Kawi2strokes.com Forum

Have you dyno'd long and short Wirges against each other on the same bike/set up John?

I know that short Wirges on my H2 drag bike when it was a mildly ported street motor added 5mph to my terminal over my Denco's, same bike, same set up, same afternoon. Then Gast street pipes added another 5mph more, also the same afternoon.
Short Wirges work, though I haven't tried the long ones but I'd say well worth while to shorten the centre section if you've gone to the effort of cutting them open already.

well...looks like ill chop 3 inches out while I have the saw out..

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downwind of three mile island

i dynoed the "long" Wirges with the plug out (stock cylinders and pods) same top hp as stock pipes with lower torque through the power band. Then dynoed The wirges with the baffle removed, and 4" out of the body to match the length of the Dencos. HP was within .5 hp of the long pipe. I then slipped on a set of Denco's and picked up 10 hp at the rear wheel.

That was enough for me. Other may find different. But it seems a few others have found basically the same results.

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Twist the throttle, tilt the horizon, and have a great time. What triples are all about...........

If you get the saw out, why not replace the first cone with 3 at the same time? Winter's coming eh!
Adjust the belly to get your tuned length. The baffle cone angle looks ok IMO (after knocking out the plate). Make one set work and you can start retrofitting wirges!

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http://kawatriple.com/wtf/

thanks Andrew..ill just hack up the ones I got..not gonna be in the pipe re-fab buisness

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downwind of three mile island

I would give you mine, but I'm still waiting for my street to be repaved. Gonna video the roller smashing them flat......

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Twist the throttle, tilt the horizon, and have a great time. What triples are all about...........

I started out to modify my Wirges pipes about five years ago. By the time I had decided on all the changes, I realized it would be easier to make a set of Dencos from scratch.

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If it surges, that's normal, upshift.

A conservative move for sure! Denco's are proven to work, but it would be a fun project to get a set of wirges to work better.

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http://kawatriple.com/wtf/

LOVE the bike!!! Nothing wrong with using what you have.

Instead of hearing that Wirges don't work, I would be curious to see WHY. What is the engineering/scientific/mathematical reasonings that explain why they are so inefficient at making power versus other period pipes?

Good suggestion. On my H2, the Wirges pipes would start to fall off after about 7,500 RPM, and be an fairly effective RPM limiter by 8,000. When I first tried the Denco design, I was up to 9,000 by the time I checked the tach. The usual disclaimer: all engines are different, I had non-stock porting and carbs, etc..

Years ago I had calculated that I needed to take a couple inches out of the Wirges pipes to work with my porting, so in my case, the biggest problem on paper was that they were too long. That's what got me thinking I'd fix them. But then I figured while I was at it, I'd do a 2-stage diffuser cone instead of the one long one, and adjust the head pipe length. That's about when I decided to build from scratch.

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If it surges, that's normal, upshift.