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Chair tires

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Re: Chair tires

Postby Stephen Szikora » Fri Mar 09, 2012 9:39 am

I just found this interesting option for a chair wheel.

http://www.cokertire.com/480-10-bf-goodrich-blackwall.html

It's section width properly fits within the 125mm limit in the rules as written. I wonder if it is any better than a trailer tire but I do note that it is for classic Mini's so it should be able to handle a side load. Interestingly, it only requires a 3" wide rim. Hmmm ... are there are 10" trailer rims only 3" wide? The early Mini steel wheel was 3.5" wide so it could be used with this tire. Alternatively, a similar tire is available in 12" and trailer rims that size are readily available.

They also sell a 16" tire that only requires a 3" rim. A little wider than the Dunlop R2's but within the section width limit of the existing VRRA rules.

http://www.cokertire.com/450-475-16-firestone-blackwall.html

A skinny bias-ply tire is not confidence inspiring, but that's exactly what the Dunlop R2 is (and when was the last time you raced in snow!)

Coker Tire has several vintage tires that might be interesting. If someone wanted to try radial tires on 15' rims, this would be an option and the section width is within the rules.

http://www.cokertire.com/125r15-michelin-x.html
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Re: Chair tires

Postby chairman » Fri Mar 09, 2012 6:11 pm

problem is there isnt enough outfits around. so we keep the playing field level. if you want a 3 or 4 cylinder go to P3. they have wide tyres and front or rear exit. as far as spoke wheels go lots to choose from. have not seen a 750 twin shred a wheel . not enough power. the only car techno I see is in the rear engine stuff not old kneelers. as far back as 54 first kneelers used teles. although later some experimented with car style suspension. what class is my triumph in, 1952, teles , rigid frame, 18 inch wheels. would be P1. so myself I dont care if its P1 P2 P3 I will line up and race dont care what against. doesnt matter what place I am in I dont give up, go hard or go home, see you on the line
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Re: Chair tires

Postby tintop » Sat Mar 10, 2012 3:01 pm

I had thought this was a civil discussion, in which tire sizes and possible wheel alternatives were the point. Doing a flame job is not the best way in my opinion to encourage increased partcipation, when you are looking to increase grid sizes. That said, I'll be on the grid at Shannonville, and will be racing as hard as anyone, regardless of the position. Just like I have always done, in any form of racing I have been in.

"..if you want a 3 or 4 cylinder go to P3. they have wide tyres and front or rear exit."

If you actually read my post you would note that I was referring to P3, and I do have a suitable Fiddaman rig (in boxes) for that class. My point was that while solo P2 & P3 have multiple classes, the current engine restriction in P2 (to twin), and capacity/cutoff (900/82) in P3, dissuade anyone from using the Triumph/BSA triple, or Honda 4 SOHC in P3, in anything close to their original size. The intent was to point out that simply adding a 750 displacement / treaded tire class to the existing P3 might encourage additional participation.

As for the tires size issue, the VRRA rule refers to 'width on front, rear, and sidecar." In other words, any tire used on a P2 rig may have up to a 5" tread. So contrary to Shephen's interpretation (see Rick's clarification posted earlier), our rules do follow USCRA.
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Re: Chair tires

Postby Stephen Szikora » Sat Mar 10, 2012 10:07 pm

As one of my favourite professors used to say, "reasonable minds can differ ... just not in this case." Brian, read the rule which I will quote below verbatim:

"10f. TIRES: maximum 125mm/5.00 inch section width on front, rear, and sidecar."

SECTION WIDTH not tread width - these are two different measurements. Section width is the maximum width at the sidewall less any raised letters or rub strip. The tread width of any tire is less than (and in the case of bias ply tires, significantly less than) section width. Further, I gave several examples in prior posts where I not only explained this but gave the actual section and tread width measurements of several tire options.

Your "clarifying" e-mail to Rick Yates is not helpful. You don't appear to have explained the issue in detail to him and I suspect that he is not even aware of the difference between section width and tread width. I have sent him a full explanation and we'll see if he returns with a different response.
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Re: Chair tires

Postby paul whittaker » Sun Mar 11, 2012 8:02 am

Your "clarifying" e-mail to Rick Yates is not helpful. You don't appear to have explained the issue in detail to him and I suspect that he is not even aware of the difference between section width and tread width. I have sent him a full explanation and we'll see if he returns with a different response.

I suspect that the frustration in Don's post is partly due to: both Brian and Steve "nit picking" over some thing which up to this point has never been noticed, is highly unlikely to provide any competitive advantage, is not a technical development from a later era, and lastly is being kept on the front burner by two people who have never raced a sidecar to this point. Can we please let it go and if at the end of the season you want to submit rules changes to the tech committee, do it then. Paul.
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Re: Chair tires

Postby Rick Yates » Sun Mar 11, 2012 10:37 am

I've been away on holiday, so this is the first I've heard of this issue.

