[cooskull]

A few months ago I got some new Pacenti SL23 rims and carefully applied 2 layers of Stan's tape before mounting some tubeless tires. Tire mounting issues aside, I inflated the tire and seated the beads easily the first time using just a floor pump. This weekend I was due for some new tires so I got some replacements and put them on. Not only would the beads not seat with a floorpump, a very manly high CFM air compressor couldn't get the job done either. No amount of soapy water or fiddling around with the tire made any difference.

Eventually I figured out why I couldn't get them inflated. After several months of exposure to 80-100 PSI pressures the Stan's tape had deformed/stretched enough so that relatively deep dimples formed in the spoke holes. Due to the Pacenti's very tight tire fit and the off-center drilling pattern, the tire beads inevitably end up sitting right in the middle of these dimpled spoke holes in the center channel. When you try to inflate the tire and seat the beads, all the air just rushes out these dimples- it's the proverbial rabbit hole under the fence times 28 and 32. Finally I caved in and just bought and re-applied the Stan's yellow tape and sure enough, the beads seated easily with a floor pump.

Sooo... any thoughts about how to avoid this issue? I don't want to have to spend an additional $5 per wheel on Stan's tape every time I have to remount a tire, not to mention the extra time hassle to remove and re-apply the tape. I know other people use alternatives to Stan's, but if they eventually stretch as well the end result will be the same. Veloplugs aren't an option due to the Pacenti's already very tight fit. FYI I stretch the Stan's tape out as much as humanly possible when applying it to the rim.

Note: I'm not trying to flame Pacenti here, as except for tire mounting issues, I am extremely happy with the rims. I can imagine this is a common problem with other tubeless ready rims as well.

 

[Blue CheeseHead]

Contributing to the problem may be that the rim tape is sticky from the sealant thus not allowing the beads to slide out and connect the rim. Make sure the rim tape and tire bead is clean of sealant. A thicker soapy application on the rim tape and bead may help lubricate it.

If that does not work, try 3 layers of Stans next time. I did that on my HED's when 2 layers of the original tape failed at a spoke hole flatting my tire.

 

[cooskull]

Sealant stickyness isn't an issue as I scrub the rim with a nylon brush to get rid of any latex residue during tire changes.

Putting 3 layers of tape would probably help lessen the stretching, but I'm worried that the extra layer would make the already "challenging" tire mounting process on the Pacenti SL23 (there are numerous threads on this) become nearly impossible.

A thicker mounting lube would probably help temporarily plug the dimple gaps, my only concern on this would be if the extra lube would interface or interact with the added sealant once the bead is seated. I guess if the lube is water based and if the sealant is latex based, this shouldn't be an issue.

 

[Blue CheeseHead]

Sealant stickyness isn't an issue as I scrub the rim with a nylon brush to get rid of any latex residue during tire changes.

Putting 3 layers of tape would probably help lessen the stretching, but I'm worried that the extra layer would make the already "challenging" tire mounting process on the Pacenti SL23 (there are numerous threads on this) become nearly impossible.

A thicker mounting lube would probably help temporarily plug the dimple gaps, my only concern on this would be if the extra lube would interface or interact with the added sealant once the bead is seated. I guess if the lube is water based and if the sealant is latex based, this shouldn't be an issue.

Some might wonder why a man that regularly sports spandex keeps a tube of KY in his tool box. :blush2:

 

[tednugent]

A few months ago I got some new Pacenti SL23 rims and carefully applied 2 layers of Stan's tape before mounting some tubeless tires. Tire mounting issues aside, I inflated the tire and seated the beads easily the first time using just a floor pump. This weekend I was due for some new tires so I got some replacements and put them on. Not only would the beads not seat with a floorpump, a very manly high CFM air compressor couldn't get the job done either. No amount of soapy water or fiddling around with the tire made any difference.

Eventually I figured out why I couldn't get them inflated. After several months of exposure to 80-100 PSI pressures the Stan's tape had deformed/stretched enough so that relatively deep dimples formed in the spoke holes. Due to the Pacenti's very tight tire fit and the off-center drilling pattern, the tire beads inevitably end up sitting right in the middle of these dimpled spoke holes in the center channel. When you try to inflate the tire and seat the beads, all the air just rushes out these dimples- it's the proverbial rabbit hole under the fence times 28 and 32. Finally I caved in and just bought and re-applied the Stan's yellow tape and sure enough, the beads seated easily with a floor pump.

Sooo... any thoughts about how to avoid this issue? I don't want to have to spend an additional $5 per wheel on Stan's tape every time I have to remount a tire, not to mention the extra time hassle to remove and re-apply the tape. I know other people use alternatives to Stan's, but if they eventually stretch as well the end result will be the same. Veloplugs aren't an option due to the Pacenti's already very tight fit. FYI I stretch the Stan's tape out as much as humanly possible when applying it to the rim.

Note: I'm not trying to flame Pacenti here, as except for tire mounting issues, I am extremely happy with the rims. I can imagine this is a common problem with other tubeless ready rims as well.

No issues with Stan's rims, with mounting and remounting....

how are you holding the rim & tire, to promote the rapid initial seal? This has a huge impact on getting tires to seat into the bead hook

 

[cooskull]

Some might wonder why a man that regularly sports spandex keeps a tube of KY in his tool box. :blush2:

My wife already believes I spend too much time in the garage with my bike. If she found KY in my toolbox, I'd have some difficult explaining to do!

