nayr497

I've been having problems with my Vredestein latex tubes for awhile now and I'm about to lose my mind. Had a wheelset built up about a year ago and have probably had 10+ punctures since. I absolutely cannot figure out the issue and I'm about to lose my mind.

I've had a few plain ol' punctures on the road from riding, but last week I inflated the tire at home, prior to a ride, and about an hour later (sitting on a bike stand) heard it explode. There is a small tear/cut right at the tube seam, about 2 cms from the valve stem. I removed the tire/tube and examined the wheel. The Velox tape is intact, no spokes poking through and the inside of the rim is smooth. My ONLY guess is that it *maybe* is pushing into the valve opening. However, it's not right at the valve, so that seems unlikely.

Around 90% of the 10+ punctures have been at the seam near the valve. This one was an actual tear, whereas most of them were more like a small pin prick. Those had led me to believe I got a bad batch of tubes. But this actual rip seems to indicate something else.

At around $15 a tube, this is starting to become an expensive issue. I'm losing my mind trying to figure out what is causing the punctures. Oh, and not an installation error. I make sure the entire tube is inside the tire before inflation AND the punctures are happening in the middle of the tubes, not at the edge.

trailangel

Here's my take, but know-it-alls will correct me soon.
I road on tubulars for over 10 years... never any problem with the latex tubes.
Bought clinchers and tried latex tubes. Had problems at stem.. latex coming apart.

I think latex deteriorates rapidly when stored in a box or out of the tire. You don't know how old they are when purchasing. They are fine in sewn up tire.
So now I use Continental Race Light butyl tubes... they are about the same weight.

OneIsAllYouNeed

What widths are the rim, tire, and tube? What pressure are you inflating to? I've seen similar issues with tubes that are nominally much narrower than the tire.

Do you store the tube such that there's no stress on the valve stem? Rolled up tubes can take quite a beating stuffed in a seat bag.

nayr497

I just decided to give Vittoria latex tubes on my other bike, paired with Vittoria Corsa clinchers. Ksyrium SL wheels. Put them in last week, two rides, no issues.

The wheel (it's almost always the rear) I'm having the issues with was handbuilt by a trusted shop. Ambrosio Excellight rims, Velox cloth tape, Vredestein tube, Vittoria Corsa tires.

Here is the other crazy thing I forgot to mention: I've put in a butyl tube after a puncture on the road...and they were fine for multiple rides. Is there any way a butyl tube is that much tougher then latex and the rim issue tears latex but not butyl? That seems crazy! Especially since latex is supposed to stretch more. But maybe they're more fragile? This seems to shoot down the idea that it's a rim issue. But the last tear came at home, not on the road.

For me, it's not about weight saving, I love the feel of nice tires with latex tubes. I just would like to stop this madness as I'm going crazy trying to figure it out!

nayr497

Thanks for your reply!

This last tube was right out of the Vredestein box, not positive when I ordered it, but within the last year and stored in a cool, dry closet. Mmm, this is a Ambrosio Excellight rim - 14.1/19.3 mm inner/outer width. Tire is a 25 mm Vittoria Corsa, which run on the bigger side for what they're marked. Tube is a Vredestein unpigmented latex tube, 23/25mm width. I ride on the rear around 100 psi, as I'm around 65 kilos.

OneIsAllYouNeed

Hmm. All of those measurements are well within the range of "normal".

Any broken threads/cords inside the tire?

What tools do you use to install the tires? (sounds like a box knife is involved -- just kidding)

Have you tried talc powder outside the tube?

After installing, do you inflate the tube to ~20psi, then empty, then pump to full pressure?

Have you tried mixing and matching with other tires or rims?

nayr497

I JUST SET UP SAME TIRES - VITTORIA CORSAS WITH VITTORIA TUBES - ON ANOTHER BIKE. NEXT STEP IS TO TRY A VITTORIA TUBE ON THIS PROBLEMATIC WHEEL. BUT AGAIN, I CAN'T SEE ANYTHING IN THE RIM OR TIRE, SO I'M QUITE CONFUSED WHAT IS CAUSING THE PUNCTURES.

Caps for ease of seeing, I'm not yelling at you

OneIsAllYouNeed

There was a thread on Slowtwitch regarding a similar latex tube issue. I think they concluded the tubes were manufactured poorly.
Latex Tube Failure Help: Triathlon Forum: Slowtwitch Forums

Personally, I've only used Vittoria and Challenge latex tubes (pink ones in all cases). All my flats on them have been easily explained.

velocentrik

Waiting for the phrase: "those are latex tube problems" to now be a thing in the bike mech forum. Just for grins, whenever someone humble brags about high end kit.

dabac

Inflate tube outside tire to about double size.
Does it swell evenly or with lumps and bumps?

A tube that looks like a recently fed snake will have uneven tube wall thickness and may well explain your problems.
I went through a bad batch of Geax tubes some years ago. When I cut one open the differences in wall thickness became obvious.

DannoXYZ 

Where do you start and end pushing the tyre onto rim?

nayr497

That slowtwitch discuss is a good one, mine have happened right at that same seam spot, so maybe I got a bad batch. But I've used Vredstein for years before with no issues. And I'm not sure I purchased all of these from the same supplier. Can't remember.

So I tossed in a Vittoria butyl tube, put in a ride yesterday. No issues, no punctures. Hmm, again seems to make it seem like a tube issue, not a wheel issue. Unless butyl is that much tougher and can deal with the rim issue.

