Author Topic: Vintage Motorcycle Class  (Read 5196 times)

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Offline DanMay1776

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Vintage Motorcycle Class
« on: August 29, 2009, 09:19:39 PM »
Excuse me if this has been asked before, but I did search the forums and could
not find an answer.

I am trying to determine all the various classes available for a Vintage
Production Motorcycle. If I assume a production frame, and a production motor,
I believe I would run in:

P-PV = Production Frame, Production Engine, Pushrod, Vintage

Questions:
1. When would the pushrod classification not apply ? A sidevalve/flathead or an
overhead cam engine ?

2. What class would I run in if I had a modified pushrod vintage engine in a
production vintage frame ? Would this be:

P-GV = Production Frame, Gas, Pushrod, Vintage

Thanks,

/Daniel


Offline 1212FBGS

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Re: Vintage Motorcycle Class
« Reply #1 on: August 29, 2009, 09:49:06 PM »
its easier to answer if ya dont talk in riddles..... what cha wanna do? what chassis? what motor?
kent

Offline willieworld

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Re: Vintage Motorcycle Class
« Reply #2 on: August 29, 2009, 10:18:55 PM »
p-pv is  production frame -production motor vintage----------must be 55 or older to be in vintage----in p-pv there is no fuel or blown classes----if you run a flathead you can discount 33 1/3 of your displacement----if the moter is modefied externally you would move up to modefied     willie buchta   
willie-dpombatmir-buchta

Offline DanMay1776

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Re: Vintage Motorcycle Class
« Reply #3 on: August 30, 2009, 08:36:46 AM »
Thanks for the information.

I did not think I was talking in riddles, but let me try again.

What class would a production vintage bike with a modified vintage engine be in ?

/Daniel

Offline k.h.

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Re: Vintage Motorcycle Class
« Reply #4 on: August 30, 2009, 11:15:50 AM »
4-valve heads not allowed in vintage pushrod, unless they were OEM.
« Last Edit: August 30, 2009, 11:17:39 AM by k.h. »
In theory, there is no difference between theory and practice.  But in practice, there is.--Jan L. A. Van de Snepscheut

Offline Stan Back

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Re: Vintage Motorcycle Class
« Reply #5 on: August 30, 2009, 01:20:19 PM »
I think Kent was just trying to get you to be more specifiic.  What motor, what frame, what modifications?

Stan
Past (Only) Member of the San Berdoo Roadsters -- "California's Most-Exclusive Roadster Club" -- 19 Years of Bonneville and/or El Mirage Street Roadster Records

Offline DanMay1776

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Re: Vintage Motorcycle Class
« Reply #6 on: August 30, 2009, 01:57:57 PM »
I am clear on the first class I want to run, as there is another similar bike that ran this year.  I have a 1954 BMW R25/3.  I understand this qualifies for the P-PV 250cc class.  The bike is 100% stock, and this model is pushrod valve operated.  I understand that I can do whatever I want to the internals of the engine, as long as the displacement remains under 250cc.  That means stock head, cylinder, etc.  Visually it must appear stock from the outside, but I can port, polish, tune, and cam it all I want.

I want to know what class I would run if the above bike had a "modified" engine, basically the same stock engine I described, except for non-stock carburator.

Thanks,
Daniel

Offline willieworld

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Re: Vintage Motorcycle Class
« Reply #7 on: August 30, 2009, 02:18:03 PM »
if you modify the outside of the motor (carb exhaust ect) or the frame beyond production you would move to the modified class  in production = p-pv      modefied= m-vg or m-vf  willie buchta
willie-dpombatmir-buchta

Offline 1212FBGS

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Re: Vintage Motorcycle Class
« Reply #8 on: August 30, 2009, 04:25:08 PM »
I'm pretty sure the BMW's don't qualify for the pushrod class..... yes replacing the carb with a different brand would put you into "M" class with out any chassis modifications modify the chassis and it may fit into "A"..... you can do whatever you want to the stock carb!
Kent

Offline Crosley

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Re: Vintage Motorcycle Class
« Reply #9 on: August 30, 2009, 05:20:30 PM »
Don't these BMW's use push rods?   :?
Tony in AZ...

"If you find yourself in a ditch.... let up on the throttle"

Offline k.h.

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Re: Vintage Motorcycle Class
« Reply #10 on: August 30, 2009, 06:39:39 PM »
Airheads count, oilheads don't.
In theory, there is no difference between theory and practice.  But in practice, there is.--Jan L. A. Van de Snepscheut

Offline DanMay1776

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Re: Vintage Motorcycle Class
« Reply #11 on: August 31, 2009, 10:33:10 AM »
Yes, the Airhead BMW's are pushrod actuated.  After speaking with Todd Dross over on the ECTA forum, he clarified what I was looking for:

"Vintage class does not differentiate between valve actuation types, (with the exception of the flathead/sidevalve rule allowing a displacement class reduction which in this case does not relate to your entry)."

Assuming I want to stay in the vintage category, there are only 3 options:

P/PV-(cc)         
M/VG-(cc)
M/VF-(cc)

Does this apply to SCTA rules as well ?

/Daniel

Offline 1212FBGS

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Re: Vintage Motorcycle Class
« Reply #12 on: August 31, 2009, 06:53:36 PM »
correct
kent