Originally Posted by BCRider
Even if the cores are not removable why not just squirt the sealant into the tire directly instead of through the stem?
But more importantly if you put the sealant into the tire you're going to have a VERY messy situation when you ever want to remove the tire. I'd suggest you don't bother and just carry a patch kit to fix the tire in event of a flat. After all from looking at the info on these wheels the point is to produce a lighter setup than that found with a tube and tire. Adding sealant would defeat the point of keeping the wheels and tires as light as possible where you worry about such things to the point of not using even a light latex or vinyl tube.
As for the stem and core options I'd suggest you email the makers of these wheels directly since this is such a specific wheelset and stem that "general" methods don't mean much if it turns out that the stems you have use a permanently sealed in valve core.
First, I don't have any experience with Fulcrum road tubeless wheels. I've used Stan's Notubes tubeless system on mountain bikes for nearly ten years, and have loved it. When I first started using Stan's, it was new and seemed crazy to most folks. Now, in the mtb world, Stan's system and tubeless systems in general are pretty much accepted as the way to go for most off road situations.
Now, for road tubeless. I had a hard time getting my head around why this would be a good thing, really. I still haven't used it.
But my shop is a Stan's Notubes dealer (selling mostly mtb tubeless products, not road). And my business partner in the shop has decided to try road tubeless, and invested in a set of Stan's Notubes road wheels and the accompanying Hutchinson tires. These can be run at normal road tire pressures, but for a lot of folks it may be tempting to run them at a bit lower pressure than normal for better ride quality (with no worry of pinch flats, of course).
I've always been aware of the pitfalls of using a tubeless system, particularly a "converted" conventional mtb rim/tire, at pressures above about 40psi. So this whole thing of using road tubeless at 100+psi had me a little wary. However, with the specially designed Stan's wheels along with the tubeless-ready tires, it works with no problems and the tires air up just as easily as tires with tubes!
Okay, so I'm impressed with that. But what about flat protection? The need for sealant? Okay, and again, I haven't used a road tubeless sytem.....yet. As for my business partner, he's done probably a dozen rides so far on the new wheels/tires, with Stan's sealant installed, with no flats. Certainly not enough time on the system to declare them practically "flat free" like I declared Stan's mountain bike tubeless system years ago.
But check out this video. For the road tire getting poked with sharp things and staying inflated, fast forward to about 2:30 in the video. Good ol' Stan showing off his products once again.
So to sum up, you use the sealant in road tubeless for the same reason you do on mountain bikes: to prevent flats.
actually, once you click on the link, you'll have to click on the "puncture demo" video at the bottom and then fast forward to 2:30 for the road tire getting punctured.