The heat has brought out a new plague of mad, show-off, kamikaze-style boy cyclists. I have never been all that keen on cyclists, ever since the dog was mown down and I was nearly sliced in two on the pavement, but compared with this new lot, the old-style cycle maniac is Fotherington-Thomas.

The latest sort tend to come out on warm evenings and have a new type of bike – minimalist, no gears, no lights. Bare-chested, or with shirts billowing in the wind, they swirl and wheelie about, across red lights, the wrong way up one-way streets, along pavements – no bells, no helmets, no fluorescent jackets. None of that cissy stuff, just top-speed, miss-death-by-half-a-whisker freestyle riding.

“They’re all boys, aren’t they?” says my friend Olga breezily, “That’s what they do. Give them any sort of vehicle and they’ll try and kill themselves in it.” She rather admires them, because she’s a cyclist herself. I had a terrific row with her in the car last week, me driving along in the dark, a whirling mass of shadowy boy cyclists weaving and zipping round the cars and hovering in blind spots, while Olga applauded them and admitted shooting red lights, nipping up one-way streets and along pavements herself.

“I’ve got every right to do it,” said she saucily. “There are no proper cycle lanes and those one way systems are terrifying. You all drive much too fast. The only safe place for cyclists is on the pavement.”

I had a shout, but Olga didn’t give a stuff. Last week a crazed motorist cut her up, called her a lesbian, and drove on to the pavement, trying to kill her. And Fielding had to jump off his bike and hurl himself into a hedge just before a mad motorist crushed his bike to pulp, on purpose.

There’s no arguing with Olga and Fielding. To them, it’s clear cut: cyclists green and good, motorists bad. They know they’re right. But I know I’m right. This is another war with no solution in sight. Let’s hope there aren’t too many casualties.