Sewing Machine?

[Avalanche]

Have meant to ask this for a while >90mph my Tuscan starts to vibrate thru the steering - well more like throb(!) on and off, on and off, continously... Let the jokes roll in! It's always been like that, becomes less profound >110mph. It's akin to the throb of an XBox gamepad mimicking Harry's heartbeat in Silent Hill when he's a bit low on health. Same thing - the steering pod on the Tuscan throbs too at speed...

Is that part of the sp6 sewing machine phenomena? It doesn't bother me intensly but wanted to know if every Tuscan does that?

p.s - changed my name cos I couldn't fit SwissCheeseGrater as a nickname. It was a bit crap too.

[andyvdg]

It's either :

Tyres need rebalancing
Wheels are bent
Suspension is out of aligment

Cheers,

Andy.

Editted to say - it should be nothing to do with the engine.

>> Edited by andyvdg on Monday 6th September 11:09

[Avalanche]

ah...will check, thanks!

[TSS]

Some pod wobble at speed is pretty normal and a lot of Tuscans get it. But the steering wheel wobble/throbbing sounds like exactly the same problem that I used to have, most noticeable between about 90 and 110, and very annoying.

It took me ages to get to the bottom of it. I had my wheels balanced several times at a variety of tyre fitting places, suspension checked, wheels checked, new brake discs, engine mountings checked.

In the end it was down to wheel balancing. The balancing machines at normal tyre fitting outfits like ATS are just not good enough for 18” wheels running low profile tyres on a car like a Tuscan (and are often operated by monkeys). Silverstone TVR took the wheels to somewhere with what is called a “hunter balancer” machine. It has some sort of replica hub to bolt the wheel to, rather than just a central spindle. It also places the wheel on a rolling road and simulates the pressure of the weight of the car pushing down on it. The result is a very well balanced wheel.

This cured the problem on my car. Probably worth giving Matt at Silverstone TVR a call and discussing it with him (01327 855772).

[basil brush]

It seems to be common with Bridgestone tyres as well for some reason. A few owners have said it stopped when swapping to Toyos, and mine went away when I swapped to the goodyears.

[J_S_G]

Have new, balanced tyres (done by a standard place - Goodyears on the rear, Bridgestones on the front), new(ish) Nitrons fitted by Joolz, and a full laser alignment done last week. Still get it at 90-odd MPH, but nowhere near as bad as before. It was "really annoying", now it's just "noticeable". Think a proper rebalancing might be in order at some point...

[Avalanche]

Andy - you were right: bent wheel (visibly from the inside!)

[Avalanche]

despite the bent wheel - the rebalancing sorted out the bad vibes/"throbbing".
Nice and smooth now.
Thanks for your input.
Case closed!

[mcspreader]

The fact that your steering goes wibble at a certain speed and then comes back in as speed increases points wheel balance. The exact speeds vary with diameter of the wheel/tyre but it would seem consistent with the symptoms. Brake disk imblance ,because of small diameter/mass happens at much higher speeds before it is noticeable. (The problenm is there lower down but not evident unless you are test driver.) Suspension problems are not so related to speed in the same manner. They do not tend to diminish with speed in any noticable way. In general Tuscs go wibble in the suspension on slower roads at bumpy speeds. Anything more they throw you into the geography unless Nitron or Schumacher take an intervening step.
NOTE! A number of small otherwise insignificant problems with natural frequency of movement can be dangerous if only two match at any speed. This is only likely across a very narrow speed band.
EH?
Balance your wheels! Properly! No Quickfek!