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General Category => General Discussion => Topic started by: Enrico Pallazzo on February 03, 2015, 02:49:57 PM

Title: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 03, 2015, 02:49:57 PM
Wondering if people could give me some info on pinched inner tubes.

I got a screw in the rear tire on my Softail the other day. It leaked slowly, so I was able to pump it up and ride it to a shop. They put in a new tube. Then over the weekend, I rode to Key Largo and back. On the way back, about three miles from the house, I noticed the steering was wobbly. I pulled into a gas station, and sure enough, the tire was going down again. I managed to get home at 20 mph.

When I pumped the tire up to 40 psi, the air really flew out of it. I couldn't find a nail or screw. The air really rushed out, as if the leak got worse while I was limping home. Now I can't even make it out of the driveway.

I am thinking the tech pinched the new tube somehow while installing it. I am waiting for the shop to call back. But this got me wondering: is a really fast leak generally indicative of a pinched tube? Also, is it normal for this kind of leak to get worse while you ride?

My Jackal has tubes, too, so whatever I learn will apply to it.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: cruzziguzzi on February 03, 2015, 02:59:10 PM
Don't know where you live but "... Key Largo and back" is far enough to give pause as to a pinched tube. Coulda ran over something for a puncture and the entry hole is scuffed over sufficiently as to hide it. Pinched tubes (my fault) usually have exhibited their presence almost immediately.

Todd.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: rodekyll on February 03, 2015, 03:01:06 PM
It could be the tube snout wasn't properly installed and got abraded or cut.  This mystery will be solved when you pull the tube back out.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 03, 2015, 03:02:27 PM
Key Largo is not far from here. The ride was a little over a hundred miles, total.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: redrider90 on February 03, 2015, 03:11:07 PM
My dime is on they left something inside that is caught between the tube and the tire. Most like a very small item even a very small stone or even the washer that goes between the valve stem and the rim.
I did that very thing. The washer unbeknown to me slipped out of my fingers and landed between the tube and the tire. After 15 miles I lost all air fast. The vibrations wore a hole in the tube from the washer. What makes me think it is something smaller is that you got 100 miles before you lost air.  I think a pinched tube would have revealed itself sooner rather than later. But I suggest you be "bedside" when they pull the tube and have a good look see inside the tire.
Heck it may also be the rubber guard that protects the rim/spokes from the tube is out of place ever so slightly.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 03, 2015, 03:14:41 PM
They are going to cover it if it's their fault, but to find out, I have to bet them a $50 trailering fee. Not sure if they'll eat that or not.

It would be a hell of a coincidence to get rear-tire flats on two rides in a row, on different roads.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: rodekyll on February 03, 2015, 03:33:22 PM
I rode along with a woman on some Honda a few years back.  She got three nails in her tires -- two front and one rear -- in one day's riding, some hundred miles apart, on the same road.  It was a bad day for everything except the slime compressor.  That little turd performed as advertised.  When we parted ways a couple days later I gave her my patch kit (but not the compressor).
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: charlie b on February 03, 2015, 03:58:08 PM
RK may be right too, if the tube wasn't positioned well then it could also be the stem cut through.

On previous bike I pinched tubes all the time.  Showed up immediately.

If it isn't something picked up on the road I'd bet on something left in the tire.  A tech here let that little washer get between tube and tire on one of mine.  Went a few hundred miles before it wore through.  Slime and a compressor (also slime) got me home that time.

