The seat cover may include installation instructions. I installed a nos Travelcade/Saddleskins seat cover which suggested using 3M Super 77 spray adhesive, so that's what I used. The seat cover instructions said to apply the adhesive only to the top of the seat foam, not the sides. Test fitting before spraying is a good idea >> I temporarily installed the seat cover to check the fit, snagging the front & rear of the cover on the seat pan prongs.
Prep. First thing, though, is the prep. I cleaned up the old seat foam as good as possible & used sandpaper to remove some of the old dried up crud. The seat foam was separated from the pan in a couple of spots, so I re-glued it with the Super 77 & let it dry overnight.
Prongs. The seat pan has sharp prongs all around that hook the seat cover >> I pried those out at about 45
o. Don't over-pry them as I guess some could break off. My pan was in good shape, so I didn't bother treating the little bit of rust it had & I didn't both painting it to protect against rust. maybe next time I will.
Install. The saddleskins material was stretchy which seemed to help & the pattern was an exact match to the old seat cover. My seat has a front section & a rear passenger section, plus a transition section. I sprayed the top of the seat foam at the transition, then started the installation, using the transition seams to help in the alignment. The markings in the old foam also help. You have to pull the seat cover over the prongs which I guess should poke thru the seat cover. This was kind of hard. The prongs made marks in the material, so I used an awl to poke holes at the indentation marks, then poked the prongs thru the holes, using a flat blade screwdriver to push the material onto the prongs. Then did the rear section in the same manner, then the front. After the cover is installed, press down all of the prongs back to their original position.
Something else. I wasn't sure if the seams were waterproof, so I applied Liquid Electrical Tape to the seams using a large medical syringe & let it dry overnight. I kind of got the idea from wiredgeorge who used the stuff to repair a cracked seat cover.
Liquid Electrical Tape.
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