Streetstock tyres..

[Sketchy_Racer]

One issue I see,

150 street stock the entry class alot of beginners,

Yep your right, so why are they trying to make it more expensive? Young riders can barely afford a set of second hand slicks, let alone $900 worth of TT900s..

A slick is designed for a warm track surface to offer the most contact patch to the ground and the tire is warm so sticks,

when its wet yu have a layer of water between your slick and your contact area of tarmac,

A slick has no grooves, so that the tyre can have as much surface area touching the ground at one time. that is reagardless of tempeature.

The fact of the matter is, 125s slicks are never going to get to optimum opertating tempeatures on 150s. alot of the tyre is unused and is acting as a massive heat sink for any temp that does get put into the used part of the tyre. Wet or dry, thats always going to happen. does that mean they shouldnt use slicks in the dry either?

When it is wet, you have a layer of water between any tire you use, regardles of what type it is!

A wet is designed to be used in these conditions,

It is cut and the compound is softer to grip at lower temps and speeds,
The cuts are designed to pump water aside for more grip level on the ground but also these grooves when water running through them cool the tire,

Personally, i think that the grooves in wets have very little to do with the 'pumping' of water. With the contact patch of a 50c piece, there aint going to be stuff all water in the way. Sure it would move a little but not much.

Without researching it, i believe that 90% of the reason that they put grooves in wets to reduce the amount of rubber on the tyre to be heated.

It's a lot easier to heat them up than one big block. again, race tyres are designed to run at a temp and even if 150s ran 125 wets i still doubt they would get upto the correct temp, making the tyre about as useful as at slick.

Who knows because both tyres aren't running at the correct temp, all the grooves could be doing is removing surface area for the tyre to contact the road, and the slick with no groves offereing more surface area could offer more grip.. Who knows..

160 ks is still fast for limited grip

I say keep it as productuon tires

160ks is fast.. but 280 on a superbike with limited grip is even faster.

No matter what tyre you are on, if its wet, there is going to be a reduction in grip levels. Every single tyre has a level of grip regardless of make/design, and every rider needs to know that level and ride past if they want to stay on.

I say keep slicks. Tried and prooven

go away saftey nazis

[Flyno]

Glen, the grooves in a wet, DO ALOT! they push all the water out from under the tire, so in the rain the wet can get a better contact patch, hense better GRIP!

[Bykmad]

The grooves pump water away from the contact patch. Slick tyres do not move any water, they simply run across it, rendering them very likely to aquaplane.. Wets pump a lot of water when new, but as the sharp edge is worn off the grooves, they move less water. Wets are also a softer compound, to allow the rubber to grip better in the cooler conditions generally encountered during rain.
The difficulty faced here by MNZ is that the original rules stated that DOT road approved tyres MUST be used. The rules for street stocks were never changed, but the tyre rule interpretation was allowed to "evolve". Now we have the situation that ALL the South Island "Juniors" are running to a different set of rules to that contained in the MNZ GCR's.
NOW FOR THE CRUNCH!
If a rider is killed, the coroner reviews the Police report on the death. The Coroner looks at the organisation of the race meeting, the safety standards applied and the relevant rules for that racing class. It does not take a Rocket Scientist to realise that if the tyre rules have not been enforced, that someone, somewhere, is in the gun! That someone, is the Steward and the Clerk of the Course. The end result is that one or both of the Steward and Clerk of Course could, Probably will (as they are not Labour Party Caucus members) be charged with manslaughter.
Don't laugh. I spent a number of years working in the Coroner environment and they look at rules being rules, not simply guidelines.
Get together and have the rules moulded into an acceptable template, but also realise that a Coroner in an inquest can ask questions as to why a rule was changed.

BE VERY CAREFUL. We are in a fantastic Sport which has inherent dangers.
Think about the changes you want to make.

[sAsLEX]

The grooves pump water away from the contact patch. Slick tyres do not move any water, they simply run across it, rendering them very likely to aquaplane.. Wets pump a lot of water when new, but as the sharp edge is worn off the grooves, they move less water. Wets are also a softer compound, to allow the rubber to grip better in the cooler conditions generally encountered during rain.
The difficulty faced here by MNZ is that the original rules stated that DOT road approved tyres MUST be used. The rules for street stocks were never changed, but the tyre rule interpretation was allowed to "evolve". Now we have the situation that ALL the South Island "Juniors" are running to a different set of rules to that contained in the MNZ GCR's.
NOW FOR THE CRUNCH!
If a rider is killed, the coroner reviews the Police report on the death. The Coroner looks at the organisation of the race meeting, the safety standards applied and the relevant rules for that racing class. It does not take a Rocket Scientist to realise that if the tyre rules have not been enforced, that someone, somewhere, is in the gun! That someone, is the Steward and the Clerk of the Course. The end result is that one or both of the Steward and Clerk of Course could, Probably will (as they are not Labour Party Caucus members) be charged with manslaughter.
Don't laugh. I spent a number of years working in the Coroner environment and they look at rules being rules, not simply guidelines.
Get together and have the rules moulded into an acceptable template, but also realise that a Coroner in an inquest can ask questions as to why a rule was changed.

BE VERY CAREFUL. We are in a fantastic Sport which has inherent dangers.
Think about the changes you want to make.

So change the rules to how it is currently run. Simple.

[Sketchy_Racer]

Slick tyres do not move any water, they simply run across it, rendering them very likely to aquaplane..

If you can get a street stock 150 tyre to aquaplane, i'll give you $100!!

Considering the actual contact patch of these narrow tyres is about the size of a 50c piece.. im seriously failing to see how it could aquaplane. Even at 160kph.. I just can't see it happening. and from what the last 50 juniors on slicks in the wet have proven, it doesn't happen.