After that I converted my rims to tubeless  :D
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 03, 2015, 04:21:25 PM
I am not in love with the tubeless rims. I didn't know the Harley rims were made that way. Not a big surprise on the Jackal, for $7000, but the Harley cost a little more than that.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Sasquatch Jim on February 03, 2015, 07:12:46 PM
  Flat tires happen to all of us.  The only way to know what caused it is to take it apart.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: LaMojo on February 03, 2015, 08:06:02 PM
Maybe that Chinese tube split at a seam.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: LaMojo on February 03, 2015, 08:07:40 PM
Maybe that Chinese tube split at a seam.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: 1Sourdough on February 03, 2015, 08:35:16 PM
I had a flat one fine day, about half a mile from a garage.  Folks there pulled the tire and patched the tube.  Thirty some miles back to Elkader, and a little while after arriving the tire was visibly low.  Enthusiasts had the tube out and replaced in just a few minutes, and I left again.  Tire went flat a third time.  We arranged to trailer it home while I rode the Good Samaritan's Guzzi.  Wheel off the machine and to a local tire shop, where a tiny, perhaps 1/32nd or 3/64th inch grain of gravel was found inside the tire.  It doesn't have to be a big hole, doncha know!
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Petrus Rocks on February 03, 2015, 10:19:12 PM
Another thing to check is the valve core.  Sometimes the core isn't tightened completely and will slowly leak.  This could cause the slow leak you describe.
My experience has also been if you pinch the tube it deflates pretty quickly.  I have had to run my fingers carefully around the inside of a tire to find a puncture problem as well.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: SED on February 03, 2015, 10:34:15 PM
I'd bet the reason it's leaking faster now than on your ride is that the low tire pressure let the tube slide inside the tire and pull the valve stem partly out of the tube = fast leak.

Why the new tube went low during your ride is hard to know, but on my bicycles it's usually when the initial puncture is due to broken glass and a little shard remains in the casing.  It cuts through the tube after a few miles becoming a slow leak that gets faster with distance. 
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 04, 2015, 09:52:58 AM
The shop is sending a trailer today. They proposed the same solution I was going to: if they screwed up, they pay for everything, including picking up the bike. If not, I pay. Good enough for me.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 04, 2015, 10:30:21 AM
Here's a question I should have asked: how do you prepare for tube-tire flats? I can't use plugs while I'm on the road, so what's the answer?
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 04, 2015, 10:45:41 AM
Sounds like I'm screwed. I mean, there is no way I can get the tire off a Harley on the side of a road, with no lift and no tools to speak of. Especially the back tire.

So there is nothing I can shoot in through the valve, like Fix-a-flat?
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: LowRyter on February 04, 2015, 10:57:43 AM
I am not in love with the tubeless rims. I didn't know the Harley rims were made that way. Not a big surprise on the Jackal, for $7000, but the Harley cost a little more than that.

why not?  Tubeless + Patch kit would've saved lots of grief. 
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: LowRyter on February 04, 2015, 10:59:10 AM
Here's a question I should have asked: how do you prepare for tube-tire flats? I can't use plugs while I'm on the road, so what's the answer?

see above.

best answer is tubeless rims
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 04, 2015, 11:00:05 AM
Meant to say I was not in love with tubes.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: HDGoose on February 05, 2015, 07:52:44 PM
They are going to cover it if it's their fault, but to find out, I have to bet them a $50 trailering fee. Not sure if they'll eat that or not.

It would be a hell of a coincidence to get rear-tire flats on two rides in a row, on different roads.

Cue Hagan....
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 06, 2015, 05:53:36 PM
The shop called. The tube failed at the base of the stem. They're paying!
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: oldbike54 on February 06, 2015, 05:55:59 PM
Cool  ;-T

  Dusty
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 06, 2015, 06:04:51 PM
Yeah, that was a hundred bucks I didn't feel like paying twice.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: redrider90 on February 06, 2015, 07:56:53 PM
The shop called. The tube failed at the base of the stem. They're paying!


Why did it fail at the base of the stem? Did they fail to put in the washer? How else would it have failed?
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: rodekyll on February 06, 2015, 08:33:47 PM
If the washer was missing or the stem wasn't properly nutted down, yes.  Also, if the snout wasn't centered properly it can rub on the rim hole.  If the rim wasn't cleared of rust and scale around the rim hole (where rust often starts) it can abrade.  If the tire spun on the rim it can shear the stem.  That's why we have rim locks on dirt bikes.

But the shop decided either that it was a bad installation, or that they wanted to extend good will to the customer.  Either way, they took responsibility.  That's a good thing.   ;-T
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: johnr on February 06, 2015, 09:06:22 PM
Tire spoons , a patch kit or spare tube , and some inflation method .

