Hey Mongo...

No

 

Jim, with respect to your comment on the ambiguity of the rules I could not agree more. I have long advocated the rules could be re-formatted to make them easier to read and understand as well as to remove the ambiguities.

Now as far as this thread goes, you seem to be taking the questioning of the RZ350 F-2stroke displacement limit very personal.

Since you raised the issue of ambiguity you might clarify your use of the term “while You’re at it and you're on a roll” are you accusing everyone that opposes your point of view?. It would appear you believe the intent of the OP and all that oppose you in this thread is to remove your RZ from the grid (with the addition of your H bikes expanding this to all your bikes), if so you flatter yourself. The displacement and legality of your bike in any class is 100% within your hands.

I am not sure why you even raise the issue of your H-series bikes in this thread, reed conversions were available in period and no one has ever questioned their legality in WERA vintage.

 

I think this the most relevant post to date. It certainly shows what the original intent of the overbore limits were for. Some guys use them for loose interpretation and show up with an engine punched out to the max for every possible cc allowed, and then leave no room for maintenance bores.

Even Bob's calculations, all of which are valid points, except for one... I'm actually getting tired of the debate, and I don't want to be a part of some agenda that obsoletes some of the current builds out there. I even think the 421 isn't that much of an advantage, my powervalves would even the gap if I was a better rider... well on most tracks.

I think the point is that there is too much open to interpretation, and everyone is entering the fray with different impressions. I just think the 0.060" overbore is a stupid way to limit displacement, when almost every bike in the class is metric. Pistons are available up to 66.50 mm, which is roughly 0.100", not all of which is practically useful. When you'd be lucky to find 25 year old cylinders on 2nd overbore, the rules don't make you want to dump almost a grand in development when you can only punch them out 2 or 3 times.

Give us some room to work with over the current limits, put a practical limit on displacement that is not ambiguous, and do it quick. Winter builds are in process.....

Will someone verbalize the intent of the group and submit a formal request that has a chance of getting approved? I just really don't want to see the 0.060" spec in the rulebook next year..... I could see 375; 396; 400; 450 as all being an improvement to what we have now.

Sent via DROID2 on Verizon Wireless

 

Well...i don't see what the problem is...really.

 

Bob:

Now don't get me wrong here, God Bob, it's Christmas time and so I'm jovial and pleasant (as usual). But I can't find the words you are reading; where exactly do the rules in vintage spell out "maintenance" bores? Are you finding this specific wording in Chapter 9? This is not to say you are wrong here, this is to say I just can't locate "maintenance" bores.

By the way, I find no latitude for any other interpretation in the following sentence, quoted verbatim from the rulebook, page 44, last paragraph under the heading "ENGINE":

"Any machine with a dispalcement (sic) limit following it in the class rules cannot use these overbores, the listed displacement is absolute."

As a matter of curiosity, tell me how you interpret that sentence? You are saying that the model designation, i.e., RG500, RZ500, RZ350, TZ350, etc, is not a 'displacement limit'? So, for example, if an RG500 was actually 950cc, as it was built by Suzuki, WERA would allow it, on the basis of the 'model designation'-RG500- to compete in the class? We would all pretend it was only 500cc or within reason close to 500cc? We would ignore the fact that is was 950cc?

Why do I get the feeling that unless it is otherwise noted, for example "Yamaha SR500 (up to 540cc)", that the model designation is meant to be the limiting displacement?

Now of course I can read that "Cylinders may be bored to a maximum....080....060....040...from the class limit" Maybe you know, then, what is 'the class limit" in Formula 2-Stroke? Isn't this meant to be a reference to the displacement limits of any bike eligible for the class? For example, Formula 500 includes the "Yamaha RD350, RD400 (regardless of year)." That indicates to me that those bikes are not permitted any overboring, 'maintenance' or not. So stock up on OEM cylinders.

 

Charles, did you actually read the class definition at the beginning of the rules?


I specifically used F-500 for the example as it has bikes that fall under the "class limit rule" as well as bikes that have specific displacement limits.

"Pre 1973 2-stroke factory road racers up to 360cc.

