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Tubeless tyre issue

Lach's picture

By Lach - Posted on 26 January 2015

Have recently put a pair of Conti Race Kings (protection model) on the Niner, on 3 year old set of Stans rims. Beaded up OK, but they struggle to hold air for varying periods. Can be fine for a couple of days and then go down overnight. Rear went from 28 psi to 20 psi on a 2 hr ride last outing. Had no problems previously with a mix of CrossMaxs (LUST) and a tubeless ready Kratos. Sealant was the end of a 18 month old bottle. Rims cleaned prior to fitting and tape seemed in OK nick.

Any suggestions?

hawkeye's picture

I've used the Rubena sealant and don't rate it - dries up very fast and leaves a real thick coating inside the tyre. Stans is much better from a service life perspective.

Some sidewalls are more porous than others. I found the same issue as you with the OEM TLR Racing Ralphs that came with my Scalpel, it took a few weeks for the sealant to plug the porous sidewalls. The snakeskin replacements were much better, albeit heavier.

hawkeye's picture

Double post

Lach's picture

... but as I said, it was getting on a bit. I bought some Spex from the LBS to replace it, so I might have another go with that.

fairy1's picture

They seem to have a pretty bad reputation for porous sidewalls and if it's not made in Germany don't waste perfectly good sealant on a bad tyre. The German ones are good the others are pretty rubbish, I haven't tried non German Pure Grip compound so they may be okay....?

Tom M's picture

Just mounted a conti xking race sport front and had the same problem.

I put the wheel/tire in a bath and it's very slow leaks all over the side wall. I even cleaned the inside with brake clean like suggested prior to mounting to remove the mould release.

Any way I ended up usings 5 ounces(normaly use 2oz) of stans (2.4 wide 29er), pump up to 45psi and lay horizontal for a few hours then re pump and flip over. After 2 days of this I rode it and it held up. Now have 3 rides on it and seems its on the way to sealing up.

Very happy with the black chilli compound, rolls very fast. After the first ride I was thinking of ordering a race king for the rear I was so impressed.

fairy1's picture

Not sure if it was on here but I read someone cleaned the inside of the tyre and threw on a couple of coats of Plasti Dip. Sounded pretty odd but supposedly worked, you could possibly add a bit more Latex to your goo.

Lach's picture

Have tried re-sealing with some new sealant in greater quantity. There was already a reasonable sized booger in there which had formed in just a couple of weeks with the old sealant. Beaded up OK again again and after a little bit of ooze at one spot on the rim, seems to have settled down. Tomorrow will tell I suppose. BTW they were zee German manufactured Conti's.

fairy1's picture

Yeah if the sidewalls keep leaking you get boogers in very little time as the goo will go off with the air rushing out. With my Butcher the more the casing deformed when riding the more air and goo I'd lose through the sidewall, it was good new but went to poop pretty quickly, works well with a tube though.

MrMez's picture

I love UST (real tubeless), but this sealant business just seems like such a fn pia.

Won't you be better off using a proper UST (not TR) tire with some good rim tape like Orange Seal and avoiding sealant.
Or even just use a tube?

Lach's picture

.. I'm enjoying being able to run <30 psi without worrying about pinch flats. Up until these Conti tyres, I'd had no problems other than a slightly greater rate of deflation. Just meant a bit more diligence in checking tyre pressure before heading out.

radar36's picture

Lots of pages have home made recipes for sealant. Latex isn't always compatible with your tyre compound and sealants like Stans will form boogers very quickly. Take a look on the interweb for homemade brews. Guys are chucking sparkles and other things in there to seal up holes. At least you won't get lost!!

fairy1's picture

Yup, I regretted using fluro yellow glitter pretty quickly.

Once I find a decent ~1kg AM tyre I'll go back to tubeless, it's horrible with normal AM tyres. Burps, rim slices through the top of the tyre, tyres leaking air etc etc, so much more trouble than tubes.

hawkeye's picture

(well, maybe a little bit lol) but if you're having so many issues maybe you're doing it wrong? Tubeless has been pretty much trouble free for me.

Mind you I'm under 80kg and don't push the envelope that hard.

Are you using proper tubeless rims or a conversion? UST tyres?

fairy1's picture

It's pretty much all me, I'm running Flow EX rims but I weigh near 110 in gear and like my tyres at 25Psi. I'm thinking of moving to WTB Frequency Team rims as the hook should reduce the chance of the rim slicing the tyre and they should burp less often(I think).

Have never had proper UST tyres but have run some tubeless compatible ones or whatever they are called. I just need a tyre with a proper sidewall, so if you know of any ~2.3" AM tyres that are up round a kilo I'd like to know what's out there.

A Speshi butcher with an SX casing or a Conti Baron would be perfect but neither seem to come to Oz.

hawkeye's picture

UST tyres have a lot more rubber in the sidewalls, so they should meet your requirements for both weight and sidewall strength.

TLR are much lighter, to the point where the sidewalls wont hold air by themselves and sealant is necessary.

I guess the view was taken that most customers use sealant anyway, so let's cut back on the rubber and save on some materials cost (better margin) and we can then crow about their marvellous light weight - a win all round. Except for folks like yourself in the Clydesdale category. Sad

I'm not sure how that works long term for non-Clydesdale folks anyhoo - you're still having to add back the rubber in the form of extra sealant, so the weight saving is probably illusory.

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