I was in the middle of my last set of Xalibu+4 when there was a huge bang and all of sudden my rear flatted and the tire was half blown off.
What do you think happened? It was literally right after the big 30 sprint and going into the first of the 8x15s surges, last set of 7.
Also fell for this.
The heat build up blows it out. Have also had the same thing happen IRL descending a particularly steep road in the Alps.
What pressure range did you run, relative the max for the tire?
Looks like you had a proper side tube and not a smaller one that was over-stretched.
You might consider pointing a fan towards your rear wheel. I did on for omnium to reduce noise but it should also help with this.
How does that reduce noise?
I had it pumped up to just under 80psi. The max is stated as 116psi (Conti Grand Prix 5000).
I actually do have a fan behind me but it is kind of pointing upwards towards my butt rather than the rear wheel. I can totally believe this being heat-related.
So I guess this means I can’t blame the combination of Xalibu+4 and my humongous power output?
That seems low pressure for use on rollers, unless you are quite light.
You typically should run higher pressure to reduce tire casing deflection. That extra flex is what lead to much higher temperature and may be the reason for the failure.
I’d consider 100psi a minimum for roller use on a 25mm tire (what size is yours?).
Good point! My tires are 28mm. My air compressor only goes up to 85psi, so I’ve never inflated above that. Is that bad?
My reasoning might be flawed or not apply on this particular case, but it is like this. All the watts we output must go somewhere. Some of that energy becomes heat and other become noise. The only way to reduce the sound produced is to increase the amount of heat produced, which we can increase by actually removing heat from the system.
Now, it might be that the such effects cannot be applied directly to a bicycle on a trainer or that the effect is minimal, and the reduced noise I notice is just placebo. But at the very least, I’m reducing the tire wear .
Maybe not bad exactly, but it could be the cause of your tube failure. As mentioned above, the tire conforms around the roller drums. At low pressure, that means the tire flexes a LOT. That flex leads to friction and heat. Excess heat could be the reason for the tube failure.
A higher tire pressure will reduce tire flex on the roller, and should reduce tire heat as a result. If the excess heat blew the tube, higher tire pressure may keep temps to a safer level for the tube.
I’d suggest considering a regular hand floor tire pump that allows you to get pressures around 100psi.
And just to confirm, latex vs butyl is not part of the problem?
Maybe. I’ve seen people blow out butyl tubes on rear wheel trainers too. Sometimes from underinflated pressure.
So a “regular” tube can blow in poor conditions too.
Latex is generally more heat sensitive, but I blew a butyl tube years ago on a wheel on trainer during a sprint. I’d wager that would happen more readily with latex, but no proof. (When I rarely run my wheel on trainer anymore, I have a Conti home trainer tire on which doesn’t generate much heat at all.)
This is not how it works.
You don’t reduce the amount of sound by increasing the amount of heat. It’s not a balanced equation. And you also don’t create more heat just because you remove more. You just cool the whole system down.
But yeah, keeping the whole system cooler will help with heat effects, maybe even prevent blow outs like the OP had! So it’s not a totally bad idea, just not for the reasons you’ve stated.
just checking if anyone else has experienced any issues with latex tubes and rollers? it seems that the OP was using metal drums? I’m planning on buying a set of elite nero/quick motion rollers and wanted to see if there were any issues using latex tubes on them.
I use the Feedback Sports rollers and haven’t had any issues with latex tubes. I’m too lazy to swap them out, and they’ve held up so far. I make sure to pump my tires up way more than usual, too. I run around 60-70psi normally outside butt will go up to 100+ for the rollers.
I just blew out a butyl tube in a 23mm GP5000 on my Kickr Snap a few weeks ago. I usually run 110psi and must have went to long without topping the psi off because I’m convinced it happened because of low psi. I could see the tire must have been flexing enough to create a week spot and heat combination enough to blow. In my case the tire actually ripped. I’d recommend 100-110psi. This is when a spare wheel is ideal so you can run a dedicated wheel, tire and tube for indoor.