Mountain biking is the sport of riding bicycles off-road. I believe it was the actions of people in the 70s that really lead to us having the bike category of mountain bike.
During the 70s riders in California and Colorado began modifying old cruiser style bikes for off-roading. They would modify ballooned tire bikes with BMX gear like handlebars and gears and called these bikes Klunkers.
The first mountain bike
In 1978 Joe Breeze created what many believe is the first purpose-built mountain bike. There were only 10 Breezer bikes made with this first design.
1981
It wasn’t until 1981 that the big manufacturers started getting into the game. Specialized seems to be considered the first with the Stumpjumper. Univega began offering the Alpina mountain bikes also in this year. Schwinn must have been right behind because their 1981 catalog has the King-Sting and King-Sting 5 which look like early mountain bikes to me with knobby 26” tires and BMX style handlebars. The King-Sting 5 is a 1X with 5 speeds which is interesting given the popularity of the 1X drivetrain now. From the Schwinn catalog:
Equipped with Schwinn knobby gumwall tires and UKAI anodized box rims, the King-Sting 5 is a combination of durability and lightweight that is built to make off-road riding an exhilarating experience.
1982
Schwinn would add the Sidewinder and describe it as a mountain bike in the catalog. It’s funny that many sources claim Schwinn was late to the mountain bike game. From here lots of companies start getting in.

1983
Trek offers the model 850 mountain bike.
1984
Bianchi offers the Grizzly mountain bike. Cannondale offered the SM500 mountain bike.

1985
Raleigh started selling the Maverick mountain bike.
1987
GT introduces its first line of mountain bikes.

These early mountain bikes were all steel framed bikes with knobby tires and no suspension. They would go on to change quite a lot to become what we now know as mountain bikes. Here are some of the innovations that began happening with mountain bikes:
Mountain bike timeline of innovation
1984
Joe Breeze comes out with the Hite-Rite seatpost. This allowed riders to raise and lower their seat while riding. The first dropper post.
1990
Doug Bradburry the founder of Manitou built the first mountain bike suspension for in his garage. It was just a spring with no dampening.
1991
Front shocks start showing up on mass market mountain bikes.
1992
The Gary Fisher RS-1 is one of the first successful full suspension mountain bikes.

1997
Hayes comes out with the Mag disc hydraulic brake.
1998
Trek offers the 8900 mountain bike with hydraulic disc brakes.
1999
Tubeless bike tire options start coming to market.
2002
Surly offers the 29” tire Karate Monkey and begins bringing bigger tires to the masses.
2005
Surly offers the first mass market fat tire bike, the Pugsley. Most fat bikes use tires almost 5” wide!

2007
27.5” tires start being used on mountain bikes. A compromise between 26” and 29”.
2010
Frame geometry really begins changing. It takes years, but eventually top tubes become more angled, headtube angles change, bottom brackets are lowered…. Stems would become shorter and handlebars wider.
Thru-axles start replacing quick release skewers. They are much better for the powerful hydraulic disc brakes.
2012
Shimano comes out with a clutch-type derailleur the XTR Shadow Plus.

Frame material: Frames have changed from steel to aluminum and now to carbon for the most expensive bikes.
Gearing: The 1981 Stumpjumper had 15 speeds with a 3×5 drivetrain. Speeds maxed out around 2010 with 27 speed 3×9 drivetrains. 2x drivetrains would then move in with the 20 speed 2×10. Now the most expensive mountain bikes are using 12 speed 1×12 drivetrains. Quite a roller coaster ride of gearing.
Mountain bikes are now about 25% of the market, and the most popular type of bike. What will the future hold?

Interesting overview and it’s really a fascinating development. It’s odd though that gravel bikes somehow tap into the gap between road bikes and modern MTBs, which the early MTBs filled. One can’t forget that the first races such as TdF were run on primitive roads and gravel tracks, something which Strade Bianche and Paris-Roubaix tap into – perhaps off-road riding was always an essential characteristic of cycling.
It’s an interesting evolution. Looking at old catalogs they all changed from mostly road bikes to mostly mountain bikes. I guess people wanted to travel far and fast over rougher terrain and we got gravel bikes.
True, it does make sense – it seems that when most people buy a bike for casual riding, they always seem to go for an MTB, even if it will never see dirt. A road bike with 28mm tyres is however far more capable in 99% of its likely uses. Gravel bikes might just fit the new niche.
Yeah I’ve known a lot of people with mountain bikes that never see dirt. Many would probably best be served with some sort of comfort cruiser.
I remember early mountain biking when it was basically barreling downhill on an old single-speed cruiser. There was a famous descent on Mt Tamalpais ((home of most of the early mountain bike crowd like Joe Breeze, Charlie Cunningham, Tom Ritchey, Gary Fisher, et al) called “repack” because they would heat up their rear hub enough to melt the grease and need to repack it after a single descent. The late Bruce Gordon foresaw the gravel bike when he built his “Rock ‘n’ Road” starting in 1988.
I think this is what inspired Joe to make the Breezer.
I live in San Francisco for the present time. There are high hills and slopes. I need a bicycle that is up to the challenge.
Urban biking in San Francisco is pretty fun. I’m not sure if it’s the bike or the rider that has to up to the challenge. Try riding up 17th St from Castro and then up and over Twin Peaks. Maybe the prettiest ride one can do and stay in a major city.
Sounds like a plan and a gorgeous ride! Thank you 🚲 🚲 🚲
Saw a video of one of those klunker rides a while back. Think it was posted by Jim on Fit Recovery? Those guys were insane! 😆
I’ll have to try to find that.
Interesting stuff!
Thanks
I miss mountain biking! I thought when we moved to California from central New York that the nice weather here would mean more riding, but it turns out I only really like to ride my mountain bike in the woods, and woods are in relatively short supply around here …
I mostly ride in the woods.
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