Help with tires - can someone show me how it's done?

[Ugo51]

Re:

Thanks guys.

I will try again tonight. If I feel brave enough I will take the tire off and try to put it on again.

Just so! Any tyres that are 1 hour jobs "at home" are to be avoided - will be impossible with cold, wet, hands in the dark by the road side!

I agree! But is the process of finding easy to fit tires entirely random? It's a pretty expensive hobby to keep o buying tires until one that fits comes up ... although, in the grand scheme of things, probably not so much

 

[2manyoranges]

Re:

No it’s not a new thing - not connected with tubeless - but actually things have got better in recent years with better QC in manufacturing and CE standards. There used to be terrible rim combinations - I remember some Mavics with Conti tyres were hideously tight. And the other way too - a Ritchey tyre so loose on a rim that is was like a banana skin draped over a glass and exploded off the rim at 30lbs inflation - Gapow!!!

 

[Ugo51]

Re:



You see, now the problem seems to be that the bead of the tire stays in the well of the rim instead of sitting where it should. I thought it was a problem of the rim tape, and I changed it for a thinner one, but the problem still persists...
You can see that the S of the word Specialized is still fully outiside of the rim but it progressively sinks in going onto the right.
What would cause the issue?

 

[2manyoranges]

Re:

Hmmmmm that's a bad case.

OK - three things

ONE
Check the ERTO of the tyre and the rim. There are many many sizes, far more than people think. Those Boardman rims can be a weird ERTO. Here is a very good source. If the ERTO of the tyre and the rim are the same, then it will be a case of fettling. If they are different you are DOOMED.

TWO
If the ERTO is the same, you are still not out of the woods. I love some Spesh tyres. But some are not good, too much inaccuracy on diameter and I swear some are a different ERTO to the figure given on the tyre. If the ERTO is the same, then you will need to pop the tyre onto the rim. Best with a track pump pumped swiftly, with Schwalbe mounting fluid or soap solution all the way around the rim. You can use baby talc too - which is good for stopping the inner weld itself onto the rim tape and tyre.

THREE
This looks like a terrible rim-tyre combination and I would not want to get a puncture out there on the road. Switch to Schwalbe or Michelin and see what you have.

 

[Ugo51]

I can easily measure the rim, but the tire?? Is a foldable one, hard to get an accurate measure...

I'll try popping it at high pressure. I need to go to the local bike shop tomorrow for that though, I only have a handpump that allows me 2-3bar at best

 

[2manyoranges]

You don't need to measure it. The ERTO will be on the tyre, and should be on the rim too, in tiny numbers on the rim label or somewhere. Should be 700 on both. I assume that they are 700 rims. Note that many people have TERRIBLE trouble with 24 inch tyres not knowing that there are two different ERTOs....both labelled 24 but different.

And note the max pressure that your rims can take. Sometimes you need to pump them to the max pressure, with soapy water all the way around, and then they go pop onto the rim and sit correctly. But that will mean over 100psi in that tyre of tyre I think, as long as that within the safety figures for the rim and tyre.

And actually it's almost impossible to measure the ERTO of a rim, since it is the circumference of the BEAD area not the top of the rim.

 

[Ugo51]

And actually it's almost impossible to measure the ERTO of a rim, since it is the circumference of the BEAD area not the top of the rim.

Yes, I was going to measure the top of the rim and then subtract the depth of the drop to the bead, but I would need to take the tire off for that

They are both 700c, so 622.
The tire is 622x25c
I haven't measured the rim width yet, but looks pretty narrow, probably 18mm (inner).

 

[Woz]

Recently wrestled with this.....with a 10 year old Schwalbe fold up on a Crossmax. My advice:

- leave the initial struggle on the rim (when you've already broke three tyre levers!), and ....
- put a new fold-up on a rim that actually fits OK first time round. Inflate, keep it inflated for a week or so so that
it get it's round form and the folding bead at least stretches a bit to it's intended form.
- try the tyre on your wanted rim by putting vegetable cooking oil on the rim and on the tyre side wall.
- inflate quick, it it doesn't pop into position, deflate and put more vegetable oil where it doesn't seat.
- keep trying and eventually it should just pop into position close to the max rated PSI; you will need a track pump!

While it's not a fast process, it is amazing that a tyre that initially wasn´t even close to fit and broke tyre levers can be
seated perfectly.

I know some people are going to get in a tizzy about vegetable oil, but it IS recommended by the likes of Michelin for seating
say tractor tyres and what not. Pure washing up liquid which I did in the past contains salts which corrodes AL rims.

 

[Ugo51]

The bead seat has a diameter of 623mm give or take, so I guess that's OK.

 

[Captain Stupido]

Re:

IME rim tape can also cause problems, especially when things are tight. Make sure it's correctly seated and not too wide...