Differnece in Altered Partial Streamline and...

[BiggerDanno]

This may not be the appropriate forum, but since it's my first post, I hope you'll forgive me if not...
 
 What's the difference in Altered Partial Streamline and Modified Partial Streamline as related to motorcycles.
 
 Either I cannot read too well, or they've hidden it in the rules, but I cannot find what the differences are in requirements/restrictions.
 
 Can someone more enlightened than myself (not hard to find) please tell me?
 
 I'm trying to figure out which class my bike would be better suited for and/or built for.
 
 Thanks!!!  
 
  <small>[ July 12, 2004, 05:47 PM: Message edited by: BiggerDanno ]</small>

[Dakin Engineering]

First would be wheelbase, I believe.

[hawkwind]

Hey Danno there is no difference between modified  partial  streamlining and special construction partial streamlining  if you are only looking at "partial streamling " they bothh use the same rule /s
 Gary (hawkwind)

[landracing]

hawkwind,
 
 You can never be so wrong. There are a few big differences you need to be aware of.
 
 Seat position needs to be blow top of rear tire, fuel tank capacity below 1.3 gallons, foot pegs must be near rear axel, wheelbase differences between classes. THere are major design changes for a special construction bike.
 
 Special construction bikes are purpose built bikes for speed, but the rules allow only a 1.3 gallon fuel cell. Now why is that since that machine is sapposed to be faster then a modified machine but carry less fuel.

[Seldom Seen Slim]

Yeah, I was wondering why the tank has to be 1.32 gallons (which, by the way, is 5 liters) OR LESS.  I extrapolate, therefore, that my special construction (a.k.a. "altered") bike (if'n I was to build one) would need to get at least 5 mpg to make a full five-mile pass on the long course, allowing a bit of fuel for warm-up at the line.  Or, if I was to run in gas class and got less than the 5 mpg, I'd have to carry a sealed container of gas to the line, warm up the bike, and have an official watch me top off the tank before I make a run.
 
 Back to the original question, the words "partial streamliner" mean the same in either Modified or Altered -- no change in bodywork -- other than what would be required to get the seat low enough and the pegs back far enough.
 
 Does that help muddy the issue enough for you?

First off, it depends on which organization.... AMA or SCTA.. the rules are different
 
 
 second... there is a big screw up with the SCTA Modified vs. Altered "special construction" rules this year..... The ONLY way to get from Modified to Special Construction is to lengthen the swingarm. The other items... <1.3 gal tank, seat lower than top of year tire... so forth ARE NOT REQUIRED as the rules are written this year, OR they could have just one of the features... but would then need a longer wheelbase to qualify...
 
 I dont have the rules in front of me, but I've read them over and talked to Tom Evans, just to make sure I was reading them correctly... and I was.
 
 I will post them when I get home tonight....
 
 as for AMA, their rules are little more clear. Wheel base and seat height... unless you have a bike that is otherwise legal for Modified, but it has a longer than Modified rules spec. wheel base, then it bumps to Altered "Special Construction".
 
 
 to be honest, both orgs. will need to clean up the rules for next year, and nail down what the "intent" of the rules governing the two classes are, and the "intent" of the exceptions. By that I mean... are they trying to prevent someone from putting a longer swingarm on a otherwise Modified class bike and running it in Special Construction, reserving that class for specially built chasis ONLY?  ... or should you be allowed to do just that... and if you dont go to the trouble to built a special chasis, and not take advantage of all the things you CAN do in that class and can still run as fast, if not faster than someone who did... good on ya?
 
 I've gotten the word from AMA/Bub's that they hold the latter to be true... no word from the SCTA... good luck getting any.

[BiggerDanno]

You are both speaking of "Special Construction", I am asking about "Altered Partial Streamline" as in APS-BG/1350 VS. MPS-BG/1350. Is the "Special Construction" the same as "Modified"?

[Seldom Seen Slim]

Yes, indeedy, there are a number of instances in the rulebook where an English teacher might be able to do some good in cleaning up the phraseology and word choices. "Modified Production Class" doesn't seem to work -- that is, production is "just like the factory made it" and "modified" is "changed from how they made it", I think.  And "streamlining open class" can't really exist, 'cause no streamlining is allowed in open class, which many folk refer to anyway as "naked bike" class.  And somebody might think about defining "special construction" because it sure seems to be the same as when they say "altered".
 
 I'm thinking about volunteering to offer some editing for the next iteration of the rulebook.  Hey, an attorney could have a field day trying to pin down a rulemaker with all the various uses of some of the words in the rules.
 
 See you on the Salt, boys and girls, in about a month!

Frame types:
 
 Production
 Modified
 Special Construction
 Streamliner
 Sidecar
 
 
 now.. there are tons of names for all of these depending on the org.  BUT here is the generally accepted usage.. as defined by the way the classes are displayed in the record books...
 
 P = Production
 M = Modified
 A = Special Construction, Altered, Exclusive Construciton
 S = Streamliner
 SC = Sidecar
 
 
 So... biggerdanno, NO, special construction is not the same as modified.

confusing at best.
 
 BUT, if you look back at my post and use the the last post a key to figuring out which class I am talking about... it should all make sense.. after a few beers.

Then you get into streamlining...
 
 NO Streamlining
 Partial Streamlinig
 Streamliner
 
 now, each org. calls these classes different things... OPEN Motorcycles, Streamlined, Partial Streamlined...
 
 but there are only 3 variation on the streamlinig theme, and they are listed above.
 
 You have to look at the records to figure it all out....
 
 now, StreamlinERS are a frame class AND a Streamlining class, and have requirements unique to both categories and they CANNOT be sperated... i.e. You cant run a Streamliner frame with NO streamlining (bodywork).
 
 However.. you can run a Modified frame class bike in both Open (NO Streamlining) and Partial Streamlining... just by removing the fairing.
 
 
 make it all about as clear as mud?  

The other unique class in regards to frame config and stremalining is Produciton.
 
 its just that... nothing allowed other than the way it came from the factory... with the exception of adding the safety features... safety wire, cut off switch...
 
 but no modifications to frame or streamlining allowed in Production class.

[BiggerDanno]

Yep, clear as mud.
 
 Now, back to my original question, what's the difference in altered vs. modified? (SCTA rules)
 
  <small>[ July 13, 2004, 06:09 PM: Message edited by: BiggerDanno ]</small>

[Dakin Engineering]

68" wheelbase is modified. 68.1" is altered (SC). Seat lower than top of rear tire with bike loaded (SC).
 Less than 5 liter (1.32 gal) (SC). Rear pegs closer than 6 inches to rear axle (SC).
 
 sec 7.F.13

[Dakin Engineering]

Whups! Here's one of those ~inconsistancies~, page 97 (under Modified Frame) says "The handlebar grips and seating postion must not be lower than a horizontal line drawn even with the uppermost portion of the wheel rims."
 
 On page 100 (in bold print)" * Seat lower than top of rear tire with bike loaded." as a disqualification for Modified class.
 
 Gee, I don't want to enter the wrong class. Is the seating height determined by rim height or top of tire?