Ask a Mechanic: Installing a Marsh Guard Fender on a Mountain Bike Ask a Mechanic: Installing a Marsh Guard Fender on a Mountain Bike Greg O'Keeffe2015-12-11T10:56:56-08:00 Trevor says, “ I've seen a few people with marsh guards on the trail Ask a Mechanic: Installing a Marsh Guard Fender on a Mountain BikeGreg O'Keeffe2015-12-11T10:56:56-08:00