2-strokes

[Stephen Szikora]

If anyone has any pictures of creative ways to route 2-stroke expansion chambers on a classic rig, please post them or provide a link. I'm curious to know how the smokers hide their pipes.

A little 2-stroke teaser but no view of the pipes:
http://www.ozebook.com/compendium/suzi/sidecar.htm

[tintop]

I remember seeing a picture in the George O'Dell book of his Windle with a TZ750. Seems to me two pipes came out on the left (like a modern F2), and the other two came out under the driver's right leg. If I can find the picture I'll post it.

[tintop]

I'll have to revise that last post. A picture of the Dave Molyneux recreation of the O'Dell Windle. Give the bulge on the right, and front exit, looks like they all exit on the right.

http://www.flickr.com/photos/patrickdow ... otostream/

[paul whittaker]

Clark Wallace did a beautiful job of mingling 3 expansion chambers together on his GT750. I do not have a pic. I believe John and Art Dailey ran a GT on the Island I bet they have a few pics also. Paul.

[tintop]

Found this video Stephen, of O'Dell Seymaz. Also a TZ750 -

http://www.youtube.com/watch?v=eDbtpZSB30E

[Stephen Szikora]

Thanks, but TZ750's are exactly vintage by our rules. Still, it looks like mounting them on the opposite side from the chair and stacked is one way to go. I did find a video of a T500 rig but it appeared to be running stock pipes which were narrow enough to run very low on each side. Expansion chambers, particularly ones built for torque (wider and longer) will be more of a challenge to install. Ideally, it would be possible to turn the cylinders around and use a rear exit under the rear fender. I guess an alternative might be to run one on each side below the kneeler trays but above the level of the chair deck. I'm not sure that's possible, though because you'd have box them in with sheet metal so no one get's burned and they would likely interfere with foot controls. Maybe another option is a 2-into-1 pipe. They are a compromise but they do exist. I've even seen a GT750 3-into-1 pipe.

Scroll down this link to see a couple of 2-into-1 pipes for RZ350's:
http://www.advrider.com/forums/showthread.php?t=758526

[Stephen Szikora]

Both the VRRA and USCRA rules restrict the modifications to the T500. I suspect this rule was there from the beginning to keep the 650's competitive. Yet, as I understand it, over time big bore kits have been allowed so that the 4-strokes are punched out to 750cc (even, I was surprised in my most recent reading, in the USCRA rules.) I was watching a good video taken by a USCRA competitor from his rig at Mosport. He complained that every time he got to the straights the 750's walked away. Clearly, the big bore kits make a significant difference (as was apparent in the video.)

So back to the T500. Is the restriction still justified? Was it ever? It seems all the rules did was improperly take a competitive period racer and make it uncompetitive. First, one hand was tied behind the back and second, the other fighter took off his gloves!

[chairman]

would a 500 Suzuki be competitive, maybe . it was at one time 650 overhead cam and 750 push rod twin now its 750 across the board and who knows what for BMW . p1 is a good class but seems big inch is what its all about. anyone have a picture of a 650 yam outfit in the period 69- 70

[Percy W]

I couldn't get the picture to load so i put it at this link.
Is this what you were looking for?

http://holdenracing.webstarts.com/gallery.html

[chairman]

nice pics Miles. the black and white is interesting. still looking for a pic of a 650 yam rig taken in the period of 69 to 70

[Stephen Szikora]

Found what I was looking for ... this one is a TR500 but the pipe arrangement would be the same for a T500.

http://www.flickr.com/photos/teamheronsuzuki/1515860749/in/set-72157602317108922/

Alternatively, the following shows 2 of the 3 pipes for a GT750. A cleaner arrangement but only possible if the bike is tuned with short enough pipes. I would think it better to tune for a wider band which usually means longer pipes.

http://www.flickr.com/photos/teamheronsuzuki/1392850436/in/set-72157602317108922/

[Paul&Sharon Bowyer]

Stephen, Are you going over to the Dark Side....??
You are correct about the T500 not being allowed mods when introduced. At the time the worry was that they would dominate the 650 machines. A TR500 engine likely would have.
I remember seeing a two stroke machine with the pipes exiting stacked across the front of the chair and curving back slightly. Cannot remember where though. Must have been hell for the passenger. Hot, stinky and loud.
Paul