Innertube leaking at the base of the stem, how to avoid this in the future?

[David Robert]

Good afternoon, first post, I don’t know whether I should’ve put it here or in the safety riding section.  Short version is, my innertube is leaking the base of the valve stem.  I’ve already ordered a replacement, but I’m wondering if I’m just unlucky, or there’s something I could do to avoid ruining another innertube valve stem.

I don’t ride on rough terrain and I don’t remember hitting any curbs.  I avoid potholes, go slow over speed bumps, etc.  but I’m just wondering anything while riding that could cause my problem so I could avoid it happening again.

Thank you.

 

[Paradox]

Make sure the tube is inflated to the correct psi. An underinflated inflated tube can shift inside the tire and rip at the valve stem since it can not shift.  A properly inflated tube also helps to keep the tire from slipping on the rim which could also shear the valve stem off. There might be other precautions to take too.  Let others chime in.

Edited October 23 by Paradox

[David Robert]

Appreciate you

46 minutes ago, Paradox said:

Make sure the tube is inflated to the correct psi. An underinflated inflated tube can shift inside the tire and rip at the valve stem since it can not shift.  There might be other precautions to take too.  Let others chime in.

 

[Funky]

Check if rim hole doesn't have sharp edge.. I had same issue 2 times.. One time stem got ripped off.. Other time cut right where stem meets the tube.

I took sandpaper and sanded down the rim hole little bit down - making it more round edged. Cone like - so tire/stem could sit more gently in the rim hole.

 

I also took old tube and cut round patch and added extra layer around stem of the new tube - more robust. (Put little hole in middle of patch, put it over stem and glued it onto.) 

I ripped my stem 200km apart of each time it happened.. First time - i was okay.. That happened. Second time 200km latter it happened again and i was angry, so i took extra steps to not let it happened again..

Edited October 23 by Funky

[Hellkitten]

When you change your tube, check the valve stem hole in the rim for sharp or rough edges. File or sand them them smooth if you find any. Make sure your tire is at a decent pressure, as paradox mentioned. 
Which wheel is this BTW? Some models seemingly have more failures at the valve stem then others. 
you should also be fine hitting speed bumps and that kind of thing without ripping your stem. It’s something else. 

[David Robert]

2 hours ago, Hellkitten said:

When you change your tube, check the valve stem hole in the rim for sharp or rough edges. File or sand them them smooth if you find any. Make sure your tire is at a decent pressure, as paradox mentioned. 
Which wheel is this BTW? Some models seemingly have more failures at the valve stem then others. 
you should also be fine hitting speed bumps and that kind of thing without ripping your stem. It’s something else. 

Inmotion, V10F

[David Robert]

3 hours ago, Paradox said:

Make sure the tube is inflated to the correct psi. An underinflated inflated tube can shift inside the tire and rip at the valve stem since it can not shift.  A properly inflated tube also helps to keep the tire from slipping on the rim which could also shear the valve stem off. There might be other precautions to take too.  Let others chime in.

I remember that it had been a week or two since I last inflated the tire at a local gas station.  I probably ran it too low for too long and that’s exactly what happened.  I just Invested in a portable air compressor to make sure it never happens again.

[alcatraz]

Don't use soap on the rim edges when mounting the tire. You might in fact want to clean the rim edges and the tire beads with alcohol so they lock in place better. 

Also if you use plenty of talcum powder inside the tire, on the tube, it seats way better avoiding lots of tear related damage.

[Jmac]

10 hours ago, David Robert said:

Appreciate you

 

This is my thought too. It's actually the inner tube pressure which forces the bead of the tire onto the metal. It's totally a friction connection. Reduce the pressure and the rubber tire has some freedom to slide on the metal rim, carrying the inner tube with it. I suffered a series of problems with a bike once I never could figure out. Ultimately, I put a layer of contact cement on the metal and that seemed to stop it after a number of tubes failed at the stem. 

Nice nice! Thought to make sure there's no sharp edges, but fact is the stem should not be absorbing the shear resistance of a a tire sliding ever so slightly on the rim.

I think this might speak to those who like to reduce tire pressure in certain situations. I wonder what it feels like to walk in EV with a flat tire, a few miles of backwoods trail

[Funky]

9 hours ago, alcatraz said:

Don't use soap on the rim edges when mounting the tire. You might in fact want to clean the rim edges and the tire beads with alcohol so they lock in place better. 

Also if you use plenty of talcum powder inside the tire, on the tube, it seats way better avoiding lots of tear related damage.

Soap - Don't

Soapy water - It's best method to mount these hard M/C tires.

Old flimsy CST bicycle tires could be mounted easily by hand, no need for tools or anything.

I used sandpaper to "rough" up the rim and tire bead.. By not being completely smooth - they can't slip that easily. Also when i removed tire - it's bead was SO shinny and slick from being om rim... You could see that tire was moving little bit while riding. As tire bead was polished.

7 hours ago, Jmac said:

I wonder what it feels like to walk in EV with a flat tire, a few miles of backwoods trail

Luckily for me - both times happened right next to my house. Trolley up and pushed it home - same as with full tire. No difference.   (It's good to have those M/C tires - they keep the shape even when being completely without air.)

[alcatraz]

1 hour ago, Funky said:

I used sandpaper to "rough" up the rim and tire bead

That's interesting.

