Author Topic: Rear Tail Section Length Rule  (Read 14091 times)

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landracing

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Rear Tail Section Length Rule
« on: October 25, 2004, 05:43:00 PM »
I also would like to see the rear tail section be allowed to go past the edge of rear tire. Also should include not having the rule of no streamlining beyond the verticle line thru the rear axel and top of the rim.
 
 Jonathan

Offline Seldom Seen Slim

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Re: Rear Tail Section Length Rule
« Reply #1 on: October 25, 2004, 06:03:00 PM »
Yup, extending the tail past the edge of the back tire would be good -- even if I didn't put a "pointy" tail on the bike, it would sure be nice to NOT have to stress about the body ending first.  On my bike it's REAL close when I've got a smaller tire/bigger sprocket combination fitted.
 
 Are these potential or proposed rule changes, or is this just a "wishin'" list?
Jon E. Wennerberg
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Offline bbb

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Re: Rear Tail Section Length Rule
« Reply #2 on: October 25, 2004, 06:22:00 PM »
I agree. No one has been able to give a solid answer as to why the tire must extend beyond the back of the tail section. The possibilities are pretty interesting once you consider ride height, side panels and tail section height.

Offline Vincent Hill

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Re: Rear Tail Section Length Rule
« Reply #3 on: October 25, 2004, 06:42:00 PM »
I think ECTA allows Plus 3 inches which allow some change in tire size and location. Somewhere here should be the rule
"Made History at Daytona" and still one fast Old Man!

Offline joea

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Re: Rear Tail Section Length Rule
« Reply #4 on: October 25, 2004, 07:28:00 PM »
I would like to see unlimited
 rear length rule with no limitation
 on wheel coverage
 
 second choice
 4 ft beyond rear tire
 
 3 choice 3 ft beyond rear tire
 
 4 choice 2 ft beyond rear tire
 
 Joe  :)

Dave H.

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Re: Rear Tail Section Length Rule
« Reply #5 on: October 26, 2004, 12:09:00 AM »
Curious as to the thinking behind the current SCTA
 bodywork rules. Could they be to reduce the area a
 crosswind would act upon?
 
 I'm not sure I'd want a long tail (lever) sticking
 out several feet from the contact patch of the rear
 tire. Seems like a crosswind gust could get you in
 trouble in a hurry. 2 or 3 feet beyond the rear tire
 seems reasonable.
 
 Cheers,
 
 Dave, the amateur aerodynamacist  :)

landracing

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Re: Rear Tail Section Length Rule
« Reply #6 on: October 26, 2004, 12:52:00 AM »
Dave,
 
 You may be right, but to run on current FIM and AMA rules vehicle may not run for records in any winds on course higher then 3 mph.
 Some may not want that you are correct Dave, but we still want the ability to try it out and allow the innovation of the past let us if we wanted to.. Thats all.  If there is no advantage to it, then you dont run it, but if a guy wants to the rules will be there to let him.
 
 Jonathan

Offline Freud

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Re: Rear Tail Section Length Rule
« Reply #7 on: October 26, 2004, 01:23:00 AM »
When Can-Am ran their 125cc 137 mph, the fairing they used was evolved from a long series of wind tunnel tests. ( Go back thru your CYCLE MAGAZINE library and read the most expensive story the magazine ever bought, that told of the design process for their fairing. It was even more expensive than the story of the motorcycles, helicopter, Kenny Roberts and Cook Neilsen on Maui.) They decided that the amount gained from the extended length was not worth the possibility of the side forces if the wind in the middle of the course was in excess of that at the starting line. They had a long tailed fairing and a short fairing and they chose to use the short one. Review the Kamm effect. The 3 mph wind rule doesn't protect you from Mother Nature.
 
 Don't wish for something that might come true.
Since '63

landracing

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Re: Rear Tail Section Length Rule
« Reply #8 on: October 26, 2004, 01:29:00 AM »
freud,
 
 Doesnt protect a streamliner either... but they still run.
 
 Jon

Offline Freud

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Re: Rear Tail Section Length Rule
« Reply #9 on: October 26, 2004, 01:33:00 AM »
Relate the wheel base of a streamliner to a sit up bike. The tail section is much less in proportion than that of a typical motorcycle.
Since '63

landracing

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Re: Rear Tail Section Length Rule
« Reply #10 on: October 26, 2004, 01:36:00 AM »
Would like to see that article, can you scan and send to me Freud. But I still want unlimited rule on length. Let me be the idiot that learns the hard way. Or let me be the one who goes the fastest.
 
 Jon

Offline hawkwind

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Re: Rear Tail Section Length Rule
« Reply #11 on: October 26, 2004, 04:36:00 AM »
Quote
Originally posted by joea:
 [QB] I would like to see unlimited
 rear length rule with no limitation
 on wheel coverage
 Joe  :)  
 
 
 Joe I have been successful with my rule changes for the DLRA and we will be able to boat tail at the rear and dustbin at the front from 2006 on   :D  
 Gary (hawkwind racing)
slower than most

Offline joea

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Re: Rear Tail Section Length Rule
« Reply #12 on: October 26, 2004, 12:54:00 PM »
I have the can am article.........
 
 my vote it for innovation,
 not limitation.......
 
 if I did everything  was told I
 should do, I ..........well
 we wont go there completely.....
 but I have no regrets
 
 Joe  :)

Offline joea

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Re: Rear Tail Section Length Rule
« Reply #13 on: October 27, 2004, 01:29:00 PM »
streamliners dont have 10 ft high
 tail fins, or tails 20 ft behind the rear
 tire, and guess what, they dont have rules
 specifically forbidding them from doing so either.................
 
 lets be allowed to innovate........
 
 Joe  :)

Dave H.

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Re: Rear Tail Section Length Rule
« Reply #14 on: October 28, 2004, 12:10:00 AM »
Jon, I'm with you. I'd love to see what a modern
 version of the Bert Munro Indian 'liner could do.
 Maybe an Unlimited class for sit-on bikes?
 
 Cheers,
 
 Dave