Lumpy Tyres on Carbon Clincher

gdiddy
gdiddy Posts: 24
edited September 2018 in Workshop
Hi all. Thanks in advance for any help.

So I'm in France for the week and summited Ventoux yesterday- it was so hard but something off the bucket list ticked off!

A minor problem was my front tyre exploded at the summit, so I missed the fun descent.

I bought a brand new Vittoria Corsa G+ today and it's an extremely tight fit onto the Reynolds Strike SLG 62mm wheels I have. So tight that however much I try, parts of the beading keep getting caught inside the inner rim/lip ( see image).

http://i1376.photobucket.com/albums/ah5 ... ncmqiw.jpg

<a href="http://s1376.photobucket.com/user/garymotion/media/IMG_20180920_195930_resized_20180920_080256994_zpsx2ncmqiw.jpg.html&quot; target="_blank"><img src="http://i1376.photobucket.com/albums/ah5/garymotion/IMG_20180920_195930_resized_20180920_080256994_zpsx2ncmqiw.jpg&quot; border="0" alt=" photo IMG_20180920_195930_resized_20180920_080256994_zpsx2ncmqiw.jpg"/></a>

So once I pump them up, they're really lump and uneven...which I think may have be the reason the first tyre exploded.

I've tried pushing one side of the tyre onto the lip, then thumbing the other side onto the clincher. But as they're so tight, I have to get levers and as soon I force the other side onto the main rim, the other slips into the inner lip/rim.

Any help would be great. I'd say I'm pretty new to cycling so don't have all the technical skills, but I've got a couple of big rides planned over the next few days!

Thank you

Comments

  • trailflow
    trailflow Posts: 1,311
    What previous tyre did you use ? if it's a cotton cased tyre like a veloflex/corsa, and your carbon rim has a sharp edge on the bead hook, it could have cut the sidewall of the cotton tyre. Causing the tube to be exposed and subsequently punctured. Veloflex tyres come with a warning about carbon rims that have sharp edges. So that's one possibilty.

    If possible, can you post a picture of the lumpyness of the installed tyre ?

    Are your inner tubes normal ? and not thick heavy slime tubes ?

    i cannot see how the tyres would be that lumpy unless your inner tube was too big, or your carbon rim has in fact delaminated in places and buldged out.

    Probably, your inner tube got caught between the rim and tyre from a poor installation. To check they are seated correctly, when the inner tube and tyre is installed (without air), you can rotate the tyre and pinch and pull the tyre all the way around the wheel.

    Then put a small amount of air in the tyre. Then do the same again.

    Lots of tyres are difficult to get on especially when brand new. Try this technique in this video
    https://www.youtube.com/watch?v=jvvXrlAUUfU

    If your still having difficulty. Some rim tapes can be thicker than others and can make the tyre harder to seat correctly. You could try a different brand of rim tape, or a thinner alternative to rim tape is a couple of layers of tubeless 21mm tape (like Tesa 4289).
  • gdiddy
    gdiddy Posts: 24
    trailflow wrote:
    What previous tyre did you use ? if it's a cotton cased tyre like a veloflex/corsa, and your arbon rim has a sharp edge on the bead hook, it could have cut the sidewall of the the cotton tyre. Causing the tube to be exposed and subsequently puntured. Veloflex tyres come with a warning about carbon rims that have sharp edges. So that's one possibilty.

    If possible, can you post a picture of the lumpyness of the installed tyre ?

    Are your inner tubes normal ? and not thick heavy slime tubes ?

    i cannot see how the tyres would be that lumpy unless your inner tube was too big, or your carbon rim has in fact delaminated in places and buldged out.

    Your inner tube probably got caught between the rim and tyre from a poor installation. To check they are seated correctly, when the inner tube and tyre is installed (without air), you can rotate the tyre and pinch and pull the tyre all the way around the wheel.

    Then put a small amount of air in the tyre. Then do the same again.

    Lots of tyres are difficult to get on especially when brand new. Try this technique in this video
    https://www.youtube.com/watch?v=jvvXrlAUUfU

    If your still having difficulty. Some rim tapes can be thicker than others and can make the tyre harder to seat correctly. You could try a different brand of rim tape, or a thinner alternative to rim tape is a couple of layers of tubeless 21mm tape (like Tesa 4289).

    Hi mate, thanks for getting back to me.

    The previous tyre was a Vittoria Corsa G+ also. I think the psi was maybe too high, which caused the blow out.

