- How much pressure should I use for a tire to settle on a rim?
- Is there need to glue the tire on the rim? (Or to try make it more airtight by any means.)
Nope, there is no need to glue the tyre on, the airtight seal is simply made by the rubber against the alloy. Many tyre fitters do use a sealing compound however, which helps to fill any imperfections in the wheel surface that might allow air to seep through them.
From my experience, the pressure needed to get the tyre to settle seems to vary massively depending on the individual combination of tyre and rim. I've seen some places have to go up incredibly high (90+ psi) to get them to pop on in the first place. Needless to say I was keeping well back until the fitter had dropped it back to normal worknig pressure (32psi in my case)
While you can force a reluctant tire on with more pressure, most tires should seat with 15 PSI, and forcing a tire on at a higher PSI has a higher risk of damage and danger to those nearby.
If a tire won't seat at 15psi, examine the rim and tire, reapply lubricant liberally on the tire bead and wheel rim, and position the tire so it's as centered as you can get it, then attach to seat it again up to 15psi. You should always use an appropriate lubricant for this process.
There is no need for a glue or sealant. If the bead of the tire or the rim is damaged you need to replace the bad item - a sealant or glue is insufficient. As long as the parts are in good shape, nothing other than a lubricant is needed.
It does not really matter what amount of pressure there is in your tires. What you need to take into consideration is that there is compatibility. Otherwise you are deemed to fail. To your second question, I wonder why you are thinking of gluing the tires to the wheel whether it is for your car or bike. I through back a question to you: Of what benefit will it be when you get to glue them together?