Hi,

It's been a while since I posted on this forum. Sold my seven a few year ago now and started to build a Cobra... well 3 years on and I'm finished and have 1 thing to fix on the IVA failure list. The issue is around self-centring -oh yes that age old problem with kit cars. My Caster angle is as big as it will go and someone suggested that my wheel offset might be incorrect on the wheels I purchased (ET 21mm vs ET 35mm for Sierra wheels). My original Sierra wheels have long been sold (doh!), so I have no way to check whether this is the problem - and none on ebay close enough to me.

So, my question is does anyone have a spare set of sierra wheels they can sell me or even lend me for a weekend - for a small fee of course :-)
Anyone out there within 50 miles or so of Southampton that can help?

Thanks!
TimN

I've got a set of sierra build wheels, they are steels but might do the job.
Free to collect if you fancy a trip up to Northampton (nearer Wellingborough).

Mike

I dont think increasing the track, which is effectively what you have done, would have any effect on self centering. Try pumping the tyres up?

Increasing or decreasing the offset will have a marked effect on self-centring.

What you are doing is increasing the distance between the tyre centre-of-contact-patch and the steering centre (the point at which a line drawn between upper and lower ball-joint intersects the road surface).

The drag force (created by the movement of the tyre over the road surface) acting at the tyre centre-of-contact-patch will operate at a greater off set from the steering centre and will therefore create a bigger self-centring torque (force x distance = torque).

Good luck finding some wheels

I even googled to make sure I wasn't missing something before posting that!

Thanks Justin!

duck, if it's any consolation, I also googled it, but after hearing first hand that someone on the cobra forum had the same problem I started to investigate it. After increasing my caster angle, pumping the tyres, setting the camber and toe in, I was getting desperate.

Mike. Thanks I may take you up on that unless I can find something a little closer :-)
TimN

No problem, they are not going anywhere

I've got a set of sierra steels, I don't know if the tires are any good. They are in rowlands castle (other side of portsmouth).
You can have them if you can't find anything else.

Thanks for all the offers. I found a set on ebay! After much measuring and testing I found that it wasn't the wheel offset that was causing the problem, but the Toe-in. It wasn't out my much, but enough to stop self centring. Anyway, all fixed and IVA passed. Now while I wait for Mr. DVLA to process my docs and send me my v5, I'm selling off all the old stuff I no longer need - including the wheel (with good tyres I have to say!) - All listed in the For sales section and on ebay.

Thanks again guys!
TimN

Congrats on the IVA.

Holding my breath for registration from Swansea myself.
Yesterdays phone call was answered with :- we are just processing forms received on the 9th April..

Thanks!
I passed on the 9th April (and had my application in the post on the 10th), so maybe they are processing mine next :-) From what others have said 3-4 weeks is normal. When did you make your application?

TimN

Hi Tim,
My application was signed for on the 16th April.
Is the 4 weeks total time or from when they start to process it?
She said Easter and sickness was the present cause of delay.

Sounds like yours is just a few days behind mine. From what other have said (and I believe it does vary), it is 3-4 weeks from when they first receive it. So I'm hoping for early May. I'll let you know when it arrives. Hope my new steering wheel arrives first - I really don't want to be out in a Cobra with a Sierra steering wheel :-(

Roll on the summer :-) !!

That's encouraging - sort of....
It will be great if you let me know, it may help my
frustration... this has been the only time in the
build that I am getting proper impatient.

quote:

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Originally posted by avagolen
That's encouraging - sort of....
It will be great if you let me know, it may help my
frustration... this has been the only time in the
build that I am getting proper impatient.

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