Travis Brown raced this custom Manitou FS on the World Cup circuit in 1992 - James Huang/Future Publishing
Though considered archaic today, the front and rear suspension on this Manitou FS was considered state of the art 22 years ago - James Huang/Future Publishing
Frame graphics were certainly a little simpler back then. In the case of this bare aluminum frame, it was just a matter of die-cut vinyl decals - James Huang/Future Publishing
Answer Hyperlite handlebars were widely considered to be the cream of the crop in 1992 - James Huang/Future Publishing
This aluminum quill stem was machined in Colorado Springs, Colorado by Manitou founder Doug Bradbury - James Huang/Future Publishing
The underside of the stem is hollowed out to save weight - James Huang/Future Publishing
Neither end had any proper damping to speak of. The knobs on the bottom of the fork legs only adjust preload on the elastomer stack - James Huang/Future Publishing
The 12-32T cassette required just a mid-cage rear derailleur - James Huang/Future Publishing
The first-generation Shimano XTR drivetrain used full-sized 26/36/46-tooth chainrings and solid forged aluminum arms - James Huang/Future Publishing
The drivetrain on Travis Brown's 1992 Manitou FS was offset to yield a zero-dish rear wheel. As a result, the front derailleur has to move further from the centerline of the bike than it was originally designed to do. Note the settings on the two limit screws - James Huang/Future Publishing
The Manitou FS was startlingly light for its time thanks in large part to its feathery Easton aluminum tubeset. But at just 11.41kg (25.15lb) as shown here, it'd still be competitively light even by modern standards - James Huang/Future Publishing
Answer Aggressor grips and Scott bar ends provide multiple hand positions - James Huang/Future Publishing
The large-diameter, thin-walled tubes required a custom machined Ringlé seatpost head to be bonded to the oversized aluminum shaft. Cable routing was a bit of an afterthought - James Huang/Future Publishing
The rear 'crown' is aggressively machined to reduce weight - James Huang/Future Publishing
Most Manitou FS frames eventually suffered from cracked head tubes and this example is no different. We counted no fewer than five cracks, including a long one on the upper side - James Huang/Future Publishing
Shimano XTR cantilevers are still prized today for their adjustable pivots, the low-profile design, and (relatively) powerful braking - James Huang/Future Publishing
Any modern suspension engineer would immediately conclude that this low-pivot design would produce appreciable squat under power but the concept was still in its infancy 22 years ago - James Huang/Future Publishing
While the main tubes were made by Easton, Manitou preferred to use square-profile tubing for the chainstays - James Huang/Future Publishing
The simple pivot design used composite bushings and press-fit hollow steel axles. The bottom bracket is longer than what Shimano would normally have specified for XTR in order to offset the chainrings to the driveside - James Huang/Future Publishing
Production Manitou FS frames used cut-out aluminum dropouts but this prototype instead used solid plates - James Huang/Future Publishing
Ringlé anodized aluminum bottle cages were must-have items back in the day - James Huang/Future Publishing
No one produced a suitable hub for the custom 145mm-wide rear end so Doug Bradbury cut a stock Shimano XTR hub in two, then pressed the spoke flanges on to a custom-turned aluminum body - James Huang/Future Publishing
A closer look at the simple - but effective - suspension pivots - James Huang/Future Publishing
Early Shimano XTR cassettes had cogs that were individually bolted on to an aluminum spider. Later versions would instead use more durable riveted construction - James Huang/Future Publishing
Travis Brown used a Specialized Ground Control Extreme S rear and Mitsuboshi Hilltop 5100 front tread, both marked as a modest 1.95in width - James Huang/Future Publishing
Both hubs still bear UCI stickers that were intended to prevent racers from secretly swapping out equipment mid-race - James Huang/Future Publishing
Ritchey rims were used front and rear - James Huang/Future Publishing
While the seatstays are symmetrically positioned relative to the frame's centerline, the drivetrain was offset outward to yield a zero-dish rear wheel - James Huang/Future Publishing
A single-lip rubber seal - the same type Manitou used on its forks back then - helped keep water from seeping down into the frame. Given the oversized frame tubes, the seatpost collar had to fabricated from scratch - James Huang/Future Publishing
Easton built its reputation on its lightweight aluminum frame tubing - James Huang/Future Publishing
You didn't think full-suspension XC bikes were only recently being raced at the top levels of the sport, did you? This month's Throwback Thursday feature, a 1992 Manitou FS, is more than 20 years old, but it's still in original condition – and offers a stunning snapshot of the early days of mountain bike full-sus technology.
