Bumpy ride ! :(

[Oni]

Hi All
Im a new poster on the forums but a lurker for quite a while. I brought a 1990 NA6 ( so i was told in the chat earlier! ) today ! and i noticed that on bridges and sometimes on highways that its quite bumpy. im going to check my tyre pressure tomorrow and make sure its correct. The door says my tyres should be at 26psi.
If this fails to help anyone have a hint on what a complete car novice could look at to start correcting this? Thanks all!

Oni

[Juffa]

Hi Oni, Welcome to the obsession. How many Km has she done? If the suspension is still original there is a good chance that it is well and truly past the use by date. You have many choices from keeping the original springs and upgrading the shock absorbers (yes Casey I know!) to something such as Koni Sport (around $1k new + fitting) to replacing the shock and springs with a Tein, AXG or Bilstein setup, from around $1.5k +
And then there is the suspension bushes. The original ones are rubber and over time will become quite stiff which gives you are jarring ride. Replacement is around $450+. Start with the tyre pressure (suggest 28 psi), get a good wheel alignment and see how this feels. Oh, as she is a 1990 she should be wearing 14 inch rims with 185/60/14 tyres, if they are bigger than this you may have heavy aftermaket wheels which can also affect the ride quality.

J

[Oni]

thanks for the reply!.
Its dont 170,000 k's, and it has 15\" alloys on it so they might not be helping. I would guess that the suspension is still all completly original. I dont really know much about cars im the person that use to thing cars were from a to b but now im much changed!.Hopefully soon i can boast at being able to do more than check my oil / water ;). Thanks for the tips i hope the suspension doesnt need replacing thought. My tyres are almost shot and i was thinking about getting new mags ( curent ones are a bit rough) and suggestiosn on weight/width for 40ish k's a day 70% highway driving ?
Thanks again

Oni

[NMX516]

There is also the \"65mph shimmy\" or whatever it's called, which can be a problem on the early model cars. Basically, these cars are very sensitive to poor wheel balance, so at about 100 - 110km/h the car can start to vibrate noticeably. Get a good wheel balance with your new tyres and it should solve that problem if in fact your car does suffer from it...

[Oni]

thanks for the tip NMX516. I think ill do just that. it did also get a fairly noticable vibrating in the steering wheel once i passed 100km/h. im guessing i have quite poor tyres at best and they probibly havent been balanced. Would you suggest getting one done on my current tyres knowing they have about 6months tread on them? or wait for new ones. i dont mind going a little slower, im never in a hurry, but if it could be damaging the car ill get one asap!.
Thanks


Oni

[Okibi]

Oni, join your local MX-5 club, then you can get a member to take a drive in your car and tell you what is \"normal\" and what may need to be fixed.

[Garry]

Old worn down tyres always ride more harsh than brand new ones. So new tyres will help you out a bit.

Have a look under the car. If your shocks (dampers) are black then there's good chance they are the originals. Bin them and get something better. Even just replacing the shocks and retaining the original springs will transform the handling and ride. A few guys have scored some KYB AGX adjustable shocks from the US via Ebay for around $400. These are great shocks for the money.

[NMX516]

For $40 or there abouts maybe, for a wheel balance, I would get it done if the new treads are 6 months or so away. It would annoy the shite out of me in no time if I was doing 70% highway driving. Plus, the vibrating can't be doing parts of the car any favours, just wearing it out prematurely in my opinion. Having said all that, worn tyres can be difficult to balance accurately, (depending on how they are worn) so trying to do so might be a fruitless exercise.

[manga_blue]

Oni, join your local MX-5 club, then you can get a member to take a drive in your car and tell you what is "normal" and what may need to be fixed.

Okibi is absolutely right, Oni. The MX5 clubs are by far your best starting point for advice about the car. Links to all the clubs are halfway down this page.

http://www.mx5vic.org.au/mx5vic.org.au-asp//links.asp

They cater for all ages and all interests (in MX5s of course) from social touring through to racing. There are plenty of members who are experienced with the cars and are willing to help new members.

[AJ]

Oni is a Taswegian............i don't think they have a club do they??

[Oni]

Thanks guys, ill see if there is a mx-5 club in tassie . I checked the tyre pressure when i got hometoday and 3 were 40psi and one 35. i made them all back to 28 so ill know tomorrow how much thats helped!.
Thanks ill keep an eye out for shocks if i need them. ive only seen 3 mx-5s within a 2 hours drive of where i live >:(

[manga_blue]

Oni is a Taswegian............i don't think they have a club do they??

email Bill Campbell, Membership Officer of the Vic MX5 club, at membership@mx5vic.org.au

[Oni]

Thanks for the advice all. I checked the type pressure and was supprised by what i found. the 2 back were at 40psi while the front left was at 35 and the front right was 40. i have put them all back to 28 and its alot better now. !!

Oni