Issues with getting a tyre to seat properly in the rim...

[andyoxon]

Having refitted a tyre I'm finding that a portion of the tyre is not seated correctly and 'retained' in the rim (Sputnik 36h) relative to the rest of the tyre.  Happened on a ride recently, with old tyres, following a p*ncture fix, and meant that I could feel the bump of the uneven rotating wheel-tyre diameter.  Took ages to try and get it sorted out, including wetting the rim prior to reinflating hard.  I needed new tyres anyway, and I've bought Paselas 700x28c again, plus schwalbe rim tape (20mm) / 18-25c inner ts, and still struggled to get the tyres to seat properly.  I managed it inside with washing up liquid on tyre/rim plus track pump 90psi, but it's a pain out on the side of the road.

How common is this, what are the root causes, and any tips out there?

[Torslanda]

A smear of swarfega or a soap solution will work. Clean the tyre bead and the rim first.

In difficult cases I sometimes resort to inflating the tyre in stages and working the bead to encourage it to seat. Once a 29er was so tight it needed 80 psi to seat but that was on tubeless ready rims...

[robgul]

My trick is to inflate the tyre to about two-thirds the desired pressure and then let it down again (poke a small Allen key into a Schraeder type valve and hold it) - then go round the tyre squeezing the cover into the bead - then reinflate to the correct pressure.   You may also find that you need to push the valve stem into the cover and pull it out again to ensure that the thicker rubber area on the tube around the valve is inside the bead (especially on narrower tyres)

Rob

[Brucey]

some tyres are just tight on some rims.  LBS have various tools and tricks to help tyres seat, which are not roadside friendly, but needs must.... I'd use different tyres and/or rims on tour, otherwise it is only a question of putting up with a badly seated tyre until you get home...

Often you can improve matters by using a thinner/more slippery rim tape (on a rim that that has a curved well rather than distinct shoulders). Some (esp folding) tyres are sometimes 'difficult' first time round but then get easier as time goes on.

Some handy tools for workshop use are

1) a cheap trigger spray bottle that is filled with soapy water, for lubricating tyre beads; just deflate and spray away.
2) tyre pliers, a bit like this;


Such things can be bought (not sure who makes them right now, probably Park Tool) or DIYed.   If using them on lightweight /skinwall tyres, it is a good idea to use a piece of old inner tube (maybe two layers) to protect the tyre as it is manipulated.

cheers

[andyoxon]

Thanks T, r & B. 

We have a few of those little hand sanitiser type bottles around, so I'll put a small volume of soap solution in one to take on the road with me' just in case.  Actually, perhaps hand-sanitiser itself may work...