Mountain Bike Reviews Forum banner
1 - 17 of 17 Posts

·
In my mind, I can do it!
Joined
·
2,365 Posts
Discussion Starter · #1 ·
This tube is practically new. Probably only 2 rides on it. Look at the pics, all of these patches are on the rim side of the tube. Before you say it.. I can't find anything on the rim that would make these holes. I even have new rim tape on the rim, the cloth velox brand. I can't find anything to make these holes and they are very tiny. So tiny that you can't even hear the hiss when you air it up. You have to hold it under water. Note the unpatched hole circled in black too...

Has anyone seen anything like this before? Is it possibly a bad tube out of the box?

 

·
Registered
Joined
·
4 Posts
I have the exact problem on my new bike after I changed the stock tyre.

Had two flats since then, all the holes were on the rim side, this problem seems to go away after I changed the stock rim tape.
 

·
Registered
Joined
·
2,814 Posts
bummer

Try a different tube or better rim tape; I had a similar issue and found that the rim tape glue was dry and allowed the tape to slide aside while installing the tire and allowing the spoke holes to damage the tube.
 

·
In my mind, I can do it!
Joined
·
2,365 Posts
Discussion Starter · #7 ·
Bikinfoolferlife said:
Tubes aren't exactly a high quality control item...they're cheap, sometimes you get a bad one.
It's a slime lite tube. Not that cheap really. $13
 

·
In my mind, I can do it!
Joined
·
2,365 Posts
Discussion Starter · #8 ·
lkoky said:
I have the exact problem on my new bike after I changed the stock tyre.

Had two flats since then, all the holes were on the rim side, this problem seems to go away after I changed the stock rim tape.
Yeah, I was having pinch flats with the stock rim tape that were a tape width apart. That's why I replaced it with the velox. Maybe the velox isn't that great a tape though???
 

·
Registered
Joined
·
6,762 Posts
Velox makes good rim tape....

my suggestion would be to pull the tape and closely inspect the rim, spoke heads (or spoke holes if it's a double wall rim), etc. That deffinately looks like a problem with either the tape or the rim itself. Look for any burs or sharp protursions that may stick through the rim tape or work through the tape with the tube installed and pressurized. A bur or nick in the spoke bed area may not show up with fresh tape over it, but may work through the tape with pressure on it.

My guess that you will find spoke heads or access holes with burs on them that poke through the tape. This can be fixed by takinig some fine grit sand paper to the burs. Painstaking and time consuming, but the only way to fix the problem other than going with that nasty plastic rim tape.

As Bikinfool says, tubes aren't exactly a high quality item as far as QC goes. But your problem seems too consistant to be just a bad tube. You could try changing out the tube and seeing if you get the same results. That would confirm it one way or the other. But I'd be willing to bet the problem probably isn't the tube, but the rim itself.

Good Dirt
 

·
In my mind, I can do it!
Joined
·
2,365 Posts
Discussion Starter · #10 ·
Squash said:
my suggestion would be to pull the tape and closely inspect the rim, spoke heads (or spoke holes if it's a double wall rim), etc. That deffinately looks like a problem with either the tape or the rim itself. Look for any burs or sharp protursions that may stick through the rim tape or work through the tape with the tube installed and pressurized. A bur or nick in the spoke bed area may not show up with fresh tape over it, but may work through the tape with pressure on it.

My guess that you will find spoke heads or access holes with burs on them that poke through the tape. This can be fixed by takinig some fine grit sand paper to the burs. Painstaking and time consuming, but the only way to fix the problem other than going with that nasty plastic rim tape.

As Bikinfool says, tubes aren't exactly a high quality item as far as QC goes. But your problem seems too consistant to be just a bad tube. You could try changing out the tube and seeing if you get the same results. That would confirm it one way or the other. But I'd be willing to bet the problem probably isn't the tube, but the rim itself.

Good Dirt
The rim is a double wall rim and when I put the new tape on I did inspect the spoke heads. All the heads were about 3 or 4mm below the surface of the second wall. If the rim doesn't flex enough to have a spoke poke up that far I don't see how a bur could be a factor. Do the rims work this way? If so I may need to take my drimmel to those heads.
 

