[Tom_77]

This morning on the train I saw something rather unusual – a left-side drive bike. It was a BMX.

Wasn’t sure why you’d want the chain on the “wrong” side, so I asked the owner. He said when he’s grinding rails he prefers to grind with the right-side of the bike, so having the drive on the left means it’s less likely to get damaged.

Topic

[Matthew Acton-Varian]

As it is a single speed

As it is a single speed freewheel sprocket, and the inner surface is threaded throughout, you can just flip the freewheel assembly over and attach it in reverse, providing you have the tool interface on both sides. I don’t know if they use reverse thread lockrings like track sprockets to keep it secure, though.

[Matthew Acton-Varian]

The safety bicycle was a

The safety bicycle was a British invention, and the idea of the drivetrain being on the right had become standard long before motor vehicles really became a thing. The idea of specific travelling lanes wasn’t officially established until much later. It was common in the days of horse and cart for people to just ride any way they saw fit.

[ktache]

I was wondering about the

I was wondering about the ratchet going the wrong way, but if it’s quite common in BMX there must be enough of a market. Bit of DIY needed for the first one, or is it a “fairly simple” modification?

[Rendel Harris]

Matthew Acton-Varian wrote:

Because of production costs conventional gearing and commercially available products tend to revert to the default right hand side. The idea being you avoid giving your trousers the Victorian equivalent of a Cat 4 Tat when you step off as the bike leans on to your standing leg on the pavement.

Given that nearly all of Europe, China, Russia and the Americas drive on the right, so their standing leg when dismounting would usually be the right, surely the market would default to a left-side drive train if that were the reason?

[NotNigel]

Left hand drive is quite

Left hand drive is quite common in BMX.  It basically puts the drivetrain out of the way for riders who predominantly grind and do lip tricks on the right hand side of their bike.

Edit….which is what you’ve already wrote.

[Matthew Acton-Varian]

Left side drive is rare and

Left side drive is rare and has only been used in specific applications – BMX is one of them. Track cycling is another where LHD has been used. A few years ago the US Olympic squad experimented with a LHD drive bike – the thinking being that as it traverses the track on the inside, it takes the shorter distance, and therefore travels very slightly slower through the air, than on the right hand side. There was no proven benefit so the idea was dropped, although Japan’s £/$100,000 bikes at this year’s Olympics, made by Toray themselves, also featured a LH drive.

Because of production costs conventional gearing and commercially available products tend to revert to the default right hand side. The idea being you avoid giving your trousers the Victorian equivalent of a Cat 4 Tat when you step off as the bike leans on to your standing leg on the pavement.

[Author]

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