2-stroke baffle question

[Frank06]

I know that Production class exhaust systems have to be stock looking with outlet size preserved.  With a typical 2-stroke factory exhaust the baffle slips inside a tube in the muffler; baffle removal only changes the outlet diameter a very small amount and it's usually hard to tell if it's there or not (other than sound level.)  Has there been a determination as to the legality of baffle removal for 2-stroke Production class?

thanks,
Frank

[Seldom Seen Slim]

Frank, unmodified means just that.  If you change it "a very small amount" you're violating the intent of the rule.  You might get away with it -- but you might also get protested by someone with a sharp eye.  In production you must produce manufacturer literature and other technical information that will allow both inspectors and other racers to determine if your bike meets the rules.  ECTA relies heavily on the integrity of each and every racer to follow the rules.

[salt27]

Frank,
Cut a short piece off of the end of the baffle and use that instead of the whole baffle.

Don

[Frank06]

Thanks for the information.  In modern pipes (if properly designed) a baffle doesn't necessarily hurt performance.  I'm not sure it's the same story in a 40 year old design!  I'm just gathering as much information as I can before I start my project.

[Bob Wanner]

Worthy Volunteer Frank06 ! (and Son) ,
What kinda two stroke powered machinery you doing ? Inquiring minds need to know.
Bob W ,(still has a ringdingy Lakester, hope to resurrect it this coming LTA/10)

[Frank06]

Hi Bob,

I've got a bunch of 2-strokes in the garage but the one I'm thinking of racing is a Suzuki T500 (Titan.)  I'd still hope to volunteer but would be looking for a way to get down the track just to try it out.

You've got a ring-dingy Lakester?  Details?

[Bob Wanner]

A SCCA formula 500, originally w/ Kawasaki twin and sno mo auto drivetrain, made 72 hp. I replaced the motor with another two stroke rotax triple , came off a sno mo racer, makes 130 hp dyno. Never solved the black magic involved in bringing all that CVT and expansion chamber stuff together, my A.D.D. directed me into the G/BGT Insight I have now, and the LTA kind of temporasrily squashed both racers. Here's a shot of the Lakester at Maxton some years ago.
Bob W

[Bob Wanner]

Ooops, fergot the pic...
http://www.ecta-lsr.com/Gallery/displayimage.php?album=topn&cat=9&pos=0

Terrorized the troops in NC, "Danged weed whacker " !!!

[Frank06]

"Danged weed whacker " !!!

Heh, heh, heh...  Great for discouraging mosquitos!  You were doing them a favor and they didn't know it! 

Sweet looking car BTW.  A lot of the snow machine motors have fantastic specific output.  My other thought was to race a modified H1 or H2 but I'll save that thought for another day.

[Bob Wanner]

I got passed by a Kawi triple a million years ago when they first came out. I rode a 305 Honda "Scrambler", and the noise that ringding thing made was ungodly for those times.
That engine is on my if I had Jay Leno's money project list.
The followers of that H series are a cult, have a few websites out there .
My K/GL was/is louder, not standbehindable. As in pain.
Bob W

[Frank06]

My problem with bikes is that I buy more than I sell....   

I've had my H2 about 15 years and ride it all the time.  It's modded a bit and goes like stink.  The H1 is stock and newer (to me) and it's just a sweet little machine.  I know about and spend more time on the triple forums than I should...

[Bob Wanner]

off topic, but enjoy. First bike is your triple two-stroke based

http://thekneeslider.com/archives/2009/04/24/xj500t-jaybuilt-kawasaki-500-bellytank-triple/
 
I hope some of these guys show up at LTA/2010....especially the 1400cc one lunger
 
BW

[Seldom Seen Slim]

Yeah,, good thinking -- re-gearing so there's more acceleration and less top end.  I can see it now -- the revs increase to where the motor comes on the pipe -- and suddenly the bike wheelies over backwards and the rider is on his butt with zero time to think about how he got there.

[Cajun Kid]

Been there done that,, have the scars to prove it !!


My Old 1972 Kawasaki MachIV  H2 750  was a handfull,, My H1 500 and the My Susuki 1974 GT550  easy as pie.

But the H2  made you pay attention.

Charles

[wobblywalrus]

Be careful about running the standard pistons on the Suzook Titan.  My friends ran one of these as a production racer in the early 1970's.  At high rpm the tops broke off of the pistons.  As I remember, it was 7,000 or 7,500 rpm.  They always ran with racing pistons after blowing up a couple of motors.  The bike ran good, other than that problem.