First, I’ll mention my success - a disc brake bontrager wheels with Pirelli P Zero tires. Spilled a small amount of sealant but otherwise successful. Easy enough it seems it couldn’t be difficult.
Pride comes before the fall - I moved on to my rim brake enve wheels and GP5000 TL tires. Had these set up last year so I know its possible. Struggled a lot last year but it was my first time. I try to get the tire seated before adding sealant but its just not happening. I have a sprayer that I’ve converted to a air tank but it seems to max out at about 50psi. I add soapy water to the rims. I add sealant, sometimes it helps. Adding the sealant is proving to be a puzzle. Silca sealant needs to be added to the tire directly since it will clog a valve - if the tire holds 75% of the sealant I’ve added then I feel successful. It appears possible to lose ALL the sealant while getting the tire to seal with the sealant added. Its a pyrrhic victory. Sometimes adding that sealant seems impossible. It just kept leaking here or there while pouring it in, despite my best efforts. I know silca excels at road tubeless but it has me considering my options.
I think last year I was able to simply pump like crazy to get the tires set up. Not sure what different this year. Perhaps the residual dried sealant from last year? I removed some but didn’t get fussy with it. Perhaps a couple of jagged edges of dried sealant are giving me hell.
I think my next move is to get an airtank so I can more reliably seat the tire.
Oh, things were reasonably reliable once I got them set up last year. I was hoping I was at the top of the learning curve.
Effeto mariposa has a powder additive for even better sealing (but I have stopped using it on my road bike because it clogs too much), so at least you can add that before adding the liquid sealant through the valve.
Anyway did you try removing the valve core to get the tyre seated, checked rim tape and valve?
If a tyre fails to seat and hold air without sealant it will not seat with period
I’ve seen almost all categorically terrible experiences with their product. Everything from drying out in less than a month, to clumping and unbalancing the tire, to dissolving rim tape.
I know some people run their wax with good results, but it’s quite the opposite on their sealant. Try literally any other product and it will be better.
I run the Vittoria sealant because it’s been tested with their inserts, but any ammonia free sealant is good for most applications. The Vittoria has glitter included so you don’t have to find your own to add (or deal with clumping strands).
I find it always harder to seat a used tyre. The dried sealant on the bead makes it sticky.
I’d try:
more soapy water (or just dishwashing soap). Make sure it goes on the bead and into the rim.
If you haven’t done so, take the valve stem out
Put wheel on its side to pump it up, no compressed tyre anywhere
-Try pulling/pushing the tyre in the spots where it won’t seat
I haven’t used silca sealant, but I’m always dubious about not being able to inject through the valve stem. It’s like a 3mm hole. Will it really not go through there?
Otherwise, I’d use another sealant. If you’re really sold on Silca, you could seat the tyre, and then when it’s on there a bit, pop one side back off and add the sealant.
I was trying to re-seat a used tire after changing the valve. I’d managed to seat it just fine when it was new. When I tried to re-seat it with a tubeless canister, I simply couldn’t do it. My LBS seated it in a few seconds with their shop pump.
Based on that, if you still can’t seat it … ask your LBS nicely. Or get a presta to schrader adapter and use a gas station air pump.
I’ve been able to setup a number of wheels tubeless with just a track pump … except Enve AG25. Biggest PITA ever! Had this been my first tubeless experience I probably would never have converted. The cassette was just as difficult, too!
Ended up paying my LBS to set them up tubeless. Lead mechanic had to tape the wheels with 2x layers in order to make them seal. I haven’t had a chance to put the wheels through their paces yet but hope it was worth it.
Never had any problems with their sealant, been using it on two bikes for the last year. Only had one puncture requiring a Dynaplug (shoulder slash). Otherwise works brilliantly, use the top-up once a quarter and fit new valve cores at the same time.