[on one]

22 hours ago, David Robert said:

I’m wondering if I’m just unlucky, or there’s something I could do to avoid ruining another innertube valve stem.

I think this is just the spot where the tube usually wears out. When I bought my King Song 14D on Ebay I think the valve stem was wearing out because I had to install a new tube within like 4 months which is sort of a difficult job. That's probably why they were selling it.

[onewheelkoregro]

@David Robertdid you resolve your valve stem issue? I ask because I am experiencing the same issue on my Commander Pro. I have gone through 3 tubes in October alone. I got my cpro in April of 2024 and the valve kept getting sucked in so I increased psi in my tube and it mitigated it for a little bit but then it ripped a small hole by where the valve meets rubber. The second tube failed in the exact same spot in the same way. This third tube completely separated from the valve and I am looking for a solution as well. So can you please share which of these methods alleviated your problem for you?

Just to add a quick note the 1st tube replacement I just put in normally. The latest one that failed in not even one whole commute I baby powdered the tube to help it sit correctly

[alcatraz]

On 10/27/2024 at 1:01 AM, onewheelkoregro said:

@David Robertdid you resolve your valve stem issue? I ask because I am experiencing the same issue on my Commander Pro. I have gone through 3 tubes in October alone. I got my cpro in April of 2024 and the valve kept getting sucked in so I increased psi in my tube and it mitigated it for a little bit but then it ripped a small hole by where the valve meets rubber. The second tube failed in the exact same spot in the same way. This third tube completely separated from the valve and I am looking for a solution as well. So can you please share which of these methods alleviated your problem for you?

Just to add a quick note the 1st tube replacement I just put in normally. The latest one that failed in not even one whole commute I baby powdered the tube to help it sit correctly

I'd work on the tire/rim interface. Try cleaning the bead+rim. Possibly even lightly sand the rim on the inside with some emery cloth. 

Another thing to note is which side of the valve is it that tears? The side that is stressed under hard braking or hard acceleration?

Another issue could be that the inner tube isn't big enough for that tire. It gets stretched out too much.

Also, try a decent brand inner tube like cst. Check for sharp edges.

Edited October 28 by alcatraz

[onewheelkoregro]

12 hours ago, alcatraz said:

I'd work on the tire/rim interface. Try cleaning the bead+rim. Possibly even lightly sand the rim on the inside with some emery cloth. 

Another thing to note is which side of the valve is it that tears? The side that is stressed under hard braking or hard acceleration?

Another issue could be that the inner tube isn't big enough for that tire. It gets stretched out too much.

Also, try a decent brand inner tube like cst. Check for sharp edges.

I think I am going to try applying epoxy on the rim where the tire bead sits and while the epoxy is still wet putting fine sand in it. The issue is the tire slipping. The first two were while braking and this one was accelerating uphill. So when the new tubes come in that's what I am going to do to my rim and then I will cut a piece of the old tube and put it over the new valve stem and glue it directly to the tube and the valve stem

[on one]

Our wonderful friends at ewheels sent me a quite robust replacement for my tube, the part of the tube where the valve sealed to the tube was like 10x as thick as  the original tube. I only wish King Song had provided me with a robust tube in the first place since it was really difficult to replace. Why can't we have a wheel manufacturer who actually looks out for their customers actual enjoyment and longevity. Other than the tube, my King Song 14D has been a very great wheel and is my favorite one so far compared to Ninebot Z10 (also a lot of fun when mastered and extremely robust) and my V10F which was a lot of fun too, but it broke on me after like 6 months because it got dented rims too  easy and did the death shake, and it got all chipped and scratched up too easily. Inmotion sucks.

Edited October 28 by on one
typo

[alcatraz]

On 10/28/2024 at 10:18 PM, onewheelkoregro said:

I think I am going to try applying epoxy on the rim where the tire bead sits and while the epoxy is still wet putting fine sand in it. The issue is the tire slipping. The first two were while braking and this one was accelerating uphill. So when the new tubes come in that's what I am going to do to my rim and then I will cut a piece of the old tube and put it over the new valve stem and glue it directly to the tube and the valve stem

That's interesting. Thermal expansion and contraction is eventually going to break a bond but if you pick a good one that remains a bit sticky it could last a longer time.

The tire is probably not the best fit for that rim. You might not need to do anything if you pick a different one. I know though that once we have a favorite we tend to stick with it, no pun intended.

[onewheelkoregro]

9 hours ago, alcatraz said:

That's interesting. Thermal expansion and contraction is eventually going to break a bond but if you pick a good one that remains a bit sticky it could last a longer time.

The tire is probably not the best fit for that rim. You might not need to do anything if you pick a different one. I know though that once we have a favorite we tend to stick with it, no pun intended.

The only other so!Union is to silicone either one side of the tire to the rim or both. But that sounds like a nightmare tire change. Some guy had the same issue and he did something similar

 

[Bizra6ot]

You can also install single or dual rim locks https://www.rockymountainatvmc.com/tires-and-wheels/tusk-motorcycle-rim-lock-p

[drader]

We ride a small tire with tons of torque - the tire is slipping on the rim, and yanking the tube with it. I have been using gasket-maker silicone to glue the tire to the rim. This easily pulls off, but seems to have done the trick. Prior to this I've had 4 flats: one was a snake bite from low inflation; the other three were yanked valve stems. I don't get flats anymore.