Modified M/C Class and streamlining behind and under???

[wolbrink471]

Hello All

Over the last three evenings I have read nearly two years worth of 'topic' searched posts and I think I dare post my first question...or rather a plead for a "garage" definition

What is the difference between the streamlining allowed in the Modified M/C class and in the MPS class.

From the posts I have read and the photos (especially Seldom Seen Slim)...the only streamlining prohibited in the M class is that which is positioned in front of the rider and directs airflow. All of the remaining bodywork must comply with the partial streamling rule 7.G.11

What about belly pans and the flat sides of the bike ahead of the riders legs?

Also at what point does the shape of a required component become streamlining. ie. a shaped gas tank that a rider could 'tuck' behind.....nevermind being able to see where you are going ?!?

This forum is like an after school TV special.......entertaining and INFORMATIONAL!

Thanks
Mark

[Seldom Seen Slim]

A couple of years ago I was running in "naked" bike class -- and the decision was made by the officials that even the coolant overflow tank -- which was in the stock location positioned in front of my left leg -- would constitute streamlining, so I removed it, ran the course, got the record.

My "dashboard" rides at a forward-tilting 45-degree angle and I made sure I questioned the officials before I made runs -- that I WAS allowed to keep as it was.

The latest iteration of the bike has the MoTeC on a shelf out in front -- covered when the bodywork is on, in the breeze when "naked".  I submitted photos of that arrangement before leaving for the Salt -- the computer out there is okay in my case.

Belly pans -- what's the pan attached to?  On my bike it is secured to both front and rear parts of the body, so if no front piece -- no belly pan.  Flat side -- what's the flat thing that's in front of the rider?  If it's perfectly in line with the direction of movement I'd think you might get approval -- but I'd sure as heck submit good photos and keep the reply stapled into your logbook/notebook when you appear in impound.

The rule doesn't want anything in front of the rider that might be construed as plced there to direct airflow.  A gas tank -- maybe.  A gas tank that appears to be constructed to help with aero?  Don't bet on it.

[wolbrink471]

So I suppose I would get the finger for showing up with a two piece 'hinged' radiator?

instead of -- think ^

Hey Seldom Seen Slim....sorry about standing in the middle of this forum with my mouth open, pointing at your bike and yelling something about the rules.....but thanks for the answers

Mark

[JackD]

The  bike wizards at SCTA have determined the stock ignition cover on a Vincent was streamlining and wanted the entrant to remove it.
Thinking it through to a logical conclusion is beyond their abilities it would seem.
You won't see them around here because in spite of their perceived position above it all , they have been caught in not only inconsistent application of their own rules but bald faces lies to some smart racers.
The car field is a lot more user friendly.

[Seldom Seen Slim]

Nah, no offense even thought about from my end.  One reason we try to observe all the rules is so when someone asks a question and uses our (your) vehicle as an example -- if I got away with something once before -- I'd hate to have that ruled illegal now and have my old record revoked.

A clean conscience makes for better sleep at night -- and less stress waiting for the inspectors to finish looking at my vehicle.

Hey, what's a hinged radiator?  Does it fold back out of the air once you're under way?

[wolbrink471]

considering a 'hinged' radiator.....

the engine builder has warned me that I am going to need an over sized radiator

I started picturing two smaller radiators fixed at 45 degrees on either down tube, instead of one big radiator at absolutely 0 degrees in front of both down tubes......

Mark

based on JackD's answer and your coolant tank exerience.....i think i am dreaming about getting this approved.

[JackD]

Records exist in the book today in the unstreamlined classes that have 2 standard radiators with 1 behind the other like a compound cooler.
Stock catch cans and stock ignition covers are a bit of  stretch and foolish if you believe it makes anybody faster.
How about a finned intake inter cooler on a turbo bike or an oil cooler ?
They just don't think it through and that makes the application and writing of the rule subject to their whims and their buddies whines.

[Hans Blom]

So what about, for instance my 60s BSA 650 which from the factory has a plate at teh bottom of the down tubes, which goes up 3 or 4 inches above the bend and extends a few inches under the motor as well. A simple 'gravel pan' to deflect debris form teh front wheel. Can I basically extand this piece under the frame to the back to the rear tire to act as a belly pan as well?  This is M class as well.

[JackD]

You have to ask yourself does it control or direct air in front of the rider ?
Then the reasonable thing to apply is it a stock ignition cover for example to keep moisture out or is it a panel that is designed to direct the air around the motor ?

[wolbrink471]

hey JackD

how 'bout this.....i know that 'forward of' and in the 'front of' are different, but

do you see an arguement for the bsa 650's gravel 'pan' extending up the front of the down tubes to a point level with the top of the foot pegs?

mark

[Dean Los Angeles]

Streamlining is forward of the rider. The rear end is fair game for anything, mindful of the rear axle and wheel rules.
The forward part is where it gets sticky. A fairing is, duh, obvious. Other things can be sneaky, and you run the risk of not getting them past, unless you can show someone else that has already run with it.
Your first line of defense is to grab pictures of bikes that have run in the past. (I have a bunch!)

[Stainless1]

DeanLA
Just because you have proof someone else bent the rules and set a record does not necessarily mean that their friends will allow you to take their record....
WWJS?
If you think there is a clique, you're probably not in it....

[JackD]

The feet would be considered part of the rider and anything forward of that might be considered streamlining if it controls or directs the air.
A finned cooler certainly controls and directs the air so at that point you have to apply some informed judgement the same for all.
It is tough enough to enforce stable rules but pictures for example can demonstrate and record compliance.
With the push of a button they can go out to anyone with a question.
Chasing the moon with previously unannounced rule changes is bad and only made worse if the book still contains many , many entries that are now in violation.

Stainless made a funny that is not only a sad comentary but true.

Ya gotta think it through.
 

[wolbrink471]

you know, technically a rider's hands are always in front & forward of their feet....

how did the feet become the benchmark...why not shoulders / back of torso / ??

how about this....can we project at the frontal area of the rider forward and then 'clean up' any remaining parts of the bike that are sticking into the air?

JackD or Stainless or anybody

Mark
 

[Hans Blom]

In the case of the BSA the pan would start not in front of, or forward of, but under the riders neck area and extend rearwards about to his feet. Unless I put highway pegs on the bike and could get my feet ahead of my head...