San Francisco's cable cars are all going out of service for ten days next month as part of a gearbox rehabilitation project — and anyone coming to town and hoping to take a ride on one will be sorely disappointed, and offered a bus ride instead.

Yes, the SFMTA will install buses at cable car turnarounds starting on September 13, which absolutely no one will want to use. And as the Examiner reports, all three cable car lines have to be shut down for the ten-day project because it involves the "master cable" at the main Hyde Street gearbox.

The gearbox rehabilitation project has been ongoing for two years, and it's the first time that such an overhaul of the cable car system has occurred in over 30 years, since 1984. Each cable car line has been shut down individually as the 35-year-old gearboxes have gotten replaced, beginning with the California Street line in September 2017 — a $6 million project in all.

There's a total of 12 miles of cable running underneath the streets to pull the cable cars up and over hills, and as you can see in the video below, each of the five gearboxes is huge — the size of a car — and they're attached to even larger wheels.

The cable cars will come back into service on September 23.

Meanwhile, before that, it's Muni Heritage Weekend starting September 7, in which transit nerds come from all over to get to ride in historic buses and streetcars. Also, that's the weekend that this oldest cable car in the system, #19, is going to come back into service after a 77-year break.

Photo: SFMTA/Instagram