F3 regs

[lostinflyz]

i thought letting 250gp into the scene would be fair enough now, but looking at the top lap times set through the days they would be too quick for f3 with even a half decent rider. for the most part any lap records i can find show 250's as being around 2sec quicker. except at manfield.

in my opinion you cant bin f3 as its the only class where you can be creative. making pro twins the new f3 just makes more and more stock racing, which isn't why alot of us enjoy the race scene as a whole. There seems to be alotta myths and rumors about f3 that turn alotta people off. That being said there are some areas that a small restriction (frames, mag. or cf wheels) now would be a really good idea before more people start going that way to control some costs and encourage more people to step up from club level to nats.

[satchriossi]

You're right, GP250s are alot faster than many people think. We're talking machines weighing a shade over 100kg and making 90+horsepower at the crank (for the final versions anyway). Not a fair match for an SV650 to be fair.

[TonyB]

I think the 300 idea sounds good as you put it satchriossi- doing it to make a cheap competitive 300 based on production parts to keep the costs down. But the problem is that someone with more resources will see it as an opportunity to build a highly tuned 300, and clean up.

[Whitebait]

Imagine that!! http://www.classic-motorbikes.com/st...f=FA97&Lang=en

[scroter]

Hey,

Either that or get the pro-twins opened up to <300cc production based two strokes - that'd be as good really seeing as they classes run together in the Vic club anyway.


Tom

Im not familiar with the bike your talking about but in the 08/09 PMCC series there were 2 RD350's in pro twins.

[quickbuck]

Imagine that!! http://www.classic-motorbikes.com/st...f=FA97&Lang=en

Yup, not bad for a Yammy.
Engine Carter? I'm not totally up with terminology, but is that what we call Crank Cases?

[steve74]

I support the 300cc production 2 stroke idea. I remember when 250 production machines such as the NSR, RGV, KRIS etc were no longer manufactured and sold by nz dealers and the pressure was on for MNZ to introduce new bikes that could win Sunday and sell Monday. In comes the big F3 reshuffle which put standard 250cc production 2 strokes in the same class as 650cc twins and 400cc 4 strokes. But wait..... The 650s were too fast!!!. So to correct things a bit the 400 4 stroke was allowed to run 450cc but the 250 had to remain standard. All well and good that formula 3 is an unlimited budget class with plenty of room for kiwi ingenuity and imagination but why heavily penalize the poor 250 production 2 stroke. My RGV will never be in the same league or budget as the class leading sv650s or zxr450s but it would be good to be given the freedom and opportunity to modify it. If a pre 2000 TZ or RS is doing lap times just off the top F3 guys then how will a mid 90's 300cc production bike hurt?

[Kickaha]

If a pre 2000 TZ or RS is doing lap times just off the top F3 guys

A TZ or RS should smoke any F3 bike and should be giving the 600 boys a hurry up

[steveyb]

My 300 cost less to build than what it would cost to buy an NX5 RS250 in decent condition. It weighs a bit more and makes abit less power. Its motor uses modified NSR150 barrels and heads (so not really an overbore) fitted to the NSR250 crank cases so its all mass production based stuff. As its power comes more from increased displacement, rather than a high state of tune, it doesn't cost as much to run as a full on GP bike either - which was always the aim when i was building it.

So in one breath you so say you want to bring GP 250s in and in another breath you oppose allowing big bore kitted 250 production bikes to run on the grounds that its too expensive... Explain yourself.




I worded it like that to add a little humour. That little sentence REALLY pissed me off. Think about it now, would you have said it to me like that if we'd been face to face? If you carry on with that condescending attitude you'll find plenty of people ARE going to be keen to jump down your throat at the slightest oppurtunity. As I have.

Dude, take a breath!! Geez. Why so defensive?
I put the quote marks around it to make a point. You know, not everything typed here is a one way conversation. The entries are made for others to read also are they not? You didn't start off by writing to me, so why think that I am writing to you, directly? You know, some people do only "have a moan" and expect that to change things, esp people who write to this forum. If you are different, go ahead and make that submission.

