Wheels: JCW R105's (new)
Tires: General Exclaim UHP (new)
Sensores & Stems: Factory BMW/MINI parts (new)

Last week, right front went down (twice) - first time sensor was determined to have not been tightened, second time replaced stem (other stem appeared to not have the hard plastic washer between it and rim) and all seems to be well.

This morning, left rear down to 33 psi (others maintaining at 40 psi - max rating for tires is 51 psi) - no visible leaks, bubbles, etc. Reinflated to 40 psi and we'll see what happens. Tire was fine since Monday when I had everything rechecked after they replaced the front stem above.

This is becoming a major PITA.

Tires are inflated w/ Nitrogen. Any advise as to what might be happening? It's really affecting me work-wise because I have to keep running down to the tire place to get it taken care of.

What am I missing?

 

I also installed my General Exclaim UHP on Monday and there is leak problem, it's the sensor stems that didn't get tighten enough, after I re-tighten it, everything is fine, you might want to re-tighten it to be sure. Just my 2 cents

How's you like the tire. I am coming from the stock 16" bridgespoke with runflat to 17" 5 star pace with General Exclaim. I think the ride is like 20% to 25% better. Keep in mind that I am from 16" to 17", which is even more dramatic

 

Fill your bathtub up with water and place your tire inside of it to see where the leak it coming from.
With my tire it was coming from the edge of rim because the people that installed it, didn't do it right and left a tear on the bead of the tire where air would get out...

 

Must be mistaken

I was told if I bought nitrogen it wouldn't leak out

something about big molecules

 

Interesting as a diver nitrogen is my worst enemy because of the tiny bubbles that get into your blood stream.

The only thing I can say about nitrogen is that the heating and expansion rate differs slightly form normal air
which by the way is comprised of 78% nitrogen to 21% oxygen.
With that said, regular air is likely to leak before nitrogen only if cooled sufficiently to allow the air inside to
contract to a point where the seal around the rim might be broken.

 

Prost, can the stem be tightened at the base, or does the tire have to be dismounted and the stem tightened from inside?

So far, I LOVE these tires. I went from 15" to 18" with no noticeable difference in ride quality - probably due to the inexpensive 15's from the factory compared to the higher-end Generals.

The big selling point to me of Nitrogen was the lack of pressure change due to temperature (summer vs. winter, etc.). I was also told about the "less leaking", but I think they meant seeping through the actual tire sidewalls (on a moleculer level ).

I'm sure that if you have an actual leak (bad seal, puncture, etc.) the Nitrogen is no beter than the air.

 

Yes, you can tighten it from outside, the tire guy didn't need to dismount my tire. No air leak since he tightened it 4 days ago (finger cross ).

 

Great! I'll break out the deepwell sockets tomorrow.

Have a great Fourth!

 

maybe the valve core is loose?

 

I tightened the stems this AM. A couple, including the one in question, took about 3/4 -1 full turn to tighten, so hopefully that will fix it. Now, I just have to get a valve stem core tool. Can't hurt to check those as well.

Thanks for all of the input!

 

See above... fill your bathtub or the kitchen sink with water and put the tire in it... or if you have a pool put the tire in there. The bubbles will show you where the leak is quicker than all this guessing and pontificating. Hope you find it. A leak is a leak... air, nitrogen, doesn't matter, they'll both leak if you give them the opportunity.

 

I've been having the same issue, and just found that the valve stem on the tire that was leaking was loose.

Thanks for the info!

 

Instead of moving the wheels to the bathtub, you can also soak a sponge with soupy water and push the sponge around the valve stem to see is that the leak. That's how my tire guy found out what's my problem is

 

my wife would not like tires in bathtubs...

 

So far, so good. Everything is still holding air (while keeping fingers crossed!).