Pre 1974 2-stroke production machines up to 500cc. THIS IS THE CLASS LIMIT for the H1 RD's and ALL production based bikes included in F-500

Pre 1974 4-stroke, 4 cylinder up to 500cc. "

This defines that a TR3 is legal up to a maximum of 360cc's BUT all production based bikes OTHER THAN SPECIFICALLY STATED EXCEPTIONS (see Sr500 and GS450) are allowed 500CC's max PLUS overbore.... (I used the term "maintenance bore" it was the term used when the rules were explained to me).

Engine rule based on maximum class limit:
"Cylinders may be bored to a maximum of .080” singles, .060” twins, and .040” three and more cylinders from the class limit."

So for production based 2strokes the following applies, class limit of 500cc's plus standard overbore limits as defined under the "Engine" rule.

For the SR and GS450 the following rule applies:

"Any machine with a dispalcement limit following it in the class rules cannot use these overbores, the listed displacement is absolute."

Displacement limit for the SR/GS as stated under thier inclusion in F-500 SR500s (up to 540cc), GS450 any year up to 550cc.
The TZ350 4 port is specifically named (with the 6 port G cylinder being excluded as is the TZ750 4-port cylinder (373cc's).

:up:

I hope this clears it up for you

 

Formula 2-Stroke

This is a Vintage Formula class where hybrids up to 1985 are permitted. Alloy race frame of the perimeter type may be used as these were available in the period, but twin spar (“Delta Box”) frames are prohibited.

Among the eligible Formula 2-Stroke machines are the following: Honda RS 125 (steel frame only); Kawasaki H2, H2R; Suzuki RG250, and GT750; Yamaha RZ350, RZ500, TZ250, and TZ350. Specialty frames, such as Harris, Nikko-Baker and Spondon, are permitted.

Correct Charles

I'll tell you exactly how I would interpret this section of the Formula 2 Stroke rulebook.

Let me preface that first for those who may not know me, I am firmly against any and all cheating in racing, more so Vintage racing, and even more so WERA Vintage racing. I have been a WERA official for a good while, more then some, much less the others.

As the rules are written I see no displacement limit, what you have is a list of eligible machines, both air & water cooled without regard for displacement.

If I found a RZ350/372 or at 421, or at 500 for that matter, its a legal machine as the rules are written.

In most if not all of the other classes they have displacement limits. That is not how Formula- 2- Stroke is written at present.

 

Bob (The Good Bob): again, I left out some passages from your narration...

For the purposes of this thread, I'm focusing on Formula 2-Stroke...yes, I read the 'class definitions' following the bold-type class description (i.e., Vintage 5, Vintage 4, Formula 500, etc.), which definitions describe the displacement limits for various types of machines. And that's peachy, Bob, but i don't see that same 'class definition' for Formula 2-Stroke. Again, please correct me if I am not seeing what's there in the rules on P. 43.

However, certain Formula 2-Stroke-eligible machines are described in the paragraph under the class heading. By no stretch is it all-inclusive, but it is clear that the machines listed by model name have displacement limits, would you agree or disagree with that? Either they do or they do not.

 

To the best of my knowledge I was the first use aftermarket Banshee cylinders and to suggest this thread is not about that is disingenuous at best. Sean has ruled on the subject and it is a dead issue as far as I'm concerned.

The legality of any bike in any class is subject to the interpetation of the person reading the somewhat vague and sometimes contradictory rules we currently operate under. I mentioned the subject of reed valve Kawi cylinders because I believe you could make an argument they are not an "of the period modification" specifically for the Kawis alone - no other brand. Based on my research the first reed valves for the triples were the Gemco package and I'm not sure whether they were available when the triples were current. If this has the potential to become an issue I would prefer it become one now rather than later. I'm not interested in spending a year or two developing another package and having it ruled illegal again as has happened with the aftermarket cylinders for the RZ.

After my performance last year I hardly think I have any cause to flatter myself.

 

Charles, I believe you are being a bit disingenuous when you pose the question about the mythical engine size of a RG 500. The rule book is not what many of us hope it would be, but it has improved somewhat over the years and with some help it probably will continue to improve. I was taught many years ago not to interpret rules. Read them and heed them. If you have questions go to the authority.