I am perfectly capable of being corrected and accepting the validity of what you assert about the 300 kits. I have never investigated it myself other than seeing them for sale via Tyga. I was under the impression that they required modification of existing cylinders, but it would seem not. But I would also suggest that the porting on an NSR150 cylinder is not going to allow the production of the power that a well ported RS125 (or each cyl on a 250) will produce. Afterall it comes from a commuter roadbike, not a racebike. I suggest that the Tyga kit is aimed at roadbike users, not racers wanting to be at the pointy end of a championship not matter what that championship. If you get in there to port it up to optimise it to make a really good race bike engine, then you are starting to spend time and money on expertise, parts and testing. So in the end one would really end up in a very similar position as the guys who have developed their SV650 and 450 bikes to the pointy end.

So I am sure that your 300cc NSR cost less than an NX5, but how about a bike that is competitive in the current F3 class?

If you suggest that the 300 kit is affordable, then I am quite willing to accept that. But then, after assembling the 300 kit what next? Can you get light, high comp pistons, or must you use NSR150 roadbike pistons? I am guessing that Vertx/Wossner/Wiseco will have a good one, but I don't know. Low volume heads? Advanced curve ignition ECU, Ohlins/WP etc suspension, light wider wheels for good tyres, high performance exhaust, 38-39 mm carbs, reed block, case mods...OK we can go on about it.

My point being is that to make a 250 production bike into a serious Formula race bike is indeed possible and they go really well. If you can do 1:15s around Manfeild then you are getting close. 1:16-1:15's is what "standard" (and I use that term a wee bit loosely) 250 Proddy bikes were doing in 1989/90. But to compete in a Formula class will take much more time, effort and money than only buying a Tyga 300 kit (or making up your own). I am sure you know that already though.

I am half in agreeance with Billy in feeling that it would be quite hard to make one really competitive in a Formula class, but I am all for making it allowable for people to try, and we don't really know as no one has had the opportunity to try.

My suggestion about the 250GP bikes has the following points:
Limit the age so that the NXA is ineligible. Limit to ND5/NF5/NX5 as there is not much difference in real terms between a 1993 and a 2000 and almost all parts are retrofittable. 1986-1991 likely to be not really competitive, but at least one good 1992 bike in NZ would be. I stand to be corrected on the TZ, but following the Australian Post-Classic regs seems a fair place to start, but they are a bit complicated.

Finding a 250GP bike for sale in NZ is pretty tough, but there are a few around. But if there was a championship the supply might all of a sudden dry up. But bikes are available ex-Japan for fair prices. Have a look on www.usgpru.net. The prices in the US are not so bad and with the exchange rate it makes it doable. Just have a think about how much sweat, time and money has gone into Fitgeralds, Williams, Eastons, Bolwells bikes and then wonder if you have the resources to compete with that.

Most riders who would actually end up getting one and riding it are unlikely to be the front running riders as they have other fish to fry. They are really becoming an enthusiasts or gentleman racers bike now, not really a serious racers bike. The really serious racers are on bikes they have built themselves or 600/SBK. I do know that a few more Pre-89 post classic GP bikes are being put together in NZ at the moment. One in my garage in fact.

Laptimes in NZ on these bikes (don't look at the last couple of years 250GP top laptimes as they were set on very new model bikes) are not as great as people think they are. They can go fast, yes, but the new F3 bikes are also very fast. I don't believe that 25GP bikes have consistently lapped in the 1:11 bracket at Manfeild (the circuit with which I am most familiar). Our circuits do not allow riders to really get the best out of these bikes except for Pukekohe. HD might be a different story.

Why have a whole cohort of bikes sitting around when they could be being used to good effect?

And finally, I really believe that the 250GP bike is the best stepping stone for young riders wanting to go to 600 and Superbike competition. A season or two spent on a 250GP bike will teach riders alot more about racing than a Pro-Twin bike (not to knock Pro-Twins, it has its place). So if there was a place for them then there would be a market for them and people would not necessarily need to lose a lot of money getting them and having no where to send it when finished with it.

I think that having a 1-2 year trial period would be a good starting point.

Phew, enough explanation? I have been racing 250 Proddy/125GP/250GP to GP/TT and NZSBK race/round winning level since 1990. I think I know at least a little about what I am talking about. Does scratchriossi have the same background? It doesn't matter, as long as he is keen, wants to do something, has a cool bike and gets out racing, that is the main thing.

Onwards and upwards then.

Steve.