  Dusty

I like a push bike patch kit better than a spare tube. Much smaller to carry and will deal with more than one puncture.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Triple Jim on February 06, 2015, 09:26:11 PM


Yeah , just make sure that your tubes will "take" a patch . Some modern tubes will not hold a patch . Don't ask how I know  ::)

  Dusty

No insult meant, Dusty, but the only time I've had a tube not take a patch was when I didn't scuff it up enough.  Are you sure you used something like sandpaper to get down to matte black rubber?
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: johnr on February 06, 2015, 09:35:42 PM
Sounds like I'm screwed. I mean, there is no way I can get the tire off a Harley on the side of a road, with no lift and no tools to speak of. Especially the back tire.

So there is nothing I can shoot in through the valve, like Fix-a-flat?

Well carrying the tools to get a wheel off is a given need, find a way. Push bike tyre spoons are easiest to use and small to carry, but make sure you have three of them.

On my BSA R3 I used a a pump that worked off one of the cylinders by replacing a spark plug with it (I had shortened it and deleted it's gauge to keep it packed small)  They work on twins too but I'm not sure about injected bikes as I think you would get a fuel mix in the tube with them.

If you haven't got one how about a center stand? (Otherwise you will have to lay the bike on it's side.

If neither of those is in fact practical I would be looking for another bike in reality, as that one is obviously not meant to venture out of town. (away from a bike shop)

I too am not sold on tubeless tyres though that is what I have now. To date I've found that a puncture on a tube tyre was a pain in the proverbial and the cause of the emission of a number of expletives, not to mention dirty hands, but an easy enough process to carry out. The one time I tried it I was unable to actually use a tubeless tyre kit, and tyre changing is far harder.

Though I have used one successfully, the trouble with 'Tyre Pando' and such products that you simply inject through the valve is that they only really work on holes that are on the outside of the tube, where most, but not all of them, occur. It can be much harder to find the cause of the flat sometimes as it may not protrude out of the outside of the tyre and you don't get the opportunity to feel around for it. It will also lift off any patches that are already there.

At the end of the day I absolutely refuse to be stranded in the middle of nowhere, and no doubt out of cell phone coverage, by something as simple, common and easy to fix as a puncture. I'ts going to cost me some dosh to get the needful gear for tubeless tyres, but so must it be.

Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: lucky phil on February 06, 2015, 11:46:39 PM
You'd know the reason by now if you went out and pulled the wheel and tire instead of postulating about it on the internet.

Ciao
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: rodekyll on February 06, 2015, 11:57:27 PM
Where's the fun in that?
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: NorthRider on February 07, 2015, 06:56:55 AM
I really like the tubeless tire design.
Once on a trip around Lake Superior, buddy of mine punctured his rear tire with what turned out to be a piece of bone. We only noticed it once at the hotel.
So out came my tire plug kit and pump. In less than 30 minutes, I had the tire plug in place, and tire pimped back up. Minimal mess and stress!
That fix not only lasted the rest of the trip, but the guy ran that plunged tire for the rest of the summer.
I don't think I would go back to tubes for a touring bike ever.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: biking sailor on February 07, 2015, 08:43:43 AM
For me, road bikes used for touring will have a centerstand and tubeless tires.  And I carry a slime pump and plug kits.  Have had to use them several times, but never on my own bike???  May of just jinxed myself, but it is a weird phemon.  I've found nails in tubeless tires found after I got home, though.

I do always try to ride in tire paths and not down the center of the lane or get to close to the center of edge, even when carving curves hitting apexes (that's saved for the track days that are now well in the past). 

I've pinched quite a few tubes during tire changes and a several times riding off road when the tires are aired down and landing hard on rocks.  Have had to lay the bike on it's side more than once to get the wheel off.
Title: Re: Pinched Tube Behavior - NGC - Harley
Post by: Enrico Pallazzo on February 07, 2015, 09:29:08 AM
You'd know the reason by now if you went out and pulled the wheel and tire instead of postulating about it on the internet.

Ciao

I didn't pay these guys good money so I could do their work.

I know what's wrong with the tire. Like I said, the shop called.