For example, I once envisioned entering an old fashioned TZ 750 cylinder in Formula 500. Capacity is 373cc. It is a reed valve, four transfer port one boost port (like the RDs) cylinder. But water cooled and larger than the permitted TR/TZ 350. I wrote Sean and presented my argument and was given permission to enter the engine in F 500. So far I haven't done so, but that is the way I see to resolve questions. Sean is busy and sometimes he doesn't answer email. Stuff happens. If at first you don't succeed try again, or give up.

An answer for the RZ350 riders: F 2-Stroke is for hybrids up to 1985. In the Component Section it says major components must remain "essentially unaltered (like design)". The cylinders are major parts of a major component. If I had a bike in F 2-Stroke and I felt that another competitor was taking advantage of non-period components I would protest him. I have protested competitors in the past (successfully) and would not hesitate to do so again. Would I prevail? I don't know, but that is one way to find out.
Lyn Garland

 

Jim, your assumption or belief you were the first to use the aftermarket banshee/rz cylinders is incorrect. They were used at least 2 years prior to your use by other racers.

From research I have done I believe Gemco's were available in period, I remember them as well as a version from the UK (I can look it up) There were also several home made conversions that made their way to the track in period. It is not as if reeds were not used in period, look at the RD, it is a period technology and it is a formula class.

This issue for me is that you chose to form this not as a question but as an accusation. If you are genuinely concerned with the legality of your bikes modifications, ask for a ruling yourself, and frame it as a question.

 

Lyn, I think we're trying to settle some things here without protests being necessary...also, remember: "components of later date may used provided the design and operating principles of the component is essentially unaltered." Let's face it: things have changed since the rules were written. And it very well may be a matter of interpretation unless the rules are so clear that there is no doubt at all. Sometimes this is not possible, I understand that.

Charles

 

Charles,

Contrary to Bob W's view point, in the absence of a class displacement limit (as in F-500) or a specified limit for any listed bike I believe each named bike is limited to its standard nominal displacement + allowable overbore.

 

Okay, sure, but first tell me: on what, exactly, do you base your 'belief'?
there has to be something upon which you rest your case-?

 

Wow, it must be winter time.

What do all these posts really mean anyways. This is just the bbs.

I got written clarification from WERA regarding class legality on my hybrid before I built it. Anybody contemplating a significant modification should do the same. Keep the documentation with you at all races and be prepared to show it the race director.

Back to the class at hand, I definitely disagree that aftermarket cylinders shouldn't be allowed. The aftermarket stuff is of like design. You can get OEM bore sizes and stock stroke length porting to match. Yes, the porting is different from OEM but so is a Barlow or Stumm cylinder. The beauty is it becomes a purchase, assemble, and race it deal with little to no development time on figuring the porting out. It once took me a looooong time to get a set of cylinders back from being ported. I've heard other racers complain of the same thing. It sure is nice to whip out the credit card and have a set of raceable cylinders in weeks versus months.

 

Unless otherwise specified by a stated class limit or specific displacement rule (as shown in the F-500 examples) a bikes limit is its nominal stock displacement + overbore.

There is NOTHING in the rules that allow a bike any additional displacement outside the above exceptions!

For the record I agree with Joe, I have no issue with the aftermarket cylinders, it is purely a question of displacement for me.

I am under the opinion that stock 54mm stroke with a 66.5 MAX bore limit is just about perfect for ALL 350 Yamaha's in F-2stroke, this covers TZ' RZ's and TZ350's with 750 cylinders......

 

As Digger pointed out, there is no mention of stroke or displacement limit. So, as long as the bore on an RZ isn't greater than 0.060" over than the stroke is open season for changing.

 

Joe, I believe the rules work as follows: the absence of a stroke limit does not allow you to stroke a motor or ignore the stroke as it relates to displacement. The absence of a class limit or a specific displacement rule for a bike limits the bike to it's STOCK displacement + overbore, any stroke modification that exceeds the stock displacement + overbore limit is illegal.


I said @ 66.5 mm bore @ stock 54mm stroke, it can be stated as displacement, it would equal a limit of: 375.11 CC's BTW this would also cover a stroker crank /stoke bore combination 58mm stroke @ 64mm bore = 373.17 CC's

 

Bob you are welcome to interpet my comments in any way you like. I have no concerns with the legality of my bikes - only with the interpetation of a vague set of rules.