semi slick tyres legal or not?

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naki lad
Posts: 9
Location: taranaki

semi slick tyres legal or not?

Post by naki lad » Thu Sep 25, 2014 4:23 am

Right been on Google and a heap of forums and can't find a straight up answer, bought some alloys and they have Bridgestone potenza semi slicks on (didn't realise before buying lol) are they road legal or not?

Like I said a lot of forums ive crossed have been saying yes and no, a friend that runs them on his road legal track car says its down to the mood of the police officer that pulls you? Surely they are either legal or illegal regardless of how the cop is feeling at the time.


ALSO.. where can I buy rear camber arms for a 300zx? Are other Nissan car parts interchange able for lowering / camber on the 300zx?

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Andy
Site Admin
Posts: 2020
Location: Auckland

Post by Andy » Thu Sep 25, 2014 11:42 am

Not absolutely certain but pretty sure DOT rated with more than required minimum tread are road legal. Most semi slicks become illegal quite fast because of tread depth.
Last edited by Andy on Thu Sep 25, 2014 1:01 pm, edited 1 time in total.

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ZILVER
Posts: 470
Location: Auckland

Post by ZILVER » Thu Sep 25, 2014 12:58 pm

Are they Bridgestone Potenza RE??
There are a few Potenza varients - most are street legal.
I've RE-11 fitted to my track car- they are excellent street legal semi slicks - VTNZ WOF was no problem.
RE11s have superseded the RE55s if I remember right were semi-slick designed/legal for track use only in the Potenza range - RE55s will not get WOF here. (Rather if used on the course road will destroy themselves quickly due to very soft compound)
You'll probably find on some foreign forums claiming RE11s are not street legal - but this I believe is only applicable to certain countries.

I can supply new rear camber arms from ConceptZPerformance in a club bulk buy due to USA leave next week. Please PM if interested
(Unless going aftermarket/adjustable you'd want new OEM types as the bushings are sold with it pre-installed.)
Adjustable arms for the rear maybe similar to skyline. However the front arms are Z32 specific.
(I've read that skyline upper arms will not clear by 3mm/causes impact damage over time)

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Baker93
Z Club Member
Posts: 331
Location: Auckland

Post by Baker93 » Thu Sep 25, 2014 9:27 pm

Dot rated tires are in theory road legal hence the DOT rating. I have not checked for some time but the NZTA guideline for tire tread depth used to state that a tire must have a tread depth of a least 1.5mm within all principal grooves that contain moulded tread depth indicators and around the whole tire Blah blah blah.
For those that do not have moulded tread depth indicators the old 1.5mm tread depth across 3/4 of the tread width applies.
In theory DOT rated semi slicks comply and are indeed sold as original equipment tires on some hipo cars. ( check out some of the Michelin Pilot tires)
Some other DOT rate tires such as Toyo R888s would make fine dry weather tires or are even ok on damp roads but that is all.
Other DOT tires such as Hoosiers and some Hankooks are best described as slicks. Needless to say these are a death wish on a damp road.
In summary most DOT rate tires make terrible road tires ! Not only due to poor wet weather performance but also due to there carcase construction, wear and tendency to tramline etc etc.
In my view they are road legal, but good luck arguing the point.
Personally in NZ you want the best wet weather tire you can get ! In 99.9% of dry road based driving conditions most people get nowhere near the limits of their tires and are unable to tell the difference in adhesion levels between different brands of tires.
Keep the DOTs for your track days.

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