Tyre issue

[cwah]

Hello,

I have been trying to change my spokes, and put the tube back to the wheel then pump it. It's a marathon plus tyre so it should accept very high psi. (80+). But once I pumped it high to 85psi, it just exploded close to the valve.

I purchased new tubes:
http://www.amazon.co.uk/gp/product/B00DCYNPWQ?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00

And now I've tried it again on my tyre and I've noticed a bump next to the valve:

Everything seems ok, the tube is not going over the tyre.... but is it normal?

 

[D8ve]

That's bad news, the beading that links into the rim is about to become detached and you hear a LOUD noise.

 

[cwah]

Is it an issue with the tyre?

I have moved the tyre around and it only show that on the valve area. Tyre seems ok

 

[Deleted member 4366]

I had exactly the same. I believe that my one had been on and off the wheel a couple of times. I suspect that someone stretched the rim wire by incorrect use og tyre levers - trying to lever it over the rim without getting the bead into the well of the rim. Mine blew off the rim twice while I was riding it.

You have to chuck it away and get a new one.

 

[cwah]

I'm removing the tyre like this:

Is it incorrect? Also, moving the tyre around doesn't make a difference

 

[D8ve]

It could be damage to the rim?
Is the indent that the bead seats in damaged at all?
As there is significant pressure any deformation could cause the slip

 

[cwah]

If it's rim bead/wire damage, this bump should be visible when I move the tyre around. But it is only present next to the valve.

Isn't it something to do with the rim or something else?

 

[cwah]

Rim seems normal

 

[D8ve]

You were thinking the same as me.
Best go see a shrink then ;-)

 

[cwah]

see a shrink??

 

[D8ve]

Self depreciating humour. Shrink, head doctor. Suggesting that anyone who thinks like me is mad ergo I'm mad. Even though we were agreeing on most likely cause of your problems.
The rim would only need slight weakness or damage?

 

[JamesW]

It's not the rim tape pushing the valve up and into the tyre where the valve goes through is it? If the inner tube is not seated perfectly, a pinch will be more noticable at higher pressure. ( got caught out by that myself a few times before.)

 

[DannyK]

I have the same thing on my Woosh and I think it is because I bought shorter stemmed valves and the tyer can't sit down enough in the rim as the inner tube is holding it out.

 

[grldtnr]

It's not the rim tape pushing the valve up and into the tyre where the valve goes through is it? If the inner tube is not seated perfectly, a pinch will be more noticable at higher pressure. ( got caught out by that myself a few times before.)

I reckon I know the problem .the valve stem is not seated right, what you need to do is put the tyre on correctly, I shall now teach you to suck eggs!
1.assemble tyre and tube on the rim, make sure the rim tape is snug in the rim well, with no kinks ,twist or edges, there normally are an inside and a outside to the rim tape, make sure the smooth outside is uppermost.
2.with the valve stem in the valve hole, without the lock nut on. partially inflate tube so it holds shape, tuck in tube to tyre.
3.mount the tyre to the rim, starting opposite the valve, do this by using your thumbs, push the tyre into the rim by sliding your thumbs along the tyre wall ,one hand in each direction , from bottom to top at the same time, sometimes this can get tight as you get to the valve hole,refrain from using levers to fit tyre.
4. pump up tyre, till it is hard, not full p.s.i., this will seat tube into the rim.
5.here is what most people fail to do! let the tyre down flat ,push the valve in but not so far that you lose it, run your hands around the tyre/ rim using a pinching of thumb & fore finger, this will seat tyre properly,
6. now pull the valve fully home, put the lock ring on the valve, pump the tyre to full pressure in the bike.

doing it this way ensures the tyre bead sits correctly, the valve mounting can not get in the way of the tyre beading, it sits above the beadings.

I stress that you should not need a tyre lever to put a tyre on, sometimes getting the tyre back on for the last bit is difficult, if so peel the tyre of and use some talcum powder to help ease it on

of course should the tyre still not fit ,it needs junking

 

[Gringo]

Without being there it looks like the tyre rim is sitting on top of the tube around the valve.
When I've had a tube trapped like that, I've let all the air out and removed the valve locknut and pushed the valve stem back into the rim ( not so far as it won't come back)
If the tyre rim is trapping the tube it will be hard to push, if the tube is clear of the rim them it should only take a little pressure and feal a bit springy.

For every tyre I fit I always have the tyre rim seated around the valve area first, it's only when I've worked the tyre almost entirely onto the rim that I need leavers and by that time I'm on th opposite side to the valve.

 

[Gringo]

I Stress that you should not need a tyre lever to put a tyre on

Your a hero, remind me never to shake you by the hand.

I've been changing tyres on all types of pushbikes & motorcycles for over 40 years and I'd never surgest people don't need tyre leavers.
Yes it can be done on some tyres and it helps if you have big strong man hands.
These days my arthritis would be a problem without mechanical assistants.

 

[Deleted member 4366]

I have arthritis as well, but I can always put a tyre on with nothing more than bare hands. It's simply a matter of technique.

You never need levers to get the first side on (do you?). Therefore, you don't need them to get the second side on.

 

[selrahc1992]

Your a hero, remind me never to shake you by the hand.

I've been changing tyres on all types of pushbikes & motorcycles for over 40 years and I'd never surgest people don't need tyre leavers.
Yes it can be done on some tyres and it helps if you have big strong man hands.
These days my arthritis would be a problem without mechanical assistants.

apologies for stating the very obvious, but the "well" in the rim is the key, squeeze the wire of the tyre on the opposite side completely into the deepest bit of the well and even a complete weed like me can squeeze a marathon plus on

 

[mike killay]

Cwah,
It can help if you put some liquid soap around the inner tube by the valve.
I have had this problem and it is caused by the valve seat. What I mean by this is that where the valve joins the inner tube the rubber is thicker, a harder round circle of rubber. If this circle is too big, it has trouble slipping completely inside the tyre so that when you pump it up, the tyre is standing on the harder circle of rubber.
It may help if you put one side of the tyre on first, slightly inflate the inner tube and put the other side of the tyre on first at the valve. This will allow you to check that the circle around the valve is inside the tyre completely. Then deflate the tube and finish putting the tyre on.
Bike mechanics will hate this as they are always taught to put the valve part of the tyre on last and push the valve in to ensure that the circle is inside the tyre. Sometimes however, this does not work.

 

[cwah]

I wasn't sure what would be the issue but the rim tape may have been the trouble maker.

I decided to completely remove the rim tape and pump air directly on it... and it works!!

I'm going to make a bigger hole on the rim tape and follow all your instructions and gnrtlr ones

Thank you guys


ps: I never managed to remove marathon plus tyre without lever. They are extremely hard tyres. Not sure if any technique works with them. I can however put them back without tools