MNZ requests ProTwin comments

[GSVR]

CONSTRUCTIVE COMMENTS REQUESTED
Motorcycling New Zealand road-race commissioner Paul Stewart has requested that you send constructive comments with reasons on the following, please forward your comments to MNZ.

http://www.motorcyclingnz.co.nz/news...rticleID=12167


All the interested partys in ProTwin have the opportunity to have a say and put their veiwpoints forward.

Cheers to Paul Stewart.

Theres also comments requested on other stuff...

[johnsv650]

good one paul stewart, i will send my thoughts away and the more people do the better......

[steveyb]

I have made some comments.
Overall I think the concept is sweet as and works well overseas.
I just commented about making the rules, whatever they may be as I am not involved directly in the class other than trying to sort out a protest at NZSBK Rd 1 this year as riders representative, unambiguous so there is no room for interpretation.

e.g. the tyre rule; Either say what tyres are allowed specifically, or say it is open. No ambiguity then.

Cheers

Steve

[GSVR]

F3

So what are peoples thoughts on allowing inline fours to be bored out to 520cc. That gives the twins a 20% dissplacement advantage which is what they get elsewhere in the world apparently.

I also see back in the old days when inline fours where 400cc twins where only allowed to be 500cc max.

[svr]

F3

So what are peoples thoughts on allowing inline fours to be bored out to 520cc. That gives the twins a 20% dissplacement advantage which is what they get elsewhere in the world apparently.

I also see back in the old days when inline fours where 400cc twins where only allowed to be 500cc max.

A couple of points:
1. The F3 championship in 06/07 was won by a 450/4, which was clearly the fastest bike (and would have been this year as well)
2. 650 twins have to have standard intakes, otherwise capacity is limited to 500cc
In my view the F3 formula seems pretty fair at the moment. Its conceivable that any engine option avaible would have a clear advantage given deep enough pockets and some imagination.

[GSVR]

A couple of points:
1. The F3 championship in 06/07 was won by a 450/4, which was clearly the fastest bike (and would have been this year as well)
2. 650 twins have to have standard intakes, otherwise capacity is limited to 500cc
In my view the F3 formula seems pretty fair at the moment. Its conceivable that any engine option avaible would have a clear advantage given deep enough pockets and some imagination.

Of course at the same time SV650s could be allowed to run any intake system they wanted like the 400s already do. Whos to say some aren't already modified in a legal kinda way!

What might happen is some guy might rock on up with a sleeved down or understroked (with slightly longer titanium rods) 2008 600.

[GSVR]

And back onto the ProTwins...

Do you think the idea is for this class is for it to eventually replace F3 like F2 and F1 has been replaced by production classes. Or is it to have a cheap as possible entry level class.

The reason I ask is becuase this will have a huge effect on which way the rules are updated for both F3 and ProTwins.

[koba]

Wouldn't boring 400's to 500+ be expensive with possible reliability issues?
If it is expensive (I dont know thats why I ask) it kinda defeats the purpose if it is done on the grounds of cost...

[Cleve]

What might happen is some guy might rock on up with a sleeved down or understroked (with slightly longer titanium rods) 2008 600.

Gav (HDT) suggested this to me last year and I have always thought it a very clever idea and not sure why some one hasn't tried it (to my knowledge) A 450 cc "R6" with slipper clutch, upgraded suspension etc could be a wicked F3 weapon.

[GSVR]

Take a current 600 with a bore of 67mm and a stroke of 42.5mm.

You would have to go down to a 61 mm bore to achieve a dissplacement of 498cc. Few issues with valves etc maybe but thats not to say it can't be done. To get to 450cc would be an even bigger ask.

BTW I think Gav mentioned the idea to me.

[FROSTY:Me]

Ya can only stretch things so far. A 400 bored to 450 is a frajile enough beast --take another 12.5cc per hole and you got hand grenade city.

[GSVR]

Wouldn't boring 400's to 500+ be expensive with possible reliability issues?
If it is expensive (I dont know thats why I ask) it kinda defeats the purpose if it is done on the grounds of cost...

Ya can only stretch things so far. A 400 bored to 450 is a frajile enough beast --take another 12.5cc per hole and you got hand grenade city.

Obviously the guy thats racing these doesn't think so or he wouldn't have asked MNZ to consider allowing the bigger displacement.

[koba]

Obviously the guy thats racing these doesn't think so or he wouldn't have asked MNZ to consider allowing the bigger displacement.

yeah, guess so aye!

[svr]

Anything is possible if you want (can) spend enough money. The Formula 3 title has always been vulverable to `buying' e.g. arguably the best F3 bike seen in NZ was the Ducati supermono ridden by Rodney O'Conner ('95??). ZXR400 mounted Nathan Spargo was consistently riding around the outside of this thing on his $8k bike in a futile attempt to defend his championship. The only thing really saving the class is an almost tacit agreement not to spend too much money. Purpose-built european `giant' singles racer anyone (50k)??
Aprilia svx 550 bored / stroked to 650cc (ok with standard intake) in pupose-built gp chassis?? or same with 450 svx motor built with an open checkbook (110kg, 90hp).
How far would have to bore out your 20yr old 400 to beat those bikes?

[steveyb]

IMHO we simply must have a Formula racing class of some description.
The main reasons being; it allows people to develop their motorcycle engineering skills and ideas and it allows people to put together bikes that may or may not cost a lot of money in one way or another.

I think that we often lose sight of the fact that motorsport is not only about the riders, the factories or the sponsors, but includes also the engineers, the ideas people and the teams that build and support the machines.

Without the scope to let ideas run free and hands to roam over tools and machinery and lumps of metal then we will all be at the mercy, so to speak, of the major manufacturers and have to ride what they make.

Nathan Spargo, Tony McMurdo, John Britten, Bill Buckley, Terry Fitzgerald, Andy Bolwell, among many others, are all recent and contemporary examples in NZ of the desire to make ones own machine (Many in F3). I even sold my NSR 250, back in the day, to a young fella that installed an Impulse GSX400X engine in that frame with a TURBO on it. And it worked!!!! Not super-well, but I guess he ran out of resources to fully develop it. But the point is that he had an idea, had a go and, at the time, had somewhere to race it!

We have only one international racing class in NZ, (125GP), we have a good production-based class (600 SP), a fairly good production-based Superbike class, an OK beginner class (Streetstock), a new low cost entry class (Pro Twin which seems to work well), where to for those who want to fiddle and fester and let their imaginations wander?

Formula racing at the highest levels must be defended. Remember though that VMCC run under erstwhile Formula 1, 2, 3 rules.

As for the current proposal (high caps for multi cyls), if one is to take that to its logical extension one surely needs to base it on power to weight ratios and maybe power/torque curve comparisons to see where equity in the rules will pan out. 500cc? 520cc? Hell I don't know. But as I recall vaguely, it seemed that for the Kawasaki and the Yamaha that around 480cc was achievable with pretty standard, not too exotic kit? Could be wrong about that.

BUT, cost must NEVER be a part of writing Formula-based rules, that is for the other classes. If cost reduction is a part of your decision process then you should be deciding to be in another class (now that we have the Pro Twin class) so that you can do that, and do it well.

BTW, what about this idea of blanking off one cyl of a current 600 to make a 450 triple? Does that fit the rules? Are there still 4 cyls and hence still 600cc even though one is not working? How would that be ruled I wonder?

Enjoy

Steve