I also might try some Kapton tape that others have recommended in this thread. Since it's reported to be thinner than Stans, maybe 3 wraps would be feasible.

 

[cooskull]

No issues with Stan's rims, with mounting and remounting....

how are you holding the rim & tire, to promote the rapid initial seal? This has a huge impact on getting tires to seat into the bead hook

I usually have one hand wrapped around the tire and rim by the valve stem, while I use the other to hold the air chuck. Also I just let the tire/rim sit on the ground rather than hanging it from the rim somewhere.

I'm not sure I'm following you: If the bulk of the air was leaking from around the valve stem I could see how holding the tire around the valve stem area might make a difference. But in my case the air seems to be leaking pretty much equally all around the rim from all the dimples in the spoke holes- how would holding the rim/tire a certain way affect inflation in this case?

 

[tednugent]

There's special little tricks to help you get the tire to seat, whether you use a floor pump or compresssor

letting the tire sit on the ground can hinder the seating of the bead, so you want to hang the rim or hold the wheel in the air.

 

[cooskull]

There's special little tricks to help you get the tire to seat, whether you use a floor pump or compresssor

letting the tire sit on the ground can hinder the seating of the bead, so you want to hang the rim or hold the wheel in the air.

Any other tricks you recommend other than not letting the wheel sit on the ground when inflating? Searching the interwebs on this specific topic did not result in any eureka moments for me. Ironically it seems loose fitting tires usually present a bigger problem than uber tight tires which are my case.

- I made sure the tire beads where on on either side of the valve stem.
- I had the valve core removed for maximum air flow when using the compressor.
- I tried to manipulate the tire such that at least one side of the tire was sitting on the bead shelf, but due to the extremely tight tire fit, the bead would quickly fall back into the center channel.

 

[ergott]

Are you trying to reseat the tire with sealant already in there? The sealant should take care of the gaps you are talking about. I've reseated tires on rims with old tape all the time.

 

[SauronHimself]

There are some people who claim Gorilla Tape is a cheaper but just as effective alternative. Those who use it say one or two layers suffice.

 

[Enoch562]

Any other tricks you recommend other than not letting the wheel sit on the ground when inflating? Searching the interwebs on this specific topic did not result in any eureka moments for me. Ironically it seems loose fitting tires usually present a bigger problem than uber tight tires which are my case.

- I made sure the tire beads where on on either side of the valve stem.
- I had the valve core removed for maximum air flow when using the compressor.
- I tried to manipulate the tire such that at least one side of the tire was sitting on the bead shelf, but due to the extremely tight tire fit, the bead would quickly fall back into the center channel.

I use a rubber tipped blow nozzle with the valve core removed. It can deliver a lot of air volume when they are hard to get up on the bead. After It jumps on it, I just cover the stem with my finger then I quicly slip the core into place.

 

[cooskull]

Are you trying to reseat the tire with sealant already in there? The sealant should take care of the gaps you are talking about. I've reseated tires on rims with old tape all the time.

My install procedure has been to install the sealant through the valve after the beads have been seated, because this is the technique recommmended by many people/sites (Stan's for one) and it seems the least messy. It doesn't seem that my sealant is much more viscous than just soapy water, but I'll be sure to give this a try next time.

Edit: I do fall into the clydesdale category so maybe the combination of the large number of spoke holes (32 rear) and the higher PSI (95ish rear typically) deforming the tape more results in a more difficult install than an the average user.

 

[cooskull]

There are some people who claim Gorilla Tape is a cheaper but just as effective alternative. Those who use it say one or two layers suffice.

I know using Gorilla tape is pretty popular with MTBers but maybe not so much with the road tubeless crowd. I believe it's relatively thick which would be a deal-breaker in my particular case.

 

[farva]

American classic tubeless kit uses a thin strip of strapping tape over the spoke holes before applying tubeless tape. Would add minimal thickness in the spoke bed area only. Might help with your issue

 

[tednugent]

American classic tubeless kit uses a thin strip of strapping tape over the spoke holes before applying tubeless tape. Would add minimal thickness in the spoke bed area only. Might help with your issue

View attachment 301210

Strapping tape is also a popular alternative at MTBR as well

 

[Blue CheeseHead]

There are some people who claim Gorilla Tape is a cheaper but just as effective alternative. Those who use it say one or two layers suffice.

The problem with Gorilla tape in this application is thickness. It is substantially thicker than Stans and the OP's tires are already tight.

(OP beat me to it. )

 

[Blue CheeseHead]

My install procedure has been to install the sealant through the valve after the beads have been seated, because this is the technique recommmended by many people/sites (Stan's for one) and it seems the least messy. It doesn't seem that my sealant is much more viscous than just soapy water, but I'll be sure to give this a try next time.

Edit: I do fall into the clydesdale category so maybe the combination of the large number of spoke holes (32 rear) and the higher PSI (95ish rear typically) deforming the tape more results in a more difficult install than an the average user.

Sealant in before seating is just going to make a big mess. Too much air velocity and too big of gaps.

 

[tednugent]

Sealant in before seating is just going to make a big mess. Too much air velocity and too big of gaps.

If you do it properly, no mess, and it's not hard to do it properly either.

 

[cooskull]

Thanks for the tips guys. Next time I'll try adding sealant before trying to seat the beads, and I'll probably pick up some Kapton and/or strapping tape to have on hand as plan B.