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giant tubes


badchef's picture

By badchef - Posted on 03 April 2014

NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.

Recently purchased a 27.5 tube and put it in my rear tyre,pumped it up to 40 psi,seated properly with no abnormalities,left it at 40 psi and it blew up overnight,tyre is fine,tube is a right off,,tyre is rated to 50 psi,and rim rated to 3 bar,has anyone else had problems with giant tubes?

[Mod. moved to MTB gear]

Zoom's picture

The problem will be due to a spoke hole not covered with rim tape or the rim tape is not thick enough, or maybe a rough spot in the rim. It's probably not due to a tube manufacturing fault. What caused the previous tube to fail?

badchef's picture

Previous tube pinched due to a one footed(see clipped out) huck to flat,striking my rear tyre on a rock,snake bite,the rimstrip looked fine,rim is perfect too,bike is 2 hrs old,tube said it is .73 mm thick,too thin maybe?

Flynny's picture

Did you make sure the tyre beaded properly as you blew it up?

If the bed was a little out as you pump it up it will work it's way off and the tube will pop out the gap

tdunster's picture

Pump a tube up inside a tyre and it can get to 65psi or more without any problems.

Pump a tube up that's not inside a tyre and it will pop well before you get to 65psi.

In your case the bead is not sealing correctly and as a result the air outside the tyre is causing the tube to pop just like it would when it's not inside the tire.

If it were a rim tape / spoke problem you would usually have a slow leak.

When it is a case of the bead not sealing correctly the tube will go out with a bang.

Solution: New Tyre because the bead on yours is no good.

CyclinAl's picture

I had the exact same problem with a condom some years ago. No damage to the "Tyre" thank goodness! (Yeah, I know. This one's a bit gross...) Evil
Jokes aside, what size were the tube and tyre? Not the wheel size but the bead-to-bead/width, whatever you want to call it size.
I'm asking because I found the pre "slimed" tubes to be of limited effectiveness when fitted in tyres that were at the high end of the tube sizing. I think the reason is that when you blow it up, by the time the tube actually makes contact with the inside of the tyre, it has already stretched to such an extent that the slightest aggression by a thorn or a sharp bit of rim, and undoubtedly any defect in the tube wall, leads the puncture to tear up rather than simply leak. In my case, the "slime" didn't help at all even though the punctures were caused by Double-Gs, which only make small pin holes.
So I would say, if your tube was used at the high end of the its size range, anything could have caused it to blow, including wall defect, which can't be discounted whatever the manufacturer may claim...

hawkeye's picture

Get a Stans or (better) a Bontrager conversion kit and go tubeless. Smiling

VTSS350's picture

Totally agree with hawkeye.

Tubes are a thing of the past!!!!

CyclinAl's picture

Absolutely, but there are times where using a tube is more practical, like when you want to fit different tyres for a single "event" (Might just be one day ride on a different surface) and it's not worth fart-arsing around with tubeless and wasting solution. I do it every now and then.
Badchef, any info on the sizing?

badchef's picture

Swalbe tyres,rock razors 2.35, the tube was giant 27.5 1.9-2.35 I think,as far as I could tell the bead was spot on,took it for a razz down the street checked it again ,it was fine,somehow I guess the tube made its way past the bead,expanded til kaboom,oh well,the maxxis tube is holding up ok,will stick to em

hawkeye's picture

I just recently swapped the rubber over on my Scalpel on Friday with a couple of new tyres and it was just as easy as using tubes:

1 Remove old tyre, hang on garage door knob.
2 Fit one side of new tyre
3 Tip sealant from old tyre to new, add a little more if needed
4 Fit other bead
5 Inflate with track pump until both beads seat fully
6 Go ride

Truly, it took less time than fussing about with a tubed tyre. I'm using Stans rims which do make life much easier but still there's no rocket surgery involved. Smiling

Last time I used a tubes setup was when I got my then-new Rize and couldn't wait for the Stans kit to arrive. Took it for a blat around Manly Dam... and got a pinch flat first lap on the second Creek crossing. Duh.

CyclinAl's picture

Could you please be more specific with the changeover procedure, especially the "Tip sealant from old tyre to new" without the bloody bead going Flip! and sealant flying all over the show?
Regarding your pinch flat around Manly Dam, you're being unfair, blaming the hardware when poor riding skills was probably the cause of the mishap! I mean, a simple creek crossing? Come on!
...
And YES! I am pulling your leg Smiling

VTSS350's picture

I agree its actually very easy to swap sealant from one tyre to the next.

I have a syringe that holds 100mm of fluid. I just suck the sealant out and squeeze it into the new tyre.

CyclinAl's picture

That's a good one VTSS350. Thanks for the tip.
I couldn't be without tubeless as a basic setup but these short tyre changes always have me balking at the mess of the sealant sloshing everywhere. But this really is a simple and effective solution.
Note to Hawkeye: "Include syringe in sealant transfer procedure... and a blindfold!" Eye-wink
Sorry Bad chef, sounds like I've just deserted the tube brigade definitively. Perhaps you should too...

hawkeye's picture

No way. I just used bullet time to catch all the drops before they landed.

CyclinAl's picture

Ok, then how do you suck up the latex "meteorite" that has formed inside your old tyre?

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