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Discussion Starter · #1 ·
After messing around with various rim tapes, including gorilla tape, and unsuccessfully retaining air for more than 48 hours, I found out that my stock Bontrager rims really need to use the rim strips. So I went to local bike store that stocks Trek and had them install the TLR rim strips. Rear tire is fine, front tire goes from 35 psi to about 20 psi in 24 hours and all air gone within 3 days. Same rim strip on both wheels (both wheels are stock), both have brand new Continental Mountain King tires. Rims are Bontrager Mustang Elite TLR 29". I used the Bontrager tire sealant as well. When I removed the tire from the rim to investigate, most of the sealant had coagulated around the sides of the rim where the Bontrager Round Base TLR Valve Stem was installed, though not where the stem seas in the rim strip (which appeared to be installed correctly).

The tire bead seats great one one side of the rim, but not very well on the other. The rim is asymetric and the rim strip appears to be correct for the wheel as well. The only thing I could see that may be anomalous is on the side where the bead doesn't set well, has a bit more plastic around the entire rim that seems to prevent the bead from sitting on the aluminum "shelf" and is likely pressed up against the plastic rim strip. This appears to be the proximate cause for it not holding air for more than a couple days. I don't know if I got a defective rim strip, or if it's the wrong strip - or something else entirely.

When I seat my tires, I use an air compressor to go up to 60 PSI to seat the bead, but guessing it only does the one side, as the tire was super easy to remove on one side when taking it off.

Any thoughts? What am I missing?
 

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Having set up multi-hundreds of Bontrager TLR wheels, I find that if there is an issue with holding air, it usually related to either the valve stem (incorrectly positioned on the strip or leaking from the valve itself), or damaged rim strip.
I always use a bit of soapy water around the bead of the tire while seating. This usually gets the bead set all the way around before hitting 50 psi.
If the tire is not fully seated, that can also be a source of air loss although less likely than the valve or strip.
 

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Double check the TLR strip to make sure it sits nice and snug along the rim edge where the tire hooks. Also, double check your valve to make sure it is sealing the valve hole and it is nice and tight (tighter the better).

If the strip is right, the valve is right, and the tire is a tubeless tire, you shouldn't have trouble seating it and it holding air.

On my personal Stache (no Bonty TLR strips), I just installed new tires and a similar air loss happened, which is normal. I deflated and debeaded the tire and then went to rebeading it. All good now. Sometimes the tire needs some persuasion. Eye up the bead line too to make sure it is all snapped in.
 

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Discussion Starter · #4 ·
Appreciate the quick replies. I can see that the side of the rim strip that doesn't seat the bead is a bit... 'imperfect'. I think I am going to chalk this one up to a bad strip and go get another this week. Good thing they are only $15.
 

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Eye up the bead line too to make sure it is all snapped in.
Money.

Trek rims tend to have a pretty tight fit dimension -- which really minimizes burping. Sometimes this makes the tire reluctant to pop up onto the bead completely, in which case it will never seal well.

After I mount a tire, I lightly soap up both beads using a mix of Dawn and warm water. Apply with a toothbrush. Then overpressure slightly and listen/look for that last POP of the tire fully coming up onto the bead shelf.
 

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Sorry to hear. I tighten valve stem finger tight and then a turn with pliers to secure. I put Stand sealant on inside of rim and outside of tire before setting bead, I set 1 bead by hand then the other using compressor. After I think it's set I bounce the wheel around, place on bike and go for a ride. I usually lose some air in first 24 hours but not after that. Good luck

Sent from my moto z3 using Tapatalk
 

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Money.

Trek rims tend to have a pretty tight fit dimension -- which really minimizes burping. Sometimes this makes the tire reluctant to pop up onto the bead completely, in which case it will never seal well.

After I mount a tire, I lightly soap up both beads using a mix of Dawn and warm water. Apply with a toothbrush. Then overpressure slightly and listen/look for that last POP of the tire fully coming up onto the bead shelf.
The soap and water have worked great for me as well. The TLR/XR combo has been maintenance free.
 

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Discussion Starter · #8 ·
Got a new rim strip from the LBS and popped it on. THe bead set on both sides at 50-60 PSI and I am going to see how long it holds air before putting sealant inside it. I've got it sitting at 40 PSI. If it holds there for a day, I'll remove the valve stem and put some Bontrager sealant in the tire and hope Bob's my uncle.
 
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