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How the hell do you break the bead on UST tyres?
My trust Aredents have let me down. Some how i managed to stake a decent size hole in the centre of the rear tyre. Now these tyres have copped some abuse around, LCNP, Terrey Hills, Appin and Blue Mountains, over the last 2 years, never a problem. Hit singleton on the weekend, one of the smoothest tracks around. 5km in, there was a hiss and then a ferris wheel of stans fluid. Had a tube no problem, quick fix. NO. Do you think I could break the love a fair my Ardents and UST Fulcrum rims were having. No chance. Obviously this is why they are called Maxxis LUST. So I McGulviered the hole with some electrical tape I always carry and walk/rode back to the car.
So what is the catch to getting these tyres off?
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On good quality rims the centre of the rim is recessed. You need to squeeze the tyre in so that the bead lines up with the recessed part of the rim. Keeping one side of the tyre in the recessed part allows you to pull the tyre at the opposite side of the wheel over the rim. I can put my Maxxis LUST tyres on and off without using any tools at all.
Do a Google image search on "bike rim cross section" and you'll see what I mean.
As shown above push the tyre into the centre of the rim with your thumbs. Its not that hard
The title of the OPs post suggests this is about breaking the bead rather than getting the tyre off the rim.
I'm not sure if there's a better method for mountain bike wheels, but I've done a fair few tubeless motorbike tyres which often have the same issue. I tend to use two or three tyre levers spaced a couple of inches apart to try and 'ease' the tyre away from the rim. Once the bead's broken in one area the rest should follow pretty easily. Then just repeat on the other side, as even though there's no pressure, the tyre can stick pretty well.
Difficulty of breaking the tyre bead on UST tyres seems to be highly dependent on hand/thumb strength and type/age of sealant. I often find it hard to break the bead, especially if the tyres have been on for a long time.
When thumb strength fails I find that this works - lay the wheel horizontally on the ground, stand on the deflated tyre (one foot on each side of the wheel) then pull rim away from tyre bead.
Thank you for pointing that out Mike_H but I can read.
Its actually the same procdure except you dont take the tyre off!
If you read Zooms post, he seems to be describing how to remove the tyre from the rim - not how to break the bead between the tyre and the rim.
I didn't see anything in either his or your post which actually helps with the OPs problem of breaking the bead.
I have to apologise somewhat. I've never had a problem breaking the bead from the rim so I answered what I thought he must have meant.
I will say it slowly for you guys, use your thumbs (both of them) to push the bead/tyre into the centre of the rim.
FFS its a very basic thing to do.
and I'll say this grimacing - not if you got arthritic hands it isn't
- or fused finger joints. If I need to break bead in the bush I stand on the tyre bead opposite the valve, sometimes need to push the rim down at valve while standing on tyre, once got it started its fairly easy after that.
Oldernslower, when you stand on the tyre to break the bead, do it at 90 degrees to the valve.
My Bad explanation - I do it 180 degree from the valve - but anywhere from 90 to 270 seems to work ok
It's just that if you're trying to pull a tyre off, the bead can't slip into the centre of the rim because the valve is in the way. If you pull the tyre off with the valve not at 180 degrees its easier.
Another thing to point out is that if the Stans fluid has been sitting in there for ~2 years, it is probably no longer functional.
I got a significant punture recently - I think a stud almost tore off - and has the same ferriswheel of Stan's as you. When I eventually got around to reverting the wheel to tubeless, it needed a good clean out with soapy water, and a significant quantity of Stan's to fill the hole. I actually had to go through the process of setting it up, let the wheel sit for a day or so at a lowish pressure of 40psi (I say lowish as I take it up to 80psi to seat the bead properly and make sure any small air gaps get filled with goo), let it plug the leak and dry, and then top it up again with more Stan's, re-seat the bead, etc.
If it were a freshly prepared tubeless setup, it may well have plugged your leak.
cheers,
Grant.
At 80 PSI I wouldn't be surprised if your rims split in the middle.
Had that happen more than once. When it hits your fingers it stings more than getting the cane off Mr Wheeler, my old deputy principal.
Wear your protective glasses, boys and girls.
are your rims made of cheese?
Fine, 80psi may be overkill, but it wont damage a decent rim/tyre.
No, the bead stretched over the lip, hit me in the fingers and spraypainted the garage interior with sealant.
Normally the rim splits down the middle where the spoke holes are. The bigger the tyre the greater the force. Do the maths!
"No, the bead stretched over the lip, hit me in the fingers and spraypainted the garage interior with sealant. "
mmm, thats how I discovered that tight fitting schwalbes have an advanatge over easy to fit tyres - one you dont get a cold day smash across the hands, and 2, the tyres dont burp air.