Conti Supersonic tires keep blowing out!

[jshelton]

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

 

[jimmer23]

I used these last season as my training/race tires believe it or not. At 185, I had only one blowout. The tires are fast and light, and as a result they also puncture and blowout easily. Durability is not it's strength, get some Conti Attack/Force tires and you'll be happier. They're a little thick (22F/23R) but weigh only slightly more than the SuperSonics. Not a problem all season with them.

 

[gclark8]

Do Conti make the Attack/Force tires in 650c??

I am buying TT/Tri tyres next week and had it down to GPs and Gator Skins...

 

[jimmer23]

Do Conti make the Attack/Force tires in 650c??

I am buying TT/Tri tyres next week and had it down to GPs and Gator Skins...

Ah shoot, I didn't read carefully enough sorry. You're right to try just the regular Grand Prix then - they come in 650cc size.

 

[John M]

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

What kind of wheels are you using? Mavic clincher rims are rated to 146 max PSI with a 19mm tire, 138 with a 23mm, Zipp at 125 psi. Probably more of a liability issue on the manufacturers part rather than a performance issue, but under real-life riding conditions on roads that are not as smooth as velodromes, 115-120 PSI is plenty. However, if you really want to go super high-pressure, go with tubulars.

See this link for a longer discussion of the issue of PSI limits and high-performance clincher wheels.

http://www.insidetri.com/train/bike/articles/1599.0.html

 

[Adam-from-SLO]

Aren't those things like 120 grams... with just about no rubber on them

Maybe for track riding/racing ......... but not out on the black top .

I'd simply go with a Conti Grand Prix 650 ........ great performance, at a fair price.

 

[jimmer23]

What kind of wheels are you using? Mavic clincher rims are rated to 146 max PSI with a 19mm tire, 138 with a 23mm

I rode the SuperSonics on my Mavic Ksyrium SCC SL's at 170psi for a full season with only one blowout. If you've ever tried to put a set on the rims, you'll see why 170 is safe - they're damn near impossible to pry into place. I think that "limit" is artifically low.

 

[domaindomain]

Crikey, thats a lot of pressure. I know its in the range but, to me, its a lot.

How about looking at Tufo tyres - clinchers that are like a tub. They pump up very hard and are ideal for time trials on good roads.

Look here for an example.

 

[gclark8]

Tonight I noticed the new Conti GP 4000 is out now and in 650c :
http://www.conti-tyres.co.uk/conticycle/ti grand prix 4000.shtml

 

[jshelton]

What kind of wheels are you using?

I'm using HED3 wheels.