80 Trailfire & 81 sportfire

[High Top]

Here is the worst one I’ve got. It’s kinda hard to tell in the picture but there are dents on top and bottom side. I ran the one Trailfire last year with this pipe and I thought it ran fine but my experience with these or any two stokes is fairly limited. I’m fine with leaving dents I just don’t know if one this bad is doing any harm to an engine or not??

[snowmoer]

No expert here, but that one I would not use as is. It could affect how it the motor runs. John Deere had a description in one of their manuals on how their tuned pipe works. It uses energy waves to push some of the unburnt fuel back into the motor for a little extra power. Those dents would disrupt that. The one in your other picture should still work. The dent is not that large.

[High Top]

Thanks Dan for the input. I’ll put this pipe aside for this season and use one of the others. A couple of my trailfires I won’t have time to get ready so I’ll rob one to get this machine done.