I said it before I will say again looks like anything goes at lost trails as long as you got a helmet and eye protection. I seen three kids on one quad at same time more than once none of my three wheeler have a spark arrestor no one every looked or inspected any of my trikes and one is a total pos load got only a half rear fender no brakes no front fender rusted out loud muffler no one even gave me second look I am local ride there often.
From my experience there, Spark Arrestor is the key. Noise never really an issue from what I've seen. You should be fine. Also have had numerous bikes and quads up there including my Banshee which is 2-stroke and had wide open Toomey Pipes. đź‘Ť
I had a 850 with a big gun exhaust no one said a word.
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