Getting Flats!

[bisearoet]

I hope some of you experienced riders can help me with this one:

I recently purchased a Giant Defy 2 (and love it), but I am experiencing a frustrating problem. I have had 5 flats in the 130 miles I have ridden so far. All flats have been on the rear tire, and the last one was a blowout.

I am hoping this is not relevant, but I tip the scales at 265.

A tech at the lbs suggested a couple of things: 1) go from 700x25 to 700x28 and 2) under inflate (he suggested 110#). I have yet to try these, since I used my last tubes this morning.

With the bike, I bought ultralight tubes, and when I needed more tubes, the salesperson at the lbs suggested the regular tubes, which he claimed would be more durable. I was fine with that since they were about 1/2 the price. I have flattened both types.

I have limited my riding to the Cardinal Greenway, which is a paved, former rail-bed here in Indiana. In other words, I would think it is about the best roadway I could be riding.

If anyone has any suggestions, I would sure appreciate hearing them.

 

[TheRo0sTer]

Tire liners
Gator Skins
Armadillos

What kind of flats are you getting? I weigh 240 and I run standard tires and standard tubes. 700cx25 Front: 45 psi and Rear: 60 more than enough TP to support me. 110psi is crazy high for a 25. I think if you don't want to buy new tires... get liners. Spend some more and get one of the kevlar tires.

 

[thepieeatingjay]

You bought the bike new? And just to clarify, you're blowing tubes, not tires off the rims?

Last bike i bought new had cheapest tubes known to man. Since tubes are relatively cheap, I'd start there. Next thing would be to get a stronger rear tire, like one of the Kevlar ones. Big bike companies sometimes skimp on tires too.

 

[blastguardgear]

You really need to spend a bit of time figuring out what caused the flats. Some things to look out for are:
- wire or glass shards in the tire casing (get them out)
- exposed spoke heads/holes in the wheel bed (check the rim tape)
- improperly mounted tire, tube caught between the rim and the bead

The only blowouts I have had were caused by that last one.

 

[tarverten]

Perhaps your flat repairing technique is not the best. You may be pinching the tubes when you install them or making some other mistake. You don't say which wheel, front, rear, both. You have to examine the tire after each flat to find the cause and make sure it has been removed. You have to find out whether the latest hole in the tube is in the same place as a previous one. It could be so many things like spoke holes that are not taped over, pinch flats due to insufficient inflation for your weight, pinch flats due to improper tube installation, glass or a sharp stone that is stuck in the tire and you haven't gotten out...

 

[Totalarmordestine]

Exposed spoke ends are a very unlikely cause of flats these days, because the V-shaped rims keep the spoke ends very far from the tubes. But uncovered spoke holes in the rim bed could be the problem. The tube expands into the hole and cuts itself on the edge of the hole.

 

[namestakensuck]

Orange seal. Get orange seal. It makes the thorns weep. Weep thorns weep.

 

[shadowsupernature]

Multiple flats mean that you either have really bad luck or, as others have said, the repair process wasn't the best.

When you get a flat, always figure out what caused it. Find the shard of glass, thorn, nail, whatever, that caused it. Before removing the tire, see if there is anything on the outside of the tire that could have punctured the tire. Next remove the tube and carefully keep it aligned with the wheel. Pump up the tube a little and see where it leaks. Put the tube up against the tire with the presta valve near the hole in the rim. You can now see where the problem is in the tire (or maybe wheel). Remove what is sticking through the tire that cause the flat. Folding up a dollar bill and putting it inside the tire over where the puncture happened is an excellent way to 'boot' the tire and keep something else from coming through the hole again.

If using patches with the little tube of glue, the biggest mistake is now waiting about 5 minutes for the glue to dry before applying the patch. Technically the glue isn't drying as much as melting the rubber tube so the patch will stick better. This takes time.

I'm guess that the blowout was due to not installing the tube correctly. After putting the tube and tire back onto the rim, make sure to check between the tire and rim to make sure that the tube isn't stuck there. Make sure to check all the way around the tire and on both sides of the rim.

I'm 215 lbs and use Continental Grand Prix 4000s 700x25 tires inflated to around 100 psi. Bigger tires at lower pressures could help prevent punctures. So could a more puncture resistant tire. Just don't go too low or snakebite pinch flats could happen. A larger tire at 110 psi seems reasonable to me.

 

[Froze]

I agree with your LBS on going with the larger tires, but not sure by what he meant by underinflate. Take the guess work and opinions out of the equation and use this calculator instead: http://www.dorkypantsr.us/bike-tire-pressure-calculator.html Use the second calculator and enter your fully dressed ready to ride body weight plus your fully equipped ready to ride bicycle weight, enter your tire size front and rear and read your recommended PSI. The only exclusion to this is if the tire package has their own recommended weight/psi scale then use that scale instead.

As far as tires go, if the inflation is correct you shouldn't get any snake bike flats regardless of the tire. If you're getting flats from road debris then you need a better tire at warding off flats. There are kinds of good highly flat resistant tires on the market today, Vittoria Rubino Pro Slick, Hutchinson Intensive Longwearing (not the tubeless version), Specialized Roubaix Pro, Specialized All Condition Armadillo, Michelin Pro 4 Endurance, Maxxis Re-Fuseor the Continental Gator Hardshell (their other tires suck, they use ultra thin sidewalls that are very susceptible to damage). Some of these tires are very expensive but if wait for sales and end of season closeouts you can get really good deals from Performance Bike and Nashbar, and on Amazon. Maxxis Re Fuse is the best buy tire when no tires are on sale. I never pay more than $32 for a tire and I end up with $60 and more retail tires.

Most tire liners suck. The plastic strip kind like the Mr Tuffy and Slime don't work that great plus there is quite a hassle to make sure the liner stays in place after the tube is installed and you start to air up the tire. I found one liner that works superbly, and that's the Panaracer FlatAway, however it's a one time use liner and it cost about $15 each, but their a lot tougher than a Mr Tuffy, how tough you ask? This tough. I took this tack: http://www.lowes.com/pd_58218-37672-532362___?productId=3036042&pl=1&Ntt=tacks And tried to push it through the FlatAway liner, when that failed I put my thumb (like the idiot that I am) over the tack to exert more pressure and still failed to penetrate the liner, but the tack went right through a piece of Mr Tuffy I had with little difficulty. Next I discovered while sizing the liner for the tire I was have a horrible time trying to cut the liner with my scissors and my hand was even hurting, but those same scissors cut the Mr Tuffy like butter. The Panaracer FlatAway liner has a sticky backing, you peel off the paper as you lay the liner inside the tire, the sticky side will stick to the tire and will not come out of place as you put the tube in. Also due to the kevlar cloth construction of the FlatAway liner they claim snakebite flats are reduced vs plastic liners, and they only weigh 32 grams vs 98 for Mt Tuffy. So if you decide on using a liner skip the nylon plastic **** and use the Panaracer FlatAway. I use them but only on my rear tires because that's where most of the flats occur anyways and don't want to waste money on the front.

Slime tubes in road bikes don't work, once the psi exceeds 70 the **** just blows out of the smallest hole, and their presta valves are cheapest crappiest valves I ever used. Thorn tubes offer some limited protection but add a lot of weight, Your first line of defense is the tire, then a liner, if something makes it past those two a tube won't stop it so just use a regular tube.