The current technical committee does not clarify rules. If a member wishes to change the wording in a written rule, a rule change proposal must be submitted. As far as I know, we have interpreted the 5" measurement as contact patch. We will be inspecting the rigs with this criteria unless I'm informed otherwise.

Send all comments to me at Vrra-tech@hotmail.com

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Re: Chair tires

Postby Stephen Szikora » Sun Mar 11, 2012 11:05 am

Paul, I don't think that is a fair comment. The people most likely to read the rules are those looking to join the fun. If people are going to proceed with building rigs, it is reasonable to want to know how they should be built. To that end, getting a clarification is important before making the investment.

Let the building begin.
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Re: Chair tires

Postby tintop » Sun Mar 11, 2012 9:19 pm

To set the record straight, a few facts. First - I have been dealing with rules for over 35 years, starting with being a member of the Race Commitee of the Whitby Kart club. For 20 years I was a member of VARAC, and served two terms on the BoD. During that time I wrote VARAC's Group70 rules set. Those rules have now been adopted by at least 2 US Vintage clubs. So I certainly feel I have a firm understanding of both the spirit, and intent of the rules that govern vintage racing, of any type.

Secondly, I am personally insulted by the insinuation that I was not forthright in my inquiry regarding rule 10f. I contacted the Tech Commitee regarding this in September of last year. My initial question specifically asked if this was a measurement of the bulge, or the tread. I was asked to put this in an email (posted above), and rec'd on 9/29/11 the reply I posted above. This has now been confirmed by Rick in his latest post to this thread. As far as I am concerned that is the end of the matter.

I will submit a 'rule change proposal' for the next AGM, that the wording of 10f be amended to accurately reflect the Tech Commitee's stated application of this rule. In addition, I will propose that the Tech Commitee adopt the standard motorsport practice of using 'Tech Bulletins', as a means of communicating any decision(s) to the membership.

Brian
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Re: Chair tires

Postby scooterboy » Fri Mar 23, 2012 2:08 pm

just a quick question here, are alloy mini rims ok for the chair, couldnt see any rules or reasons against them but just want to be sure before i go get them
cheers
vic
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Re: Chair tires

Postby MGill » Fri Mar 23, 2012 5:47 pm

Yes they are ok. Just be sure mag is not too wide for tire,
and that offset will not have inside of tire rubbing on chair.
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Re: Chair tires

Postby tintop » Fri Mar 23, 2012 6:48 pm

mgill wrote:Yes they are ok. Just be sure mag is not too wide for tire,
and that offset will not have inside of tire rubbing on chair.


+1 on the mag being eligible as a chair wheel. The Mini 10 x 4 mag wheel with standard offset should fit with not problems on a Whittaker/GBR frame.
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Re: Chair tires

Postby paul whittaker » Fri Mar 23, 2012 8:03 pm

Whittaker/GBR frame.
Hey GBF please, (Gilmour Bracket and Flange). Whose bike did you get? Paul.
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Re: Chair tires

Postby tintop » Sat Mar 24, 2012 10:29 am

apologies Paul, fingers engaged, not brain. :roll:
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Re: Chair tires

Postby Paul&Sharon Bowyer » Sat Mar 24, 2012 6:31 pm

I have one ten inch alloy mag wheel on my period one Norton Feddeman (sp) chair that was raced in the 60's so it should be legal. (I had it cracked checked before using it btw.) Check with Rick Yates the Holy Guardian Of Sacred Machine Preparation Eligibility Rules. HGOSMPER for short. No insult intended Rick. Someday (tell me when someday is Paul and Marie) we will resurrect the money pit/track friction modifier. Three cheers for oil pans.
Cheers Paul B, the other Paul that believes in the value of oil pans/v.s. pain,suffering and loss of income.... having been there. Just expressing an informed opinion as a member. I know that exceeded the question parameters scooterboy.


scooterboy wrote:just a quick question here, are alloy mini rims ok for the chair, couldnt see any rules or reasons against them but just want to be sure before i go get them
cheers
vic
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Re: Chair tires

Postby paul whittaker » Sat Mar 24, 2012 6:59 pm

Someday (tell me when someday is Paul and Marie) we will resurrect the money pit/track friction modifier.
If you don't do it this year the odds are 10 to 1 it won't happen, which may be good or bad depending on the outcome. As we age like a bottle of wine, sometimes the stopper gets lose, and the contents modified against our will. I have a wonky knee and tendons from an old injury (So they tell me) which has never bothered me in decades. Should know better after the practice day if it will be a problem. At least we have no more bump starts to worry about. I like you both well, and this is not intended to push you back onto the track, just an opinion. Paul.
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