 245/45 F1 Eagles on the back and S02's on the front and, like you, found the handling to be crap. However, as soon as I put 205 Eagles on the front as well, all came right again. Plus the wet weather performance is superb.

Mole

I made double the cock up by putting 225 s03pp, so I had undersized tyres on aswell. Expensive lesson.

Kobe

I'm also wearing same t-shirt.

Mole

Just out of interest what do the eagles look like on the car. I really like the look of the s02s as there are no ridges on them and they look quite wide. I know I put so3 pp that were slightly undersized but they looked crap.

stevenleith

Thought i'd post this onto this thread as well as it'll probably be more relevant here!!

IMO i think there are more bump steer issues than people are making out. I have just put the F1s on all four corners and am currently playing with the psi to find an optimium balance for the roads that i drive on. But since i have had my car back and had the F1s on i have experienced incredible bump steer - not very nice at all.

The car hasn't felt anywhere planted enough going over adverse camber and bumpy corners at low low speeds - i mean feeling the WHOLE car moving to the left or right going at very low speeds is just getting very tiring.......

My tyres are currently at 33 all round to try and counter some of this - but i have found that at higher speeds on the motorway going round progressive bends the car is drifting.........even in the dry - so in this case i need the psi higher to give more stability.

Pete has his F1s up at 36psi which would only make my bump steer worse......so i don't really know which direction to go in. I'm hoping that the UK alignment adjustment will help eradicate some of this as well......

Frenchie

Excuse my ignorance guys but what is "bump steer" exactly

Tonky

'Bump Steer' is the tendency of a vehicle to react to bumpy surfaces by deviating from it's steered course, usually manifested by the rear end jumping sideways. Many people who race and track the car believe the S2000 has this tendency. Others who also race and track the car do not believe it has the tendency. Most who experience it, claim that it happens pretty well at 10/10 of the cars potential when being pushed competitively, although they declare it can happen at lower speeds on bumpy surfaces.

Most luxo barges have a sufficiently compliant chassis and suspension system that they will absorb anything. If the S2000 has this tendency, then surely to a large degree it is to be expected from a lighweight car with such a rigid chassis and sporty suspension set up. Steering/tracking alignment adjustment could well be a big influence on this tendency.

Whilst I would never attempt to drive at anywhere near 10/10 on public roads, I certainly don't hang around given the opportunity and a clear road, and I don't believe I've ever experienced any undue bump steer in the car. Perhaps a lot of this is down to individual driving style. I think anyone who is unduly concerned about it should definitely be looking at an alignment check before they do anything else. There are aftermarket front and rear sway bars available which may be found beneficial.

Frenchie

This item is from a parallel thread

[QUOTE]Originally posted by UKjasonm
[B]We have some speed bumps on the road near where I live and unless I go over them directly through the center (there are two seperate bumps in the road) then the car can

stevenleith

Surely at some point you have gone over adverse camber or very poor tarmac round a bend and felt the car skip to left or right?? I get it practically every day! I find that whenever i go through road works etc...i get some kind of bump steer....but as you say.....with hard suspension on a rigid chassis you have to expect it to some degree.

I'm not so sure how driving style can alter low speed bump steer - it is simply the process of going round a corner, driving over a sh*te piece of road and feeling the car skip a few feet left or right.....theres nothing you can do about it when driving through that piece of road.....the rear wheels cease firm contact with the road surface and the car alters its shape.

I never equated bump steer to actual "speed bumps" - surely these should be taken at 10/15 mph in a straight line - and shouldn't really induce significant bump steer. It is cornering that'll induce it.........where the rear steps out of line with the front thus causing sudden over/under steer.