[Shaun]

steveb said

"Laptimes in NZ on these bikes (don't look at the last couple of years 250GP top laptimes as they were set on very new model bikes) are not as great as people think they are. They can go fast, yes, but the new F3 bikes are also very fast. I don't believe that 25GP bikes have consistently lapped in the 1:11 bracket at Manfeild (the circuit with which I am most familiar). Our circuits do not allow riders to really get the best out of these bikes except for Pukekohe. HD might be a different story."

Look at the lap times done at Manfield in Probally 1989 0r 1990- 1991 Pan Pacific series by a lot of 250cc riders

I Know I did 1-09 back then and other Kiwi riders also, and Hikita did 1-08 I think?

So these older 250cc bikes you talk about Steve, are still able to race with the fast 600z Not the F3 Scene mate, Not knocking your idea at all, just high lighting, that with a well built 250 on Modern good tyres, the lap times can still be done

[steveyb]

Have to agree with you Shaun, I don't have access to that information.
But I would perhaps suggest that the bike Hikita was riding wasn't exactly the sort of bike most of us would have access to. Can't say for the one you rode.

I guess the point I am making is that I don't feel that riders who are capable of riding those times will ride in this class these days.

If they are capable/were capable they will be retired (e.g. you, Kris, Troy, Briggsey, not me as I could never ride those sorts of times) or in another, perhaps more serious racing class (eg Sketchy, Midge etc).

But in the final washup, if we suggest a 1-2 year trial period and it comes to pass that they are too fast then the market will decide if that is a good thing and everyone rushes out to buy one, or that they want to go back to the status quo wherein only three riders get to win everything and no one else is willing to invest the time, ingenuity, sweat, money to get up with them.

But we must also realise that in motorsport, if you want to win then you must get the best bike you can buy, build, borrow, steal (perhaps not so much of the latter please) and then learn to ride it faster than it will go. How many riders in NZ seriously take that approach? Only a couple of handsful I would suggest. The rest of us want the rules changed to suit our budgets/imaginations/skill levels.

So there is of course the real possibility that someone will search around and buy a 2000 model ex-GP NSR250 or something. Then where would we be. But that is the nature of the beast.

Righto

Steve

[Billy]

The fact is at that Pan Pacific meeting in 91 there were a raft of riders (approx 10) who went well under the 1.12 sec bracket and in fact John Reid was in the high 1.11s on what is now a pre 89 TZ250U,Sure those riders arent around anymore,But what about the likes of Cam Jones,Alistair Hoogenthingy,Avalon Biddle,Tim McArthur,Glen Skachill ??And dont discount the likes of Troy Odonoghue,Kris Shirriffs and Dave Cole making a comeback all have achieved high 1.11s without pushing,In fact Kris managed a 1.12 flat on Ozzys RS having not ridden a roadrace bike for 2 years.While I agree it would be a spectacle too watch all the above riders battling with the top F3 bikes,I have no doubt a 250GP machine ridden in anger by many if not all of the above would be circulating in the low 1.11s high 1.10s and would decimate the class.Thats assuming they could find a 250GP machine to ride

[steveyb]

I think we are closing in on a concensous of sorts.
I think the points Billy makes are good ones about a place for younger riders to go other than into 600SP or Pro-Twin.
It would take them sometime to be able to ride at those speeds.
I disagree about words such as "without pushing". Those laptimes were done in competitive races and those riders like Kris and Troy didn't really just ride around, they always pushed as far as I could tell, and those laptimes weren't done on their first laps back, but after a bit of practice.
But the current F3 lap record at Manfeild is in the 1:11 isn't it? (Ihope that is right).
So I see it as just another category of bike that is capable of running near/at the front and would push the current riders onto more improvements and faster lap times. I am sure the Williams/Fitzgerald/Easton/Ozzy bikes/riders are capable of going faster and faster.

[Billy]

1.12 flat as set by Glen Skachill at last years National round.The point being,It has been shown the 250GP machines can circulate at laptimes far in excess of the current F3 machines.I would have thought the best step up for a younger rider would have been a new 600 converted too an Ozzy 450 for the first step up to allow the rider to become accustomed to riggers of a larger more powerful machine with infinite suspension options and once that is achieved convert it back to a 600,Why would you mess with a 10 year old GP bike or even a Pro twins bike which are no more than a commuter bike that has little in common with a 600 or Superbike??

[Skunk]

Maybe Clubs could allow 250GP's at club meetings under Supp Regs?