·
Registered
Joined
·
12,083 Posts
From the look of the patches centered inside of tube. I think you gotta suspect the spokes or spoke holes allowing the thin wall tube to bulge into?

What do the punctures look like. smile, poke, circle?
 

·
In my mind, I can do it!
Joined
·
2,365 Posts
Discussion Starter · #12 ·
jeffscott said:
From the look of the patches centered inside of tube. I think you gotta suspect the spokes or spoke holes allowing the thin wall tube to bulge into?

What do the punctures look like. smile, poke, circle?
tiny pin holes like maybe what a cactus would make or even something smaller. Actually come to think of it I could rake my fingernail across it and feel the rubber edge so it's probably more like a cut than a puncture.
 

·
In my mind, I can do it!
Joined
·
2,365 Posts
Discussion Starter · #14 ·
Squash said:
my suggestion would be to pull the tape and closely inspect the rim, spoke heads (or spoke holes if it's a double wall rim), etc. That deffinately looks like a problem with either the tape or the rim itself. Look for any burs or sharp protursions that may stick through the rim tape or work through the tape with the tube installed and pressurized. A bur or nick in the spoke bed area may not show up with fresh tape over it, but may work through the tape with pressure on it.

My guess that you will find spoke heads or access holes with burs on them that poke through the tape. This can be fixed by takinig some fine grit sand paper to the burs. Painstaking and time consuming, but the only way to fix the problem other than going with that nasty plastic rim tape.

As Bikinfool says, tubes aren't exactly a high quality item as far as QC goes. But your problem seems too consistant to be just a bad tube. You could try changing out the tube and seeing if you get the same results. That would confirm it one way or the other. But I'd be willing to bet the problem probably isn't the tube, but the rim itself.

Good Dirt
This is just nuts. I had another flat this time on my front rim. Same thing, the hole was on the rim side. I checked where the hole was in relation to the valve stem and there is absolutely nothing there to poke a hole. The rim tape is stuck tightly there are no share objects poking through. I just don't get this. It makes no sense. But so far I have had about 6 or 7 flats all as a result of something between the rim tape and the tube. Something isn't right here and I can't explain it.
 

·
Old man on a bike
Joined
·
12,395 Posts
All I meant the first time around was like Squash says, not a high QC item. Now I'm surprised to see they were slime tubes and the slime doesn't patch such small holes?
Did you try airing up these tubes before installation by any chance to see if they were bad on their own? Are these flats all on the first pair of tubes? Have you tried using a regular tube and seeing if it flats the same way? Got pics of your rims/tape? Just grabbing straws here, but I've yet to even bother with a patch on any slime tube I've used, let alone have any tube fail from a smooth and well taped rim surface.
 

·
In my mind, I can do it!
Joined
·
2,365 Posts
Discussion Starter · #16 ·
Bikinfoolferlife said:
All I meant the first time around was like Squash says, not a high QC item. Now I'm surprised to see they were slime tubes and the slime doesn't patch such small holes?
Did you try airing up these tubes before installation by any chance to see if they were bad on their own? Are these flats all on the first pair of tubes? Have you tried using a regular tube and seeing if it flats the same way? Got pics of your rims/tape? Just grabbing straws here, but I've yet to even bother with a patch on any slime tube I've used, let alone have any tube fail from a smooth and well taped rim surface.
Well, there is a logistical issue with slime tubes and holes you know. In order for it to work the holes need to be on the outer part of the tube. That is where the slime is going while the wheel is spinning. Down at the rim side, hardly any slime is there.

Best I can figure on this is that either the tubes are defective or possibly small grains of sand stuck to the tape are enough to wear a hole through the tube. I found about 3 or 4 small grains of sand on the tape surface last night.

On a good note though, I emailed Slime and they replied saying they would send me a couple of new tubes and they wanted to know if I would sent my tubes back to them so they could investigate the issue. At least they are willing to do something and that says a lot. :thumbsup:
 
1 - 17 of 17 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top