I bought some Conti Supersonics in the 650x20 size for my Rocketwing. These were going to be my race tires for 20k time-trials at Fiesta Island which is flat with a good smooth surface.

Well, I've had 2 blowouts already. The front tire blew out right after I aired it up with a CO2 cartridge. The other tire blew out after being ridden a couple miles as a back tire. It had been inflated to 160psi.

Continental says the tire can be inflated to 170psi so I'm wondering why they blew. Maybe I'm too heavy at 205lbs to use one as a back tire?

I'm putting my Michelin Ironman 650x23 tires back on for my time-trial tomorrow!

Your feedback appreciated!

Jim

yes like he said, i tend to not follow what it says on the wheel because 1) the psi rating can vary from person to person. some are heavy, some are light. these numbers should serve as your guide but should nto be followed depending on different conditions.

good luck with the races tomorrow fellow softrider

I bought some Conti Supersonics in the 650x20 size for my Rocketwing. These were going to be my race tires for 20k time-trials at Fiesta Island which is flat with a good smooth surface.

Well, I've had 2 blowouts already. The front tire blew out right after I aired it up with a CO2 cartridge. The other tire blew out after being ridden a couple miles as a back tire. It had been inflated to 160psi.

Continental says the tire can be inflated to 170psi so I'm wondering why they blew. Maybe I'm too heavy at 205lbs to use one as a back tire?

I'm putting my Michelin Ironman 650x23 tires back on for my time-trial tomorrow!

Your feedback appreciated!

Jim
I ride these tires size 23 on 700 wheels. I weigh 210lbs and run 120 front 125psi rear with no issues. No advantage to pump your tires to 160 IMO. Many wheels also have a psi limit under the rating of the newer open tube design tires

I bought some Conti Supersonics in the 650x20 size for my Rocketwing. These were going to be my race tires for 20k time-trials at Fiesta Island which is flat with a good smooth surface.

Well, I've had 2 blowouts already. The front tire blew out right after I aired it up with a CO2 cartridge. The other tire blew out after being ridden a couple miles as a back tire. It had been inflated to 160psi.

Question - did they blow OUT (casing burst), or did they blow OFF (became unseated from the rim). These are two very different things. Blow offs are most frequently a result of improper installation, or occasionally from overheating (as during extended braking on steep downhills). Tire maximum pressures are usually rated conservatively, and are usually about about half of the test blow off pressure. If the tire was inflated at or below maximum pressure and the tire blew off during installation, or just a few miles after installation, I'd bet it was due to improper installation.

You want your pressure to be under the wheels maximum pressure while also remaining under the maximum pressure for the tire.

The front tire blew out right after I aired it up with a CO2 cartridge. The other tire blew out after being ridden a couple miles as a back tire. It had been inflated to 160psi.

I've the same question than Mark McM. Your post title and the quote above imply that the tire casings ripped, meaning that your Conti Supersonics are now trash. Am I right in assuming this - or did the tubes blow out and your tires are OK?

I bought some Conti Supersonics in the 650x20 size for my Rocketwing. These were going to be my race tires for 20k time-trials at Fiesta Island which is flat with a good smooth surface.

Well, I've had 2 blowouts already. The front tire blew out right after I aired it up with a CO2 cartridge. The other tire blew out after being ridden a couple miles as a back tire. It had been inflated to 160psi.

Continental says the tire can be inflated to 170psi so I'm wondering why they blew. Maybe I'm too heavy at 205lbs to use one as a back tire?

I'm putting my Michelin Ironman 650x23 tires back on for my time-trial tomorrow!

Your feedback appreciated!

Jim

I tried these when they first came out, about 4-5 years ago. Yes, they blew off my rims several times, when inflated close to their max pressure, too. I'd keep them down around 130 or less; they didn't blow off at that pressure.

The rim can make a difference. Some hold tighter than others.

In any event, these are the most flat prone tires I've ever tried, by far. I don't think I got a single ride in without a flat. They just weren't worth it.