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anthonybkny 10-14-13 10:30 AM

Keep getting flats
 
So i purchased a set of Continental Grand Prix 4 seasons about 500 miles ago, and have had 2 puncture flats so far. Both rear tire. Previously i had on thickslicks, without a single flat. The first puncture was a shard of glass. The second puncture was either a piece of a branch of a nut shell, hard to tell, but it punctured the tire and through the top and bottom of the tube. Keep in mind, im a clyde. im about 240lbs right now. Also, i keep the rear tire pressure at 115lbs. Is it just bad luck or do i need a more puncture resistant tire? Id like to stay with a lighter weight tire if possible if i need to make a change.

jowilson 10-14-13 11:00 AM

Sounds like just bad luck, but a through and through puncture has only happened once with me. An inch long nail stuck through the tire casing, tire liner, and tube. It flatted and the nail pushed through further. Maybe get a higher TPI tire, or a wider tire. What size do you have currently on the bike?

anthonybkny 10-14-13 11:06 AM

Quote:

Originally Posted by jowilson (Post 16159773)
Sounds like just bad luck, but a through and through puncture has only happened once with me. An inch long nail stuck through the tire casing, tire liner, and tube. It flatted and the nail pushed through further. Maybe get a higher TPI tire, or a wider tire. What size do you have currently on the bike?

thanks for the reply. 700x28

jowilson 10-14-13 11:15 AM

Quote:

Originally Posted by anthonybkny (Post 16159792)
thanks for the reply. 700x28

Maybe try some 32's or 35's. They can support more weight at the same psi. With 32's you can probably drop down to 100 psi and be fine.

10 Wheels 10-14-13 11:18 AM

Quote:

Originally Posted by anthonybkny (Post 16159792)
thanks for the reply. 700x28

Flats to me are just Luck.

I had more flats on 35's then any other size.

Run 28's on a touring bike and one road bike.

CommuteCommando 10-14-13 01:37 PM

Roll the dice. Bike tires are thinner than car tires. Period. They will go flat more often. I accept the possibility, and curse the reality when it happens. Then I fix it. So it goes.

ThermionicScott 10-14-13 02:35 PM

Since these are not pinch flats, we can rule out tire pressure and clydesdale status. It's just bad luck in your case -- maybe more flat-resistant tires would help.

greenteei89 10-15-13 02:03 AM

I used to get alot of flats too... I think its really just luck. Maybe you should try a more durable tire like gatorskins?

Blue_Bulldog 10-15-13 06:56 AM

I used to get flats on the regular, to the point I was carrying a bottle of Slime, patch kit, and spare tube in my bag. I became a flat repair on the side of the road ninja. However that got old in a hurry.

When I was training for my century, the owner of the LBS that was sponsoring us looked at my tires, said "I've just the thing for you, bro." He switched me to a very very thin tire (thin compared to what I was using) that was almost like a road bike tire, and was one of those 100psi+ high pressure dealies.... and then ran a tire liner through it and put self sealing tubes in there.

Not a single flat since.

(watch me just have cursed myself)

anthonybkny 10-15-13 08:39 AM

thanks for all the feedback guys. im gonna stick it out with the 4 seasons, i think its just luck also. but if i get flat any time soon, then im stickin a gatorskin on the rear

dwinks 10-15-13 10:09 AM

Wider, lower-pressure tires, all other factors being equal, will get far less flats than narrower, higher-pressure tires. A flat occurs when an object is pressed against the tire with greater force than the tire is able to withstand. Wider, lower-pressure tires will be able to deflect more when running over an object, exerting less force downward upon whatever you ride over (as there's more area supporting your weight, so less weight per area). Often the downward force is less than the amount of force required to push said object through the tire, and you simply roll over the object and continue on your way. If you ride narrower tires, they require higher pressure, and thus have more weight per area pressing down, which greatly increases the chances of pressing down on an object with enough force to push it through the tread.

Contrary to what some of the above posters claim, your weight absolutely has everything to do with getting flats. For an example, imagine pushing your bike, without any panniers or anything else weighing it down, over a huge field of super sharp glass. Since there's almost no weight pressing down on the tires, it's fairly reasonable to expect the bike to suffer no flats from this. Now hop on and ride over the glass. It would be very reasonable to expect a flat in short order due to the weight on the tires pressing down onto the glass. An unloaded biking being one extreme and a loaded bike with a clyde being the other. A lightly loaded bike with a lightweight riding would be somewhere in the middle, and with the same bike, same tires, same conditions, the lighter rider would have far fewer flats.

Assuming you don't buy some 1000+ gram POS tires, wider tires don't even slow you down, as the wider tires have LESS rolling resistance than narrow, an extremely negligible increase in air resistance, and decreased suspension losses (energy/speed lost to 'road buzz' and other vibration, which is a huge factor in speed). Narrow tires have a weight advantage, which outside of extremely competitive (think constant attacking) riding, means absolutely nothing, and for the average rider, the lower suspension losses of a wider tire far outweigh the penalty from slightly higher rotational inertia. So overall, wider = faster, provided your wider tire is a quality tire, and not some $12 POS knobby from Wallyworld.

Not only do you get a very noticeable decrease in flats with wider tires (especially if you're a clyde), an increase in speed in 99% of riding situations, but wider tires are just more comfortable and safer. Basically a win-win-win.

