Contender Ten Best of 2021: A Radical Klein Attitude MTB

Contender Ten Best of 2021: A Radical Klein Attitude MTB

Written by Contender Bicycles, on December 23, 2021

If one were to poll 100 people to see what they thought of this Klein Attitude mountain bike, I suspect that every single person would think positively. There is a lot of goodwill out there for Klein bikes, particularly their mountain bikes. That is because this Klein mountain bike - as well as his other bikes of the time - is the result of the pursuit of the best technology the era had to offer, without compromise.

This Klein Attitude is an excellent example of a dialed-in mountain bike of it's time. It uses hydroformed aluminum in a time when steel was still the go-to frame material. Alloy requires larger tube shapes to keep its stiffness, but there is no denying its performance when you look at the square-to-round chainstays that increase tire clearance. 

A Radical Klein Attitude MTB

Klein was unique at the time for using a smooth bottom bracket shell rather than a threaded shell that was conventional for the time. As a result, the bottom bracket bearings were pressed in, much as they are today. Further unlike anything else was the use of an inset headset bearing which allowed for the large alloy tubes seen here. All of this together saved weight, but also added frame stiffness that made the bike feel like a rocket in comparison to a contemporary steel frame. 

A Radical Klein Attitude MTB

Poke around and you’ll learn that Klein wanted a cockpit (handlebar and stem) setup that matched the performance of their alloy frames. The result was what they called Mission Control, a handlebar and stem that is welded together. Klein says it saves weight and improves steering precision, but this one specifically with its color-matched paint looks so heroic. 

A Radical Klein Attitude MTB

The rest of the build here isn’t as expressive as the frame and cockpit. Shimano XTR has always been a great choice, and the mechanical thunk between gears is incredibly satisfying. The Sun Mistral Chinook rims are also paired to XTR hubs, and while they aren’t anodized purple like some other rims of the era, they too are the best of the era. We’re particularly big fans of the Shimano XTR seatpost, the black anodized finish of which is easily-scratched but extremely light. 

While mountain bikes at the time were all over the place, throwing all kinds of new technologies at the wall and seeing what stuck, it was Klein that really built a fan base. Each Klein of the era had incredible attention to detail, a desire to push the boundaries of what is possible, and an eye for the provocative. We could use a bit more of that today.

A Radical Klein Attitude MTB

See the rest of the build sheet and photos below.

Frameset Klein Attitude alloy frame
Fork Klein Attitude Unicrown, aluminum
Headset Klein sealed bearing, integrated
Groupset Shimano XTR M900 3x8
Crankset Shimano XTR FC-M900, 175mm
Brakes Shimano XTR BR-M900
Gearing Shimano XTR 46/36/26t / Shimano XTR CS-M900 8-Speed cassette
Wheelset Sun Chinook 26" rims / Shimano XTR M900 hubs / Wheelsmith spokes
Tires Specialized Ground Control, 26 x 1.95"
Handlebar Klein Mission Control one-piece  - 600mm width
Stem Klein Mission Control one-piece - 140mm length
Seatpost Shimano XTR
Saddle Selle Italia Flite Ti
Accessories bottom bracket area chainstay protector

See the Contender Ten Best Bikes of 2021

A Radical Klein Attitude MTB
A Radical Klein Attitude MTB
A Radical Klein Attitude MTB
A Radical Klein Attitude MTB
A Radical Klein Attitude MTB


  • I have this bike in my garage! Owned it since the late 1990s. The only difference are the front forks on mine are suspension with original paint work. love it still

    Jess on

  • I am looking for a Klein – 2002 Attitude, aluminum, open frame, internal cable routing. Rockshox Duke XC 80mm, Shimano Deore LT/XT, blue/purple – could be a year earlier or later, thanks

    karen on

  • In 1990 I was 18 yrs old and financed my first Klein. So glad I did. I bought another in 1997. These bikes seem to egg you on to finish first! 3 years ago I bought a mint NOS 18 inch Klein frame and fork (Bright Red fluorescent). My build is all NOS. XTR,Ringle hubs,Campagnolo K2 rims, Polished Cooks Bros Racing cranks and much more. So far $11,000.00 invested completion date 7/4/23 Looks better than new! I will enter it in shows and cruise it on special days.

    Chris De La Cruz on

  • I have an early Klein Attitude with mitered forks that is in 95% great original shape. I also have a Klein Quantum 2 in great shape, and several other nice Kleins. I love them all.

    Mac McCarter on

  • Mike, cool bike! Glad to see another survivor.

    Alvin - Contender Bicycles on

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