Overdraft

Hi!
trying to install Pirelli race tlr’s on Bontrager Aolus Comp 5 tlr rims…
compressor set to 100 psi
tire easily takes and holds 100 psi but when I let the pressure out to put the goo in the tire appears to be seated only on one side…
is it possible that the tire is seated enough to hold pressure but not ACTUALLY seated?
and if so, how much more pressure would be OK to add to get the second bead to seat?
or any other thoughts?
thanks!

WhyFi

You should always inspect the witness lines all the way around the wheel to ensure it's fully seated. Some tires, on some wheels, will unseat at low/no pressure.

Did you lube the beads of the tire? Doing so usually helps if it's not quite snapping in to place (you'll usually hear a "snap, crackle, POP!").

Overdraft

Ya, I’ve tried putting seating pressure in and although there was no audible pop you could see the carcass shifting as you’d expect it would look if it was climbing the step up.
I then tried letting most but not all of the pressure out and inspected the edges which appeared to be seated. Then I let the rest of the pressure out and looked again and clearly one side was unseated. So possibly this tire/wheel combo just unseats at zero pressure? Is that a thing?

WhyFi

Yeah, it's a thing, sometimes. You could see the witness line all the way around? It should be just above the edge of the rim. And what about bead lube? I usually just spray with slightly soapy water.

Overdraft

what are these “witness lines” you speak of?
so yes, I had a look and there are small ridges running the circumference of the tire which I assume are the witness lines and which were indeed lined up concentrically with the rim. and a further thank you because I was forced to examine the tires much more closely and therefore was able to determine that the damn tires are directional and that I put one on backwards

Overdraft

ok. correct direction!
on the bike and ready to go!
a bit late for a test ride other than around the culdesac. road report later!
lessons learned:
~after reading so much about how difficult it is to get tubeless tires onto your rims I was expecting a fight. for this tire wheel combo anyway it was super easy. on with thumbs, no fuss. off with 99 cent plastic levers.
~seating the beads with a 100 psi compressor was easy (once I figured out that they were seated, but then unseating when deflated)
~bought the syringe with the thread on tube on the end thinking loading the goo through the valve would be tidier. um, it can’t work. unless you can compress the air in the tire with the syringe (ps. you can’t) there’s no room inside the sealed system to add the goo. I guess if you did it when the bead wasn’t seated? In any event my solution was to pop the bead off for a few inches with my cheapo levers and use the syringe sans tube to squirt the stuff in.
~lots of chatter about how messy tubeless is. this is clearly from people who haven’t done an oil change on a sportbike recently. removing an oil filter buried behind the headers is messy… this was just a bit of goo that rinsed off with a hose in 2 seconds.

final question… how tight do you do up the valve cores? seems like they should be tight to hold air, but it would probably be easy to strip the allow stems…

WhyFi

The cores only need to be finger tight with the little core tool.

If you're uneasy about and/or inconvenienced by the tires coming unseated at no pressure, you could try an additional layer of rim tape. For that matter, are these rims taped or do they have the Bontrager rim strips?

Another approach, to make maintenance easier with tires that unseat, is to pick up some MilKit valves and a sealant syringe. The MilKit valves will pass the syringe "needle" through while holding enough pressure to keep the beads seated. Be careful, though - they'll also hold enough pressure to forcibly eject the syringe piston and all of the sealant... don't ask me how I know. So yeah, if you go that route, aim for 20psi or less.

DaveSSS 

To add sealant I let all of the air out, remove the core and use either a syringe or the tube that came on a bottle of orange seal. The tube fits over the valve stem. When using a syringe that won't pass through the stem, I compress the tire with one hand while slowly adding sealant. If sealant starts to run out, release your grip on the tire and it will suck the sealant in.

PeteHski

IME, they won't hold pressure at all unless fully seated.