Please take precautions if you have a latex sensitivity.
Work surface preparation and installation precautions
1. Use a very clean work area to do the installation of your FattyStripper. The latex tends to have a slight static charge that attracts particles. If those particles are hard or sharp, they can poke holes in the thin FattyStripper after the pressure of inflation is applied.
2. Do not set the FattyStripper down on the bench or anywhere where they can pick up debris.
3. Wipe the FattyStripper clean before installation.
4. Do not let the rim contact the bench or floor with the FattyStripper wrapped over the bead. Not only can it pick up debris, but the bead can cut the FattyStripper before you are ready to trim the excess.
FattyStripper Installation Instructions
1) Rim preparation - make sure you have your rims reasonably clean and solvent free. A weak dish soap solution and a rag seems to work the best.
2) Install the inner rimstrip. This can be the plain, ugly, vinyl rimstrip that comes with your rim or one of our gorgeous 3M BlingStrips. Something is required to reinforce the rim at the cutouts since the FattyStripper is meant just to seal your rim and is not structural.
3) If installing the BlingStrip, you will need to trim the width of the BlingStrip to fit snugly between the "shoulders" of the rim. It should completely cover the cutouts with at least 3/8" (usually more) of material on the outside of the cutouts to keep it from pushing the edge of the strip out of the cutout once the tire is inflated. Large, sharp wrinkles should not be formed once the strip is pulled tight around the center of the rim.
4) If installing the BlingStrip, only peel back enough of the adhesive backing to secure the overlapped section (3"). I usually don't strip the backing material at all, thus making sure that the strip's adhesive doesn't make contact with the FattyStripper. Line up the inner exposed edge of the BlingStrip with the metal of the rim an inch or two from the valve hole so that the overlapped section will be where you put the valve hole. The BlingStrip will last longer and look better if its edge is not exposed at one of the rim's cutouts. The DT Swiss/Specialized rims have thin horizontal strips of metal... put the exposed seam "behind” one of those strips of metal instead of the slanted section of metal.
5) Recommended optional step - Cut a 1/2" section of an old 700c road tube to use as a spacer/gasket for your tubeless valve stem. Most tubeless valve stems were made for standard double wall rims where the thickness from the inside of the rim to the outside is more than a few millimeters. Most fatbike rims put the valve hole through one width of metal. A commonly overlooked problem with this is that the valve stem's rubber pulls through the hole enough to cause the locking nut to run out of threads before it can adequately tighten the backing rubber to the hole. This allows air leaks. Use a hot nail to burn a hole through both layers of the old bike tube. Again, please don't inhale the highly toxic puff of smoke... and preferably do this outside. Push the valve stem through the tube's hole.
6) Line up the reinforcing rimstrip's valve hole with your rim's valve hole. If using a BlingStrip, a hot nail going from the inside of the rim, through the valve hole, melts a nice clean hole through both layers of the BlingStrip's overlap. Don't inhale the puff of smoke... please.
7) Using a clean, damp rag, wipe the rim to make sure it is completely free of debris before installing the FattyStripper over the rim.
8) Insert your tubeless valve through the latex FattyStripper and then insert through your rim's hole. Stretch your FattyStripper evenly over both beads all the way around the rim. Finish by relaxing the band around the rim and eliminate all wrinkles. Make sure that the latex is not pulling in any direction right at the valve.
9) Put nylon spacer & locknut onto valve and tighten the lock nut while pushing on the back of the valve stem with your thumb.
10) Be careful not to set the wheel down in such a way that the metal bead can slice the FattyStripper that is wrapped over its edge.
11) Soap/lube the FattyStripper slightly to allow the tire to easily slide up the shoulder and seat on the bead. I use common liquid dish or laundry soap to lube the bead shoulder. Not only does it make a decent lubricant, but if you do have slight leak, its nice to see the bubbles. Vaseline, coconut oil or a white lithium grease works fine too. Using your finger, put a thin coat of lube on the FattyStripper from where the tire gets tight on the rim to the bead. In the cold winter months, I've put a thicker application of lube and have run my tires tubeless, without ANY sealant for weeks at a time. During warmer months, the lube doesn't seal the bead as well... so sealant is required. Once the bead has bonded with the latex... nothing is needed.
12) Place your tire onto your rim. After I put both sides of the tire onto the rim, I usually utilize a tire bar to open a slight gap so that I can cleanly squirt 1 or 2 oz of Stan's sealant into the tire. I've NEVER needed more than 3 oz to seal up tire... and that was only because the tire itself had over a hundred pinholes up the sidewall and required a few days of doing the "sealant" wobble to get the tire fully sealed.
13) Slowly spin the tire at a 45 deg angle to the left and to the right to put a coat of sealant around the tire. If a little spills out... that's OK, but usually its not more than a drip or two. This step will help you seat the bead.
14) Remove the valve stem's core. This is a MUST DO step to get the bead to seat.
15) Seating the bead can sometimes be a little tricky for some rims. IF your rim has a small bead shoulder, the tire is super loose or the tire sidewalls are very still (non-120tpi), I have had excellent luck using the 1" webbing from a standard ratchet strap and wrapping it around uninflated tire 2x. Separate each wrap around the tire by an inch or so to put pressure evenly near each tire bead. I do not use the ratchet. I just pull both ends tight with my hands and then hold it with my hand. This allows me to slowly release the strap when the air pressure is building and expanding the tire.
16) Using compressed air, "hit" the valve with a blast of air until the tire seats. Let the expansion of the tire push the webbing out slowly.
17) Inflate up to 10-15 psi. You should hear the tire "pop" out to the bead. You can visually inspect both sides of the tire to make sure the tire's bead is consistent looking all the way around. This will indicate that the tire is fully seated. If it is not, use your thumbs to "work" that section of the tire until it slides out and fully seats. Most rims are rated for 20 psi MAXIMUM. DO NOT EXCEED 20 psi EVER. This is extremely dangerous for you and will destroy your rim in a non-warranty-able way. If you cannot get the bead to seat, release the air pressure, carefully push the tire back from the bead where it isn't seating and smear some lube in there. Try re-inflating while working that section with your thumbs.
18) Spin and/or wobble the tire to ensure that the entire inside of the tire and rim gets coated with sealant. Mount the tire and go for a quick ride is also a great way to get it fully sealed.
19) Using a sharp pair of fabric scissors or the sharp point of a razor blade, trim the excess by pulling firmly on the FattyStripper to stretch it away from the tire and slide your blade along the edge of the metal rim. The latex will retract behind the metal rim leaving minimal latex visible, if any.
Here is a link to the $1.29 Snap Blade razor I have been using from Ace Hardware.
20) Mount the tire and go ride.
21) New tires often take a few days to fully seal... due to the pinholes in the sidewalls inherent to the tire's manufacturing process. In my experience, the lighter the tire, the more pinholes there will be. Just re-inflate each day and do the "sealant wobble" to coat the inside of the tire with sealant.