Slap the widest tires on there you can fit, with moderate flat prevention (don't go overboard on flat prevention tires, or they'll be dog-slow), and you should see a drop in flats. Even if you get tires with the exact same tread thickness, construction, etc as the ones you have now, but simply wider and lower pressure, you'll get noticeably less flats. The key is keeping the PSI low, as higher PSI does nothing other than make the ride slower, less comfortable and much more likely to hammer debris through the tire rather than deflecting and rolling over it.

I've had pretty good luck with Michelin City tires with "ProTek" myself. One flat in the last 4,000 miles, which was from a large, pyramid shaped chunk of glass on a rainy day. Had it been dry, it probably wouldn't have flatted even on that, but the water lubricates the glass, dramatically increasing the chances of it penetrating the tire.

squegeeboo 10-15-13 10:40 AM

I'd suggest tire liners. I run mr tuffys under whatever kevlar bead tires are cheap when I need a new pair. Get about a flat a year. The 1 year I got talked out of mr tuffys by the LBS, I was getting over a flat a month on average.

fietsbob 10-15-13 10:59 AM

Spend more money and you get tires with puncture protection features under the tread,
within the tire casing .

tires like Schwalbe marathon plus - green guard include a tire liner in them , and are seamless.

tire liner strips, added, have an overlap, and the end of the strip can wear a hole in the tube, over time.

Andy_K 10-15-13 11:07 AM

Quote:

Originally Posted by greenteei89 (Post 16161812)
I used to get alot of flats too... I think its really just luck. Maybe you should try a more durable tire like gatorskins?

I'm not convinced that Gatorskins are more durable than GP 4 Seasons. The Conti marketing material isn't clear on this point, but it seems to me like Vectran is better than PolyX.

I wonder if OP wouldn't have more luck with slightly lower tire pressure. I'd say 115 is awfully high for a 700x28. I weigh around 200 pounds and run my 700x28 GP 4 Seasons at around 90 psi.

anthonybkny 10-15-13 11:13 AM

Quote:

Originally Posted by Andy_K (Post 16162724)
I wonder if OP wouldn't have more luck with slightly lower tire pressure. I'd say 115 is awfully high for a 700x28. I weigh around 200 pounds and run my 700x28 GP 4 Seasons at around 90 psi.

i was thinking this also, im gonna run the rear at 100 psi and see how it goes. thanks

anthonybkny 10-15-13 11:14 AM

Quote:

Originally Posted by dwinks (Post 16162594)
Wider, lower-pressure tires, all other factors being equal, will get far less flats than narrower, higher-pressure tires. A flat occurs when an object is pressed against the tire with greater force than the tire is able to withstand. Wider, lower-pressure tires will be able to deflect more when running over an object, exerting less force downward upon whatever you ride over (as there's more area supporting your weight, so less weight per area). Often the downward force is less than the amount of force required to push said object through the tire, and you simply roll over the object and continue on your way. If you ride narrower tires, they require higher pressure, and thus have more weight per area pressing down, which greatly increases the chances of pressing down on an object with enough force to push it through the tread.

Contrary to what some of the above posters claim, your weight absolutely has everything to do with getting flats. For an example, imagine pushing your bike, without any panniers or anything else weighing it down, over a huge field of super sharp glass. Since there's almost no weight pressing down on the tires, it's fairly reasonable to expect the bike to suffer no flats from this. Now hop on and ride over the glass. It would be very reasonable to expect a flat in short order due to the weight on the tires pressing down onto the glass. An unloaded biking being one extreme and a loaded bike with a clyde being the other. A lightly loaded bike with a lightweight riding would be somewhere in the middle, and with the same bike, same tires, same conditions, the lighter rider would have far fewer flats.

Assuming you don't buy some 1000+ gram POS tires, wider tires don't even slow you down, as the wider tires have LESS rolling resistance than narrow, an extremely negligible increase in air resistance, and decreased suspension losses (energy/speed lost to 'road buzz' and other vibration, which is a huge factor in speed). Narrow tires have a weight advantage, which outside of extremely competitive (think constant attacking) riding, means absolutely nothing, and for the average rider, the lower suspension losses of a wider tire far outweigh the penalty from slightly higher rotational inertia. So overall, wider = faster, provided your wider tire is a quality tire, and not some $12 POS knobby from Wallyworld.

Not only do you get a very noticeable decrease in flats with wider tires (especially if you're a clyde), an increase in speed in 99% of riding situations, but wider tires are just more comfortable and safer. Basically a win-win-win.

Slap the widest tires on there you can fit, with moderate flat prevention (don't go overboard on flat prevention tires, or they'll be dog-slow), and you should see a drop in flats. Even if you get tires with the exact same tread thickness, construction, etc as the ones you have now, but simply wider and lower pressure, you'll get noticeably less flats. The key is keeping the PSI low, as higher PSI does nothing other than make the ride slower, less comfortable and much more likely to hammer debris through the tire rather than deflecting and rolling over it.

I've had pretty good luck with Michelin City tires with "ProTek" myself. One flat in the last 4,000 miles, which was from a large, pyramid shaped chunk of glass on a rainy day. Had it been dry, it probably wouldn't have flatted even on that, but the water lubricates the glass, dramatically increasing the chances of it penetrating the tire.

great info here

Leebo 10-16-13 09:28 AM

I have had good luck with the panaracer pasela tourguard in 700 x 35. They make a 32 as well. I'm 235 lbs and run them at about 55 psi front and 60 rear.


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