Drift Tengoku — October 2013

Where is the air leaking from? The valuable front tires still had plenty of tread and were high-grip tires. He said he filled them in the morning, but by evening they were flat. It was a slow puncture. I asked, ‘Maybe the bead was damaged when it was mounted?’ He said, ‘I didn't mount them myself…’ Well, we'd find out by looking. First, I inflated the mounted tire to 4 kg/cm² and checked for leaks. Leaving it for about 15 minutes didn't show any change. Next I ran water around the gap between the bead and rim to see if bubbles appeared…

I checked whether bubbles appeared as I ran water around the bead. Nothing seemed wrong. So I decided to remove the tire, but Tsukamoto was worried about doing the job. ‘I could cut the bead while removing it, right?’ he said anxiously. That's possible if you're careless, but if you worry about that, you can't modify anything. It's only a tire, and not even an unusual size. Ignoring his hopeful look that I would do it for him, I had him remove it himself.

With the bead broken down, Tsukamoto carefully inspected the tire. After a while he said, ‘Ah! Isn't it right here?’ and found a tiny cut in the bead. It looked so small that it might not matter, but since nothing else was wrong, that had to be the cause. Covering it up with bead sealer… ‘What should I do about this?’ he asked sadly, so I had to help. I handed him some bead sealer from the garage's stash…