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Tubeless tire bead prep

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JackOfDiamonds

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Discussion starter · #1 ·
I really like tires that seal the beads with no sealant or minimal sealant. I hate sealant weeping everywhere until the beads seal 3 days later or never fully seal and need pumped up a lot and I always suspect it's the beads leaking.

I noticed some tires have pretty big mold lines on the tire beads and some even have sprues sticking out. Last time I noticed sprues I used a razor blade to add least cut off the sprues on the bead before mounting, but to me this stretches the definition of "tubeless ready" tires, so am I overdoing or overthinking it?

I just bought some Gravelking tires and the beads don't really have sprues sticking out, but they have big mold lines all over them, like waffles. It doesn't seem like a good formula for bead sealing. Should I take some sandpaper to the beads and sand out the mold lines?
 
#3 ·
I'm more generous with soapy water around the bead than I used to be. Years ago I would smooth off the mould ridges with a razor blade, but I've stopped doing that, in favor of making sure I've got some soapy water all around the edge prior to inflation, which seems to make for a more consistent seating of the bead.
 
#4 ·
I also trim all the mold lines and smooth any rough spots on the bead before I mount the tire. Never have any issues with beads not sealing up.
 
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Discussion starter · #6 ·
A day in the life...no sealing this on without sealant. Which tells me there's about a 50% chance it will never hold air day to day. I could remount it and meticulously razor blade off the hundreds of flashing lines on the beads but I might try rough sandpaper for the next one.
Image
 
Discussion starter · #8 ·
Yes it's a tubeless ready rim, and the bike right behind it uses the same rims and different tires and it did seal right up. So it's definitely the tires in this case.

I had a few rim/tire combos that sealed up with no sealant and held air overnight at least. And those are the ones that don't need pumped up ever day, which is a real pain on a commuter bike. So I'm trying to crack the code. Basically if the tire beads have lines, bumps, or giant sprues sticking out, the tend not to seal which is common sense, but I don't know what you can do about it or how to select tires that have smooth beads...maybe they need to start selling them as "super duper tubeless ready (we actually mean it).
 
Discussion starter · #11 ·
Yeah I'm not sure about these tires either; I didn't know they were going to be so knobby and I think I might want something that's more semi-slick in the center. And doesn't need to be quite so wide, maybe 45mm instead of 50mm, but I still want them to be light. Any suggestion?

The rims are Alex Adventure 2 rims, they are basically the cheapest tubeless-compatible rims and they are also not too heavy, and have eyelets. They've been pretty good to me.
 
#16 ·
JackOfDiamonds said:
A day in the life...no sealing this on without sealant. Which tells me there's about a 50% chance it will never hold air day to day. I could remount it and meticulously razor blade off the hundreds of flashing lines on the beads but I might try rough sandpaper for the next one. View attachment 1995919
Click to expand...
Did you use soap water on the beads, therefore preventing the sealant from doing its job?
U should "paint" the beads and rim hooks with sealant before seating the tire. It serves a lubricating, then sealing function.
 
#17 ·
“Did you use soap water on the beads, therefore preventing the sealant from doing its job?”

I don’t have any issues mixing the 2 solutions. Spray bottle with lightly soapy water - spray on tire sidewalls, blast air into tire with compressor, wipe everything down after bead pops into place, add sealant, (over) air up, short pedal down the street, adjust air pressure, ready to roll. Been working for me for me since 2008. YMMV.
 
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