Honestly, if we start making them run DOT approved tyres, a lot of them are only going to able to afford some of the crappiest crap (which still cost 5x the amount of the slicks) We will see 10x more crashes. Even some of the more expensive tyres (conti citys) give the crappest wet grip i have ever ridden

My opinion is based on experience.

I don't know the technical, but i know from experience that i'd be paying a shit load more to be riding on slicks in the wet, rather than A DOT approved tyre like a conti-city.

[oyster]

Before my time, but I believe Tim Gibbes "invented" Streetstock for the very successful "Suzuki series" I have a program here dated 2001. The rules are clear, the tyres must be Dunlop tt900GP. Nothing else allowed.
When the rules went into MNZ rulebook, the tyre rule was dropped. Check yourself, no mention, so in fact tyre rules could easily be interpreted as "open tyres" as per F3,4,5. All of these similarly have no definition.
Yes, we all all know production classes traditionally have road legal tyres, but rules are rules, and tradition has no place here! MNZ left the door open by not carrying through Tim Gibbes rules.
In the South Island we saw that opportunity, but as we went along we took out the ambiguity by getting Supp rules, allowing slicks. At the National meeting that created all the fuss, there was no rule breaking, the Supp rules were in place to be sure. We were advised by MNZ the year before that the tyre rules was at least ambiguous, (even though we had Supp rules that year too) so we were to "tidy them up" which we did.

[oyster]

Sketchy came down for the last National round and we put him on the same bike he recently finished the Vic Series, I think he did a pretty good time, a 1.57, which is around 3 seconds off the lap record (actually set the on the very same bike.) In qualifying a youngster on an RG with grooved slicks went out and did a 2.05 in the RAIN. Not just wet, but RAINING. And I believed him, he said it was "easy". Now equate that to Manfeild, a fair "conversion" of that lap time would be around 1.32 or 1.33. You Vic club guys, has anyone done a time like that around there in the RAIN? Would you really want to try that after you've done about 4 meetings of absolute thrashing (1.26's) of the DOT tyres? No, the treads become absolutely lethal in that situation, that's the basis of our concern that makes us request tyres to be "Open" (but no wets) for Streetstock. Wot you say Sketchy? Do you remember Tom's performance?

[FROSTY:Me]

Oyster--I Think its fair to say that the streetstock tyre issue has come up as a result of the Teratonga round of the nationals.
The MNZ guys were I think "unfortunately" positioned round the track when the 150's raced.
They saw the crashes on the last corner before the back straight in the wet AND they saw the bikes shimmying around on the slippery section of the back straight. I must say from my pits it looked prety scarey.
Is there a tyre available that could be purchased in bulk for SS bikes??
Some sort of custom "cut slick" kinda like the Metzler racetec?

[Sketchy_Racer]

Damn straight i remember Toms performance. And what a performance it was!!

One of the deciding factors that have given me the opinon towards this matter that i have.

I just can't see why people can't look for the proof in the pudding. It's really not that hard to see.

[Sketchy_Racer]

Oyster--I Think its fair to say that the streetstock tyre issue has come up as a result of the Teratonga round of the nationals.
The MNZ guys were I think "unfortunately" positioned round the track when the 150's raced.
They saw the crashes on the last corner before the back straight in the wet AND they saw the bikes shimmying around on the slippery section of the back straight. I must say from my pits it looked prety scarey.
Is there a tyre available that could be purchased in bulk for SS bikes??
Some sort of custom "cut slick" kinda like the Metzler racetec?

I will personally give you $100 if you can get a streetstock to 'aquaplane' (assuming thats what you mean by shimmying around)

Looks are nothing. A superbike looks scary going past a 280 clicks. Ask the riders. Its the riders problem at the end of the day, and of the whole feild is comfortable, and feels safe wheres the problem?

And, the crash record for SS150 i bet would probably be quite a sight better than say F3, or F2.....

[Kickaha]

So how many bikes have crashed in the wet on wets or treaded tyres? I know I've seen a few

best we only race on dry days from now on

[Sketchy_Racer]

Don't joke too much there Kick.... if things keep going this way... ya just never know

[Buddha#81:Me]

So heres a curveball...... young Jimmy on a RG150 on a cheaper dot approved tyres bins it and unfortunatly sustains head injuries....... Jimmys Mum and Dad turn off the life support and the Police and Coroner start their inquiry the Tyre manafacturer is contacted........ "What do you mean, those tyres are high performance street tyres, they were never designed to be on a race track".

Oh maybe we should be racing on race tyres.

[oyster]

Frosty, we investigate EVERY incident / accident in Streetstock. (That we practically can) The Steward came to me after that practice and said there were 3 accidents, supporting the concerns of some riders who'd spoken to him.
I followed up and found:
1) Ran out of fuel
2) Fell off on treaded tyres.
3) Fell off on Slicks. A novice rider (only 5 meetings), on the first lap, got back on and qualified 2nd on pole. I don't think there was a tyre problem here....

Spud. This is not a "curved ball", this is reality. I fixed a flatty for an Invercargill youngster the other day. A virtually new tyre, it ran about 3 mm out of shape and took 100 grams to balance. It was a rear so I let it go. If it were a front, I would put a knife through it. Theses tyres are just glorified commuter tyres. The speed rating for TT 900 is only 180km/hr for 1 hour,
so imagine an endurance race at a fast track like Puke with far greater than road stresses. People confuse these tyres with the ones produced for Sport Production racing which are really race tyres made road legal. Not the other way around.

[Tim 39]

Yea the bit that amuses me is that we can't use slicks in the wet because the manufacturer intended them for dry weather. well the manufacturer intended for these tyres to be ridden to work and back with, not for racing.....so where do they fit in? to be honest it's all political bullshit, I'm not blaming MNZ because it's not their fault that our justice system punishes anyone and everyone