Cobra F1 mufflers

[a.graham52]

Anyone have experience with them? The ones on my bike are rotten inside. Found that out tonight when I went to go pack them. I found a NOS set that fit a 85-89 zx600r and visually they look the same. The seller hasn't gotten back to me with measurements yet. There just slip ons. Also, how's the V&H 4-1? There's ano abused set on ebay right now.

[FJmonkey]

They sounded real good on my '89 before I swapped it for the RPM system. Pat really likes them as they polish up to his "brighter than the heavens" standard.

[Pat Conlon]

That was one of my first mods on my '84, the Cobra F1 slipons. They are the quietest of the Cobra series.
Cobra slipons come in 3 flavors, the quiet F1, the slightly louder F1S, and the loudest F1R's
My only beef with the F1's are the rivets, which hold the can on to the connector pipe. The volume of air pumped thru our FJ's (in the Kookaloo zone) cause the rivets to pop out.

I currently use the larger inner diameter Cobra F1R's which have a band clamp, a much better design.

They are hard to find, a shame they are no longer made.