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Calling Techy experts
OK here is the challenge to all the folks who are at one with their cycles....
I have been having a terrible run of flat tyres after many years of barely any. Virtually every ride. To the point where I am thinking the Gods are telling me its time to covert to tubeless (which I am).
So it goes like this. Go for the usual rides, a couple of days later I look at the bike and have a flat. On occaision it has been a slow leak on the ride but the last two have been after a successful weekend of riding with no incling of trouble. The rides have not been particularly rocky or anything else to detrimental.
Have checked the rims and tyre casings and nothing to pinpoint a cause. The valves are ok.
Just to make it interesting..... and this is where it gets really interesting....different set of rims and different set tyres both brand new but its been the front rim of both sets so far.
Anyone have any clues what might be causing this run of slow leaks?
Interested in your theories.
Thanks
Craig
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Are you using Stans? Worth a go, I've not had a flat since using it.
Interesting timing! This weekend I just converted mine to tubeless! Haven't ridden on them yet (too much rain
) but they look ok.
I didn't use the Stans or equivalent kits as I thought they were way over-priced. Instead I opted for the "Ghetto tubeless" method (search Youtube). There's a great description and discussion on how to do it here: http://www.rotorburn.com/forums/showthread.php?t...
Cost: $10 for rim tape (one roll will do about 20 rims) and $34 for the latex (enough for 30 or more tyres.) Plus two old tubes laying around I butchered for the valves.
Could be worth you giving it a try!
I know that I could convert to tubeless, thats the easy part ....
But I want to know whats going on, my mind wont rest till I find the answer.
I am hoping those with an intiamate knowledge of all things bike could shed some possible reasons for this phenomenon.
Hi Craigster
I've watched you. You are just going too hard. Suggest you convert to better than tubeless: sole-less....
That's my next upgrade.
Rgds, Hans
____________________________________________
"I thought of that while riding my bike."
Albert Einstein, on discovering the theory of relativity.
soulfull than soul-less.
Craig, on a serious note, I don't have a lot of experience with leaks, particularly slow ones like you describe but can I suggest you remove your wheels from your bike, make sure they are over inflated and then sink them in a bath with water in it. wipe them over whilst still under water to remove all the air bubbles that will be "carrried" in. Leave them there for a while and then come back and look for the bubble stream that will show where the leak is coming from. Mark this with some chalk.
Remove your tubes and make sure you mark them as well so you know what part of the tube aligns with what part of the wheel they were removed from. Inflate the tubes and then sit them in the bath for a while as well.
This may not initially explain what is happening but it will show you where the air is leaking from. Once you know that, it then makes it much easier to work out what is causing it. As long as you know which way the tube sat in the wheel then you can look in that area for what is causing the slow leak.
Good luck.
Look for things like slight dings in your rim, spokes slightly too long that are now rubbing on the tubes, grit or other crap in your valves.
Can't no one keep you off da walkin trails with that set up.
.....that a anti bike riding partner would stick a needle in his bike tyres just to prove her love
Only a thought
Greg
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The Liver is Evil and must be punished
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Couple of questions
What brand of tubes are you buying
What kind of tyres do you have
How old are your tubes and tyres
How do you put your tubes in i.e bit of talc a rim strip etc
i know how you feel, i will have really bad runs as well where i flat every ride where as i havent had a flat in three months. In the end i came to the conclusion that it was the puncture strip causing the punctures {definition of irony} and i hadn't put any talc in
Tubes: Specialized
Tyres: Intense and Kenda Small Block 8. Both sets brand new.
Talc: Yes but only recently since Harry converted me.
Rim strip: Standard rim tape is installed.
I am not sure what you will deduce from this but the only thing different is the Talc.
Damn it, I think we are on to something. The Talc is too coarse and/or the friction at pressure points is wearing the small holes.
Time to change Talc or leave it out all together me thinks (didnt smell any good anyway, it was some cheap arse stuff I found lying about)
Anyone want to support or debunc this theory?
What pressures are you running? Riding on the road?
Pressures are 32-34 PSI
Rarely ride on the road.
One flat was after The Mont and the other after the Mountains ride last week.. and as per the topic, they both went down days later.
Brand new tubes too.
I am going to stick with the Talc theory and the small particles rubbing holes in the tubes. It's the only thing that I have changed.
You should have been using that since day 1.
Report back after your bath tonight please
Was very careful to maintain orientation of the tube and rim then checked the tubes and rims where the very tiny hole was found to be. Nothing.
Now please note that this has happened on two different sets of rims/tyres recently and the only difference is TALC. (Tubes come pre talc'ed but this cheap stuff I added on recommendation is in addition).
If I install new tubes, inflate and submerse, what should I see? It wont be leaking truck loads of air (if any at this point), and if there is a repeat of this miniscule hole it may only leak a small amount of air into the tyre casing which would then leak out at any spoke hole or other leaky bit. I'm unconvinced with your wisdom ye MODold fart.
