Tarp grommets are my solution. Got the kit from wal-mart, $4 if I recall. I wanted to put them in a place that is not likely to slide on blacktop to preserve the material integrity.
I put a couple behind the knees a few in the crotch to cool my tool and 2 exhaust ports inside the pockets which are actually covered by the pocket when standing.
I may put one or two on the inside of the knee, in from the kneepad for a ram air effect, but I would prefer to leave that area undisturbed.
I considered just tearing out the liner but then would have to figure out a way to mount the knee and hip pads, plus the liner may provide a couple more feet of sliding time before I'm down to skin.
I also cut out the "piss" flap, I am not proud to say that I have pissed inside my pants because of this damnflap in my Joe Rocket 5.0 overpants. The Joe Rockets I wear as overpants only so I can pull them way down, these I wear as regular pants so I cannot pull them around my ankles....in public toilets for obvious reasons.
In my ride today it was quite cool and I'm not sure of the results. I have a pair that are unvented, I will have to try both back to back to see the real effectiveness of my venting.
FYI: Dupli-Color spray on bed liner does a good job of covering the grommets and sticking to the material. It seemed to add fair amount of time on the belt sander as compared to non bed liner treated material. The solvents in it might weaken the fabric so I'm not sure it would be wise to use it. I thought maybe I could use it to cover grommets in higher wear areas like the outside of the legs.
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