Originally Posted by
Litespeed
Our tire size is 700 x 28 Continental Gator (Duriskin) Skin with 700 cc Velocity Dyad rims. We keep the pressure at 100. It looks like a tear in the sidewall, not an actual cut. Do you guys carry a foldable tire with you when you ride? We have had a blowout on the sidewall once before about 3 years ago.
The Gatorskins actually have a pretty good reputation and seem to do a pretty good job of balancing durability with performance. A more robust tire like the Panaracer Pasela might be a bit more resistant to the occasional road hazard / puncture threat, but not feel as lively as the Gatorskin.
As for tire pressure, the three things that I use to guide how much to run in a tandem tire are:
1. What's the manufacturer's maximum recommended pressure (Conti's is 116 for your tires)
2. How much tire pressure do I need to put in a tandem's rear tire to get the right shape, e.g., just a slight bulge when both riders are sitting on the tandem. If the tire looses 1/2 of it's sidewall height, then there's not enough tire pressure and the risk of pinch flats and sidewall punctures is increased dramatically. If there is no bulge, you lose some comfort and also increase rolling resistance on roads with less than perfectly smooth surfaces, e.g., chip seal, concrete, weathered asphalt.
3. What works best for you and your stoker? Running a tandem's tire at or below the "normal" recommended psi is often times a bit too low given the extra weight that a tandem carries. Even though you may only weight 110lbs, the rear wheel is carrying all of your weight and about 1/2 of your captain's weight given where the center of gravity falls on a tandem with two average size riders. Therefore, running at 100psi may or may not be enough for your team IF it doesn't give your tire the proper shape. Given that you are reporting a higher than average number of sidewall punctures and now a sidewall tear, I would suspect that -- absent a mis-aligned brake shoe rubbing against the tire or road hazard -- you probably should be running your tires with something closer to the 116 max psi. It would also be a good idea for your captain to look at where he's positioning the tandem on the road. If he tends to ride very close the shoulder where all of the road debris collects, flats will be a much more common occurance than if you rode right at the fog line or along the right track of the traffic lane when there is no fog line as those areas are almost always swept clean of road debris.
As for us, as mentioned in several other posts on tire topics, we've used the same brand and model of narrow foldable racing tires for the past decade, in one of two different sizes -- 700x23 or 700x25 -- inflated to 135psi and 145psi, respectively. Our total team weight is about 275-285lbs, depending on the time of year. I don't want to jinx myself, but we have very few flats and the occassional flat that we do have clearly comes from something that comes through the tread, not the sidewall. We usually have a spare foldable tire on the bike, strapped under the stokers stem/my saddle when we participate in century rides, rallies or tours and it's often times on there even for our local rides if I don't bother to remove it between events.