Please tell me more.
Craig
I just wanted to have a laugh when you reported back
You didn't mention in your original post that you had located very tiny holes so I had presumed, incorrectly of course, that you couldn't find any hole at all in the tubes.
A couple of thoughts, and listen because this is going to drain me, I'm normally only allowed one a day.
Many many years ago i had a similar thing happen on my roadie. Front wheel, no obvious debri, no punctures or pinch flats. It turned out that the "Tuff Stuff" tape I was using wore a very small hole in the tube where it overlaped. The edge created at this point was the culprit. This obviously isn't the cause with you, so a couple more questions
do you semi inflate the tubes before you instal them?
are the tubes you have used been carried in your backpack for any length of time?
If no to the semi inflate then it is possible that you might be creating a very small "crease" in the tube or a wear point as you inflate them in the tyre. If yes to the semi inflate then it is also possible that you are putting a very small pinch in them as you instal the tyre. It is possible that this won't be evident until you have then ridden on them for a while
If yes to the backpack bit then I remember someone else hear comment that the valves had been rubbing very small holes in the tubes. This wasn't visible when installing unless you went looking for it and depending on how the tube is folded in packaging it won't necessarily correspond with anything or even be near the valve once the tube has been installed and then removed.
Unless the talc is very very coarse I can't see it being the problem. It will make the tube "slide" a little with in the tyre but there has to be something there for it to rub a hole on, and this would take time I think.
Of course the other thing is that this has happened on two seperate wheels, only once each if i am reading correctly, which might just be coincidence. Let it happen a third time then you should be good for another couple of years, bad luck in threes and all that.
If you're tubes are latex (generally green or blue in colour) this is quite common as
latex tubes are slightly porous and will need to be pumped up about once a week, it's a good excuse to buy a track pump
A small price to pay
I've never used talc, not heard about it. But I don't think it could be abrasive. What it could do though is allow the inner tune to move against the inside of the tyre and rim. That movement would be bad. I bit of talc over a puncture repair is fine, but the whole inside, what's that all about???
What do the holes look like? Abrasions?
Hey Craig you said you were using specialized tubes, I have used them in the past and only got a few rides on them before they punctured, I found them way to thin.
Well I can explain the theory behind talc.
It has a two fold reason. First is to remove the friction between tyre and tube thus reducing rolling resistance of tyres. Eg cause they more free mold to the shape of the ground and thus energy not lost in a tyre bouncing off stuff. (a very roadie reason)
The second reason is that it could help with reducing the risk of pinch flats. the tube moves out of way when you hit a big rock etc and prevents the dreaded snake bit action.
I have used talc in the past for both reasons. To me IT WORKED. I think most of it is in tjhe head but I felt faster and I didnt get pinch flats.
Back on topic.... I would put some new rim tape on those rims to start. I would be thinking that there is something small like sand? or you have a leaking valve or two? If it takes a couple of days to go down i wouldnt worry about it just pump them when you want to ride.....
FYI. I need to pump up my roadie tyres at least once a week
I have to pump up my roadie tyres every 100k
One thing that i found {and it may be coincidental} but i was having a lot of trouble with flats. To the point where I bought everything for the ghetto tubeless set up and even package taped the rim. I then had second thoughts as I like to swap my tyres around a fair bit so didn't get any further than that and i put the rimstrips back on over the tape. i haven't had a flat since. again could be coincidental
Talc'ing the tube stops the tube sticking to the inside of the tyre. Under heavy braking especially when running high pressures the tyre can Rotate on the rim, if the tube is stuck to the tyre it will tear at the valve where it is connected to the rim, something has to give.
Talc will never wear a hole in your tubes, however sand & dirt over time will.
Take out the valve core from your tube, whack in some white latex liquid (Stan's etc)and have a look at the tube again after a few rides. I know you won't see your tube is flat because of the liquid, but the liquid will solidify at the spot any air is leaking from. Hey presto! Now all you have to do is work out why; again wise to work the tube so everything's in the same posi it was on the bike.
I would be trying a different brand of tube. See if that makes a difference. Then if you don't get a flat, you'll know (as said above) the tube walls were too thin on the Spesh ones and that was the culpret.
Good luck with it!
... tubeless.
It's so easy - weighs less and I've not had one puncture running tubeless in two years... (touch wood).
Why would you not?
Now running 30psi in the rear, 26psi in the front (have been gradually reducing the pressure).
Cheers
Nic
Cheap chubes leak.
I have different tyres for different conditions. For normal trail riding I have Larsen 2.35. For racing I have High roller and crossmark and for wet i have a set of IRC somethings . Swapping them around with tubeless is messy and time consuming. I will convert eventually but probably when i get tubeless rims