Re Occuring Flats.

[rideabike]

(Disclamer:
Done a quick search on here and google, found some stuff, but looking for more.)


Hey all,

Fairly new to the road scence and lately Ive been having some pretty bad luck regarding flat tyres on my roadie. Seems like everytime I buy and fit a new tube, its only a few rides before it pinches or is flat again. The bike gets ridden nearly everyday, and in the last 2 weeks has now gone through 4 rear tubes. (This is only happening to the rear)

What Ive checked:

Tyres; are capable of 110psi. I weigh 65kg and am running them at 95-100. These tyres are the standard Continental 'Ultra Sport, 700x23c that came with the bike and have about 1650km on them.

Tyres; Checked them for any sort of debris, inside and outbut found nothing. (Same with the tubes).
Brakes are not rubbing.
Made sure they are not pinching the tubes when I put them on.

Wheels; Are as true as the day the bike rolled out of the bike shop.
Have not found any debris while checking them either.
Using Ritchey rim strip.

Road debris; Havent seen myself ride through anything so unless im blind(which is possible) dont think that is the issue.

Havent been smashing any gutters or irregularities in the road to my knwoledge.

I think it might be weak sidewalls in the tyres?

Any other thoughts?

(FYI Its a BMC Streetfire, small).

Thanks in advance,

Rideabike.

[Shrekmeister]

Ummm, have a feeling not enough tyre pressure...

i always run 110 to 120 on normal training rides...

not that i'm the most experienced / expert on here...

[Grover]

have you re-inflated the tube to find where the punctures are occuring? are they all in the same place? it's a good idea to always line the logo of your tyre up with the valve, then if you flat you re-inflate the punctured tube, find the whole and can then look on the tyre exactly where any debris may be stuck.

at 95-100psi you shouldn't be getting pinch flats unless you're really slamming into potholes/gutters, which you say you aren't. assuming of course your pressure gauge is accurate.

correlate any punctures in the tube with the sections on the tyre and/or rim they would have been in contact with. look for a bur on the inside of the rim, a tiny bit of glass embedded in the tyre. have you checked that the valve hole through the rim is not sharp at all and cutting the tube at the base of the valve?

[I-AM-TEH-FASTEST-11]

you can get pinch flats at any pressure

the bottom line is if you are, then change your riding style.

you may need new rim tape, rim tape can cause flats

you won't be able to see debris as you ride through it, and some disappears inside the tube after flatting.


Unfortunately, based on my experience, most of this sort of thing is generally user error. Hitting pot holes, riding through crap or bad fitting of tyres/tubes. I've seen it too often where riders claim to be smooth as silk and riding real careful, but their actions don't quite match their words. Not that they lie, it's just they generally don't notice.

Either way, if you keep getting flats on the same tyre, I would change the tyre and rim tape. Put on some Velox rim tape, it's great stuff (probably 16mm is best suited for you) and change tyres.
People claim that the Continental Gatorskin's are the best tyre for flat protection and are hugely popular as training/commute tyres. I find the 4000's are better as they seat better and rolling nicer. To even it out you could buy a 4 seasons which is basically a folding Gatorskin.
DON'T use tyre liners or slime. It's useless and crap. Seriously.

So up your pressure, always 110 minimum unless it's really wet and slippery (even then I wouldn't really bother dropping) and consider changing tyres to something better and some nice new rim tape.

As an after thought, I remember a customer swearing he had never ridden through glass (he had a similar problem and wanted warranty on his tyre and tubes). He had searched his tyre multiple times (apparantly). I looked and found 15 pieces of glass in about 5 minutes. They are hard to see if you don't know what to look for, but any half decent mechanic can usually find more than your average rider.


OK there it is, sorry if it's a little vauge, cause I'm tired. I tried to address every point.

it's a lot easier to sort this stuff out by looking (as a mechanic) than just by talking to you, there's tonnes of causes, but hopefully one of the options above or within will help you.

Cheers

[ScottD]

If your tyres are only rated up to 110psi I'de say there not the best quality tyres. Grab yourself some vittoria Rubino Pro Tech's. Same ting as the Gatorskins (they have a kevlar sidewall) but ride a whole lot nicer and are easier to remove.

Replace your tyres, tubes and rim tape and that should eliminate your problems.
I pump my tyres up to 120psi before every ride and 135psi for racing.

[Christo]

Got to be tyre pressure - 90-100 won't handle a 80kg+ rider (I"m right aren't I? It's alright - it happens to the best of us - I just figure it's more to love)

Go to 120 psi and see how you travel - grover's advice is really good - listen to him if higher pressure fails but I doubt it will.

[tofer]

It could be anything. Depends on how old the tyre is. I would just replace the tyre. I mean i've had 3 punctures in the past 2 weeks because my tyre is dead. I just don't have my tyres i ordered online yet, so i keep on replacing them with new tubes, or repairing the old ones.

Check you're tyre for tiny specks of glass/rocks, anything could cause the flat. Also try inflating you're tyre up a little more. maybe to 110psi/120psi. I'm riding Continental gp4000 (never had a problem with them) at 120psi. I'm only 65-70kg. I also try to check my tyres once a month, and pull out all glass/rocks/crap. it's best to pull it all out with the tyre deflated.

[alchemist]

I weigh 65kg and am running them at 95-100. These tires are the standard Continental 'Ultra Sport, 700x23c that came with the bike and have about 1650km on them.


Got to be tyre pressure - 90-100 won't handle a 80kg+ rider (I"m right aren't I? It's alright - it happens to the best of us - I just figure it's more to love)

Nope. :p
........

[DarrenHunt]

higher pressure... 120psi is ultimate for no flats and comfort
new tyres... something decent, i run GP4000s atm, had normal 4000's and never had a flat, gatorskins are also good, but they're heavier and dont roll as well.
i used to get heaps of flats, almost every ride until i put on the 4000's and put more pressure in my tyres.

[rideabike]

Cheers everyone for all the advice, some excellent stuff in there I'd never even thought about.

Just got back from the LBS with a set of gatorskins, new tubes and some new rim tape.

Upon triple checking the existing tyres still no signs of glass. Rim tape was a little rough though in one section so was a bit suss about that.

New tape, tyres and tubes are on and good to go, checked everything and now are running 120psi.

Lined the Tyre logo up with the valve too.

Could feel the difference in the sidewalls between the new and existing tyres straight away and am somewhat confident that this will make a difference in reducing the risk of flats.

Thanks again everyone who replied, lots of great stuff in there.

Cheers,

Rideabike.

[Onegear]

The gatorskins should help I got nine months of riding nearly every day without a single flat on the last set.

[giraffe boy]

If you're commuting along the side of a freeway, like the M4, you may have a sliver of wire on the tyre. It will prick a small hole in the tube every time you put a tube in.

It's form the truck retreads that are all over the place. They can wriggle sideways through the tyre - don't ask me how, it's just what's happened to me.

Only way I found to reliably find them was to run my unprotected finger inside the tyre until I felt it - do it slowly so you don't snap yourself with it.

I now carry a very small pair of pliers for pulling little bits of wire like this out.

gb