The idea of a full-suspension mountain bike was still in its infancy back in the early 1990s but that didn't stop Manitou founder Doug Bradbury from making one that could keep up with the best hardtails of its day. The simple design mimicked the basic profile of rigid frames but with reconfigured suspension fork legs in place of the usual seat stays, plus the requisite pivots behind the bottom bracket shell, above the dropouts, and up at the seat cluster.
The minimal travel, basic elastomer internals, primitive seals and simple pivot designs might not fly by modern standards but back then, it was not only state-of-the-art but an object of lust for mountain bikers worldwide. Even just a couple of inches of travel felt like a couch compared with fully rigid machines, and Bradbury managed to provide that with minimal weight penalty thanks in part to the then-revolutionary Easton Vari-Lite ProGram taper-butted aluminium tubing.
Though considered archaic today, the front and rear suspension on this manitou fs was considered state of the art 22 years ago: - James Huang/Future Publishing
This particular example is no garage queen, either: it belongs to former pro – and current Trek mountain bike tester and brand ambassador – Travis Brown, who raced the Manitou FS during the 1992 season. The drivetrain is worn, there's a patina of dust and grime, and like many FS frames, the head tube is cracked (in five places).
The simple pivot design used composite bushings and press-fit hollow steel axles. the bottom bracket is longer than what shimano would normally have specified for xtr in order to offset the chainrings to the driveside: the simple pivot design used composite bushings and press-fit hollow steel axles. the bottom bracket is longer than what shimano would normally have specified for xtr in order to offset the chainrings to the driveside
"I knew Doug through [fellow Trek employee] Scott Daubert, who was a friend and training partner of mine at the time and he was riding for Manitou," says Brown. "After Worlds that year [1991], we talked again and I thought that it'd be awesome to ride for a Colorado company. Being an independent frame builder, he didn't really have the resources to go pro racing but it's what he wanted to do. He finally got funding for a race team from his Japanese importer – which is where a lot of his bikes were being sold at the time – and eventually said, 'I got a budget; let's go racing!'"
Frame graphics were certainly a little simpler back then. in the case of this bare aluminium frame, it was just a matter of die-cut vinyl decals: frame graphics were certainly a little simpler back then. in the case of this bare aluminium frame, it was just a matter of die-cut vinyl decals
As it turns out, Brown's career evaluating and developing mountain bike product started long before his days at Trek. Bradbury first provided a Manitou HT hardtail to try out for sizing, and said he could incorporate any changes he wanted into a custom design for his FS.
The underside of the stem is hollowed out to save weight: the underside of the stem is hollowed out to save weight
Brown indeed had some ideas, which included 50mm of additional top tube length relative to the stock geometry, paired with a short-for-its-day 120mm stem. Though Bradbury thought Brown was crazy at the time, the idea would ultimately work its way into the mainstream.
"It was very stable and that was something that I intentionally wanted so the bike would go straight when you were slobbering and tired."
This one-off also incorporated an extra-wide rear end with a drivetrain that was pushed outboard by 10mm to create a zero-dish rear wheel – an impressively forward-thinking concept that would resurface roughly two decades later for the fat bike market. The design necessitated a custom Shimano XTR rear hub with 145mm spacing (which Bradbury made himself), special asymmetrical dropouts, and a longer bottom bracket spindle to keep everything properly aligned.
While the seatstays are symmetrically positioned relative to the frame's centreline, the drivetrain was offset outward to yield a zero-dish rear wheel: while the seatstays are symmetrically positioned relative to the frame's centreline, the drivetrain was offset outward to yield a zero-dish rear wheel
According to Brown, the zero-dish wheel and wider spacing yielded a noticeably stiffer rear end.
"It had a lot of stