Tubeless problems

paul.skibum
paul.skibum Posts: 4,068
edited August 2014 in MTB workshop & tech
I have my Bronson set up tubeless but it was setup by the fellas who built it and is my first foray into this realm. Been on there 2 months currently.

Got Highroller 2 tyres on WTB i23 rims - tubeless ready and 3C whatever on the tyres. As I understand it this means they are set up with only a minimal splash of sealant (if any). I am getting a continual loss of pressure in the rear. Dont have a thorn problem around Whistler, had a quick once over of the tyre and couldnt see any cuts, marks and so on but do occasionally notice that the tyre rim interface seems to be a little damp in places - not conclusive as I cant recall seeing any today but had to repressure the tyre before the ride.

So do I stick the wheel in a bucket of water and look for bubbles? Do I just whip the tyre off and have a go at reseating it? Do I need to get some sealant in there? Valve?

Suggestions?
Closet jockey wheel pimp whore.

Comments

  • supersonic
    supersonic Posts: 82,708
    Try reseating - but what pressures are you using? Low pressure and hard cornering can burp air out.
  • Try a bit more sealant.... might be worth checking where it's loosing air from in the bath etc. if its side walls, then try standing it sideways on a bucket - once over night on each side should do it if it's the tyre/rim interface, have you dinged the rim? eihter way a bit more sealant will probably sort it

    It may be that you have a residue on the inside of the tyre that is preventing the sealant from sticking... you shoul dalways scrub the inside ot tubeless tyres to remove the mould release residue - this is particularly important on continentals, but I guess most manufacturers use similar processes.
    Bikes:
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  • having ran tubless for a while and had many issues here and there i know the best method for me which i surgest you try.

    get a spray bottle the type you use for cleaning chemicles around the house £1 from the £1 shop ( obviouslly ) :)

    put some washing up liquid in there and then some warm water shake and then:

    pump tyre to 40psi

    spray tyre whilst spinning it around starting with the tread

    also spray the sidewalls ( they often leak from here especially if you did not clean the inside of the tyre first with a cleaner ( brake / carb cleaner ) as the sealent cant stick

    finally spray the valve and the surounding area ( another common place for leaks

    go mental with the spray its only water afterall and the more you add on the more you will see then wait a fewm mins

    its likley to be seaping form the sidewall or small imperfections near the tread blocks as you mention there is no obvious holes.

    if its coming from the sidewalls ( youll see fine bubbles over a few mins time) youll need to take the tyre off get some carb cleaner or brake cleaner or any other solvant and wipe the inside of the tyre out and scrub the sidewalls (inside) with this clener and a rag i always do this for all the tyres and never have issues of this nature anymore.

    if the leak is in the tread let me know what it looks like i will let you know how to deal with it .

    if it is around the bead pop the tyre off the rim soap down with your spray and re inflate. (*note i always use soapy spray to re inflate the tyre as it makes sure its seate properly.)

    if its leaking from the valve this could be one of a few issues agian if this is the case come back to me i will tell you next steps.

    good luck.
  • pilch
    pilch Posts: 1,136
    Just bosh more sealant in, it's going to make bugger all difference to the weight on that set up and at least you will have plenty slopping about to seal things.

    Pop the bead on one side, leave the tyre lever in place then just lever the bead out to make a small gap to pour sealant in, take the lever out and the bead will snap back into place, if you do it carefully you wont lose the seal & you can just pump it up to pressure again.
    A berm? were you expecting one?

    29er race

    29er bouncer
  • paul.skibum
    paul.skibum Posts: 4,068
    The fella at the shop suggested the valve might need reseating? It appears not to be burping - have upped the pressure a little on rides and its fine out and back but drops over night so its definitely a hole, seating issue or valve issue. Probably need a new tyre within a month so might get it seated by then!
    Closet jockey wheel pimp whore.
  • pilch
    pilch Posts: 1,136
    As above, washing up liquid & water on the valve will show that up, could be the sidewalls being a bit porus, add some sealant then try taking the wheel off and laying it flat (over a dustbin is good for this) overnight turn it over & do the same the follwing night. Check the bead is even both sides of the tyre.
    A berm? were you expecting one?

    29er race

    29er bouncer
  • He has said it may be the valve based on what ?

    have you done the checks with the soapy water ?

    or is that just a guess . . . .
  • paul.skibum
    paul.skibum Posts: 4,068
    I have done nothing - asked the question on here and today, whilst passing a shop I ducked in to get a fresh set of brake pads and quizzed the mechanic, who I have known for a few years, about the tyre - he said in his experience its as likely to be the valve as the bead. He gave me a little bottle of sealant and suggested I chuck a little more in to see if that sealed things up.

    I will find an appropriate spray device and have a look - living in an apartment with a shower and no bath means a trek down two flights to the car park to do this stuff - got to work up the enthusiasm when 20 seconds with the pump each ride solves the problem well enough!
    Closet jockey wheel pimp whore.
  • I have done nothing - asked the question on here and today, whilst passing a shop I ducked in to get a fresh set of brake pads and quizzed the mechanic, who I have known for a few years, about the tyre - he said in his experience its as likely to be the valve as the bead. He gave me a little bottle of sealant and suggested I chuck a little more in to see if that sealed things up.

    I will find an appropriate spray device and have a look - living in an apartment with a shower and no bath means a trek down two flights to the car park to do this stuff - got to work up the enthusiasm when 20 seconds with the pump each ride solves the problem well enough!

    save your money and time then. . . . happy pumping :)
  • felix.london
    felix.london Posts: 4,067
    its likley to be seaping form the sidewall or small imperfections near the tread blocks as you mention there is no obvious holes
    if its side walls, then try standing it sideways on a bucket

    it's a tubeless ready tyre so it wont be leaking air through the sidewalls.
    "Why have that extra tooth if you're not using it?" - Brian Lopes

    Votec V.SX Enduro 'Alpine Thug' 2012/2013 build

    Trek Session 8
  • peter413
    peter413 Posts: 4,909
    its likley to be seaping form the sidewall or small imperfections near the tread blocks as you mention there is no obvious holes
    if its side walls, then try standing it sideways on a bucket

    it's a tubeless ready tyre so it wont be leaking air through the sidewalls.

    Tubeless Ready doesn't always mean air tight, some Tubeless Ready tyres have a tubeless bead but still require sealant to be airtight.
  • its likley to be seaping form the sidewall or small imperfections near the tread blocks as you mention there is no obvious holes
    if its side walls, then try standing it sideways on a bucket

    it's a tubeless ready tyre so it wont be leaking air through the sidewalls.

    worst information ever !
  • paul.skibum
    paul.skibum Posts: 4,068
    Finally got around to doing the spray water on the tyre trick and it shows one leak point on the bead - small pin point leak.

    So do I need to pop the tyre off the rim or can I just chuck 30-40ml of sealant in through the valve and it will seal under pressure?
    Closet jockey wheel pimp whore.
  • paul.skibum
    paul.skibum Posts: 4,068
    So I chucked most of one of those little Stans sealant bottles into the tyre which seems to have solved the bead leak - but looks like I have a small hole in the sidewall too which doesnt seem to want to seal - tyre is currently supported on its side, pumped to around 40+ psi and hoping the sealant will plug the gap - its not a visible cut or hole so should seal?
    Closet jockey wheel pimp whore.
  • ride_whenever
    ride_whenever Posts: 13,279
    Sealant should do it, where do you keep the bike? Over here SC come with two bottles of Stan's, but if it's super hot you could dry that out in a couple of weeks. The little bottles will also go in. Through a Presta valve stem if you remove the core!
  • paul.skibum
    paul.skibum Posts: 4,068
    The bike was built up tubeless for me so I guess the two tubes of sealant got used in the build. I chucked the spare I bought in through the valve. I think it sealed the hole - got distracted by a leaking apartment roof this evening so did n't get round to checking post ride. Bike lives in apartment which can get hot on warm summer days.

    Going to get myself a supply of sealant although come December bike usage falls off with the arrival of the snow so probably a sealant refresh in March will be in order.
    Closet jockey wheel pimp whore.