    I've put a tiny bit of air into the inner, pushed it back and forth around the whole rim to make sure it's there is no inner caught, and got a consitent (if tight) fit around the whole wheel. But I think I've pinpointed the problem now, but can't seem to fix it;

    What's happening, is when I start to inflate the inner, the tyre beading is expanding out to hit the rim wall, except for the part directly opposite the valve- where it's still stuck in the central rim groove. So I think 'lumpy' was probably not the correct description, think more of a few mm difference in depth at that part of the wheel, which when ridden feels like a bit of a 'bump' each time you hit it?

    Wheels are 700c 23-28mm. Tyres are 25mm. and Inners are 700c 18-25mm...so that all seems to amke sense. The Rims and Tyres are tubeless ready, which I think may be creating the tightness?

    Hope that makes sense?
  • trailflow
    trailflow Posts: 1,311
    Have you tried re-inflating, and/or re-positioning the tyre ? does the problem re-occur in the same spot ?

    Your description now makes more sense. Try adding some talc powder to the tube,tyre case and bead. It sound like the inner tube is getting caught or something maybe from high friction. I never experienced a tyre bead that gets stuck in the inner groove. so thats the only idea i've got.
  • crankycrank
    crankycrank Posts: 1,830
    Did you push the tube's valve stem into the tyre partially before inflating? Not doing this can keep the tyre from seating on the rim and could possibly be the reason the tyre can't quite crawl onto the rim bead 180deg. away from the valve stem.
  • gdiddy
    gdiddy Posts: 24
    trailflow wrote:
    Have you tried re-inflating, and/or re-positioning the tyre ? does the problem re-occur in the same spot ?

    Your description now makes more sense. Try adding some talc powder to the tube,tyre case and bead. It sound like the inner tube is getting caught or something maybe from high friction. I never experienced a tyre bead that gets stuck in the inner groove. so thats the only idea i've got.

    Different spots around the tyre.

    The solution I've found was washing up liquid. If I rub a layer of washing up liquid around the inner rim lip, fit the tyre, then inflate slowly/deflate/inflate- then you can hear the tyre beading snapping to the rim wall once the psi increases.

    Should I worry about washing up liquid and re-do this method with talc do you think?

    Thanks again for your advice
  • gdiddy
    gdiddy Posts: 24
    crankycrank wrote:
    Did you push the tube's valve stem into the tyre partially before inflating? Not doing this can keep the tyre from seating on the rim and could possibly be the reason the tyre can't quite crawl onto the rim bead 180deg. away from the valve stem.

    Hi mate, yep tried that. The area around the valve was fine, but it tends to be other random spots around the wheel.

    The solution I found was washing up liquid rubbed on inner lip, and a lot of inflating/deflating until the you can hear the beading snap to the outer rim.
  • rafletcher
    rafletcher Posts: 1,235
    I was going to suggest dilute detergent - I use it regularly to get tubeless tyres to seat properly and easily. Washing up liquid does contain salt (as a water softener and to promote bubbles - looks good on the ads) but not so much that I's wory about using a small amount. If you do it again dilute it a bit to reduce the amount used is all I'd say.
  • cougie
    cougie Posts: 22,512
    What PSI are you running the tyres at ?
  • gdiddy
    gdiddy Posts: 24
    cougie wrote:
    What PSI are you running the tyres at ?

    100
  • imposter2.0
    imposter2.0 Posts: 12,028
    The beads will usually pop into place with enough inflation pressure - depending on the rim/tyre combo that might mean going some way over 100psi. Which may or may not be a good idea on a carbon clincher, depending on if there is a pressure limit on the rim. Either way, that method works for me, but the only clincher rims I have here are alu, not carbon...
  • sungod
    sungod Posts: 16,521
    you say the tyre 'exploded'

    in what way? did the casing fail? exactly where? was it cut along the line of the bead?

    looking at your picture of the rim, that edge looks nasty, as mentioned above the rim can cut the sidewall, the corsa g+ sidewalls are certainly thin enough to be damaged this way
    my bike - faster than god's and twice as shiny
  • CRAIGO5000
    CRAIGO5000 Posts: 697
    The Strike's are notoriously hard to puncture fix IF you don't use the channel in the centre of the rim to your advantage.

    I did mine by hand without levers but it takes time to embed the tyre beads inside the rim centre.

    The bead will "pop" and "clang" to the rim wall upon inflating. Mine fully seat at the 90psi mark. If not, you've likely pinched the tube and that is stopping the process - hence why you also punctured.
    Ribble Stealth/SRAM Force
    2007 Specialized Allez (Double) FCN - 3
  • zefs
    zefs Posts: 484
    I would agree with placing the beads in the center well of the rim, sometimes depending on the combo you need to do it a few times throughout the wheel circumference. It makes the last "hard" part mounting easier.

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