DannoXYZ 

If you inflate a tube to double its size, the tube is being stretched a certain amount right? If you then stuff it into a vessel that constrains it to less than that stretched size, the tube is experiencing less stretching right?

Let me illustrate the differences in loading, you may want to follow along with a physical experiment.

1. take a Kleenex tissue paper and completely wet it. Carefully wrap it over the top of a bowl where it can cover top. Hold it where it wraps around edge. Place an orange or heavy object over the wet tissue. What happens?

2. take another Kleenex tissue paper and completely wet it. Lay it out on a tabletop. Place an orange or heavy object over the wet tissue. What happens?

nayr497

I generally insert the valve through the rim hole, set the tire at the valve, work around both directions at same time from there, wheel over my thighs, and then finish away from the valve hole.

You thinking I should finish at the valve?

DannoXYZ 

I'm saying that it is not coincidental that the failure occurred near where you start or end the tyre mounting. Try this slight modification to procedure:

1. do not install tube flat, pump in some air so that it is round in shape before inserting into wheel & tyre

2. mount tyre as usual

3. after tyre-mounted, push valve-stem into hole, so that it contacts tyre on opposite side internally

4. next, push edge of tyre sideways and look into gap between rim-edge and tyre. Move over 6-inches and push tyre aside and look at gap again, repeat 6-inches over. No tube should be visible all 360-degrees around wheel. Repeat for other side of tyre.

5. pump up to operating pressure.

6. install valve-stem nut if you wish, I prefer to leave them off.

DannoXYZ 

For the same weight and wall-thickness, latex is much tougher than butyl. That's why it can be made thinner and lighter. Personally I don't think there's really any benefits to latex given its higher leak-rate. I prefer to use thorn-resistant touring butyl tubes with Slime added. A single flat negates any possible benefits simply from extra time needed to fix that flat. And all extra time spent re-inflating self-leaking tubes.

What we really need is an automated pressure system related to TPMS sensors in autos. After inflating tube, attached CO2 cartridge to valve-stem and leave attached. Automated sensor bleeds air from cartridge into tyre to maintain desired pressure.

nayr497

So I think you're saying that by not seating the tube at the valve by pushing on it, I'm creating a recipe for a failure near the valve area? Seems like the most logical thing I've heard. Thanks.

DannoXYZ 

There are many areas where the tube can be pinched between rim & tyre. The valve-stem area is very prone to this due to thicker reinforcement that causes it to sit sideways and refuse to go into tyre when it's mounted. Pumping up tube first and pushing valve-stem into tyre both help reduces chances of pinching. Last final physical & visual check to confirm no pinching alleviates this problem completely.

nayr497

Hmm, but I do put a little air into the tube prior to installing into the tire. I also visually inspect them very diligently. These aren't from being pinched between the tire edge and rim, as I make sure the tube is entirely inside the tire casing.

DannoXYZ 

Hmmm, perhaps it's something with rim or tyre. Is hole in tube on rim-side or tyre-side of tube? Your measurement of 2cm seems to line up with a rim-hole. What type of rim and rim-strip used? Try pushing finger on rim-strip over hole, there should be no movement.

Slide your fingers all around inside of tyre and check for defects. Slide fingers all around inside of rim-flanges and along rim-strip. I've had issues with Velox tape rim-strips that were too wide for rim. Conversely had problems with strips too narrow and allowed tube to squeeze into rim-hole.

dabac

Well yeah. The extreme being a tube exactly as big, or bigger than the tire, that wouldn't have to stretch at all. In which case stretch would be an unlikely reason for tube failures.


And this would have to be actual size, not size designation.


OP does say :" Tire is a 25 mm Vittoria Corsa, which run on the bigger side for what they're marked. Tube is a Vredestein unpigmented latex tube, 23/25mm width"

If there is stretching - which seems reasonable according to above - a tube that's unevenly thick from fabrication will stretch at different rates depending on thickness.
Maybe enough to induce failure.


I've had that happen, so I'm suggesting a way to check for tube thickness consistency.

nayr497

I've really inspected the rim and tire as extensively as I can, and many times, as I've had like 10 punctures now. The rim tape seems to be the perfect width, not moving around, and the rim doesn't have any sharp edges. My only thought is the rim hole, but the punctures occur a few cm's away, so it seems unlikely the tube is going into the hole.

I guess the next diagnostic step should be to put in one of the Vittoria latex tubes I have and see what happens. Day two with the butyl tube in the wheel and no issues. And, rode my other bike, which has the Vittoria (instead of Vred) tubes, today. No issues.

I really inspect the heck out of the tubes upon installation, that is why I'm so confused by all the failures.

nayr497

Okay, so did some work on the issue over the weekend. Put a Vittoria red latex tube on the rear wheel, put in a ride, no issues, no punctures. I also pulled the front tube to put a bit of clear tape on the valve, as it was a bit narrow and would rattle in the rim. Been meaning to do it for awhile, finally got around to it. I carefully installed, inflated, left overnight...woke up Sunday morning to a front flat.

You guess it, right at the seam, a few cms from the valve. I think I'm going to give up on Vredestein and see if I can continue the good luck I've had so far with the Vittoria. Have them in both wheels on one bike, just the rear on the problematic bike, as I need to order more tubes. Still not positive what it is, but those wheels and Vredestein tubes do not match.

trailangel

nayr497

Alright, but I've had so many tubes flat at this point that I know they're not all from the same order/supplier. Seems unlikely that 10+ tubes would all be really old, doesn't it?