Hirth F23 exhaust length

[Orv Judd]

I have a Kitfox LITE with a fuel injected F 23.  I am interested in finding out the proper length of the exhaust from engine to exhaust port on the muffler.  Is there any one who can help me with this question. I can not find this info in any of my engine manuals?

[facthunter]

Seems a Pretty Plain system  with No expansion chambers  I don't think length is critical but someone can Measure theirs.  Use thin wall tube for weight saving. 2 into 1 to go underneath, fairly long before it Joins. at small included angle. The cylinders are staggered so expect some vibration, I'd go for an absorbtion Muffler. You might fit a spark arrestor if there's Grass around (Krizmann?) There was plenty of USA ones at one time but in California 2 strokes have been banned.  Nev

[turboplanner]

4 hours ago, Orv Judd said:

I have a Kitfox LITE with a fuel injected F 23.  I am interested in finding out the proper length of the exhaust from engine to exhaust port on the muffler.  Is there any one who can help me with this question. I can not find this info in any of my engine manuals?

You don't have space to fit the Hirth system?

 

If not are you looking at pipes only or pipe and muffler?

[onetrack]

Quote

There was plenty of USA ones at one time but in California 2 strokes have been banned

 

I believe Orv is in Eagle Creek, Oregon, so he just needs to keep out of Californian airspace, and he'll be just fine with his Hirth.

 

Edited November 9, 2025 by onetrack

[facthunter]

It may affect the availability, in the US. Nev

Edited November 9, 2025 by facthunter