Vintage Road Racing Association

My understanding of the term is some thing like "Throttle squirting kids" (the younger set, as we were many moons ago). the 50cc class is just a tad low on HP for a sidecar class, But on a trip to Cuba I had an idea that all those CZ/Jawa 250-350cc sidecars hauling bananas etc would make a great starter class, and the riders were likely very competent. Our problem presently is that the overall numbers need improvement, adding another class would be silly. We have no P1 currently running in sidecar and only one P3, in spite of which we had grids of 4-5? for all but Mosport when the USCRA teams saved our bacon. Things should be different for 2011 with Ian back, a new team or two out and threats of other new rigs. 2010 was certainly a low point for Marie and I. As the song says "tomorrow will be better". Paul.

commando wrote:How about adding a new class of side car "50cc side car" we could call it "monkey bike mayhem"...think of the hilarity, a bunch of us fat old farts wringing the necks of some honda z50 minibikes with sidecars

If you go to YouTube you can find people racing the pocket bike sidecars. Two adults on a tiny rig and platform that one person can carry under their arm. Can't say I have raced them but I have (stolen) driven one all day at an event for a toy pit bike. In doing so I also drove around the paddock at 15 - 20 mph with a real sidecar passenger, you really need one once you get rolling.

I love how the 1st place guy gets there with a little leg action....and the Kid America paintjob is also an amusing bonus
http://www.youtube.com/watch?v=idzPxslH8zs
^this is just GREAT!

OK, lets see if we can liven things up a bit We will be having our meeting of the rules committee soon and have submitted proposals for consideration. Since 2007 when we tried to get the AM-CAN going again (as opposed to CAN-AM which is cars) I have been trying to get our sidecar rules back in agreement with yours. Problem is it's not all that clear what your rules say. In your rulebook it says "5% overbore allowed" for P1 and "5% engine cylinder overbore allowed" for P2. I would take both of those to mean 1.05 times the stock bore size, but says nothing about stroke which is needed to calculate displacement. For a different class on page 10 I see "The maximum allowable cylinder overbore is 5% above the class displacement limit." And on page 12 "The maximum
allowable cylinder overbore (except for Open GP) is 5% above the class limit." Again no mention of stroke, but the class limit is displacement, not bore size.

So the question here is, what exactly does "5% engine cylinder overbore allowed" mean? Also does the same limit apply to the Yamaha where it is already being allowed to use a 750 kit to enlarge it from 650?

Thanks, Bruce Richmond #66 USCRA

PS

Made it to Mosport this year and hope to again next year. Would like to do at least one more VRRA event. Any thoughts on Mid-Ohio for the Am-Can? It's a long haul for us in New England but a few make it most every year.

regarding the tech specs for over bore, as Stephen Hawkins would say "you lost me there", I leave it to the bean counters.
Mid Ohio is a great track and handy but, the club that runs the show now is not one of our current three vintage clubs?. It would seem to me strange to host an inter club event outside the group? Are there any sidecars in that club?
Barber is oft touted as another grand venue but is way too distant to be fair to those who cannot get the required time off, or cover the expense.
My gut feeling is that each club should pick an event to host the extra race, or designate the event as AM-Can if there is only the one race. As the events become more crowded (think Mosport, Mid Ohio) it get harder to insert a second race, so it may be that if the series was reintroduced that it might be easier to do at a non premier event? Paul.

[So the question here is, what exactly does "5% engine cylinder overbore allowed" mean? Also does the same limit apply to the Yamaha where it is already being allowed to use a 750 kit to enlarge it from 650?

Thanks, Bruce Richmond #66 USCRA

Hi Bruce, An example is if the class is 500cc it means you can go to 525cc maximum. The intent was to allow reboring to repair cylinder wear.
Paul Bowyer

Paul and Sharon Bowyer wrote:[So the question here is, what exactly does "5% engine cylinder overbore allowed" mean? Also does the same limit apply to the Yamaha where it is already being allowed to use a 750 kit to enlarge it from 650?

Thanks, Bruce Richmond #66 USCRA

Hi Bruce, An example is if the class is 500cc it means you can go to 525cc maximum. The intent was to allow reboring to repair cylinder wear.
Paul Bowyer

Then why do the rules say "overbore" instead of "displacement" ?

cha0s#242 wrote:

Paul and Sharon Bowyer wrote:[So the question here is, what exactly does "5% engine cylinder overbore allowed" mean? Also does the same limit apply to the Yamaha where it is already being allowed to use a 750 kit to enlarge it from 650?

Thanks, Bruce Richmond #66 USCRA

Hi Bruce, An example is if the class is 500cc it means you can go to 525cc maximum. The intent was to allow reboring to repair cylinder wear.
Paul Bowyer

Then why do the rules say "overbore" instead of "displacement" ?

That is the trouble with printing rules without the underlying intents with the rules. The rules themselves often do not state the all important 'why'. (something Rick could work on?) This rule was only intended to allow boring oversize to repair worn cylinders. Hence overbore. I cannot find my old rules but I would bet you a nickle that it did say displacment.
Cheers,
Paul

The way the "overbore" allowance is written in the various places in our rules has been recognized as a problem. I did publish a revised version in the Dec 09/Jan 10 Baffled Muffler tech report and stated that the wording would be changed when next the rules were revised.
Unfortunately the 2009 rule changes have taken a while to be voted on, but now they have I assume the rules can be updated to incorporate the revised wording for the overbore allowance at this time. I will send these "clarifications" (that word again!) to Rick to be incorporated into the rules.
The wording that we proposed for the overbore allowance is "Cylinders may be overbored to give a displacement of 5% over the class limit" As Paul B says, this was originally introduced to allow a longer life for cylinders by allowing reboring over the class limit, not as a means of overboring cylinders to the maximum size allowable as a means of performance gain, but the end result is the same.
So if the class limit for chairs is 750, then they can be bored to 787.5cc in the same way that CB450s, running in P1-500, can be overbored to 525cc, not 5% over their original bore size.
Clear as mud, eh?
Stan

Stan Nicholson wrote:"Cylinders may be overbored to give a displacement of 5% over the class limit"

Again, this does not cover all angles because it does not adress the stroke. Are we allowed to modify stroke or not ? If it's not forbidded, than it's allowed, right ?

It does seem obvious if not spelled out, that punching the jug and stroking the crank would in most cases grossly exceed the limit "intended" in the rules. If the intent of the racer/builder is to exceed the intent of the rules, they will do so regardless, and who the hell will know in any case. Is there a pot of gold at the finish line? Paul.

Where "displacement" is specified it does tie the bore and stroke together. If you increase the stroke you can't bore so much without exceeding the displacement limit. Stroker cranks are harder to come by then bigger pistons, so I don't think we will see any strokers. Could add "Stock stroke required" to eliminate all doubt. Only problem I see with "Cylinders may be overbored to give a displacement of 5% over the class limit" is that the "class" doesn't have a single limit. Possibly "specified limit" and the example of 750=787.5 would work. Anyway, it seems the Yamaha is to be treated like any other 750.

Please post it here if you come up with different wording. Our meeting of the rules committee is mid January. It would be nice if we could agree on the same wording and that the wording removed all doubt from what is meant.

As far as the cheating is concerned, I think there are many out there that want to take advantage of the rules without breaking them. 5% more power on that long uphill straight at Mosport would be great, especially if it is just enough to keep you even with the guy that used to pull away from you there.

Bruce Richmond USCRA #66

While Bob Coy and Paul Whittaker(who"s son Al raced with me) make some good points about class equilibrium ,I respectfully say you are killing the shade tree guy aka Rudi Kurth,Jock Taylor,the Renick Konig etc ,, C'mon guys you didn't invent the sidecar,,,,s This shit was and is excitibg,,,the 70's were a period of amazing guys and innovators ,,,someday it won't be all overbored 650 twins Btw I'm retired and as such have no vested interest in this class,,tho I do have some period 3 trophy's for a class that no longer seems to exist,I'll send anybody a picture of Rudi Kurth"s machine from 1974 if they will post it...Respectably Gord

Hi Gord, P3 does exist in VRRA and I assume would be allowed to run with SRA? should they turn up. However people writing the rules cannot make racers built/buy bikes, get them to the track. In the years since VRRA's P3 rules were written by a member/s? of the SRA, only one P3 had been out up until this year when Clark was joined by Pierre on a Rotax powered rig, for one race. Clark and the GT750 has been to several events over those years. The old adage of use it or loose it is still true today and that was the start of this thread.
By the way what makes you retired? I consider a racer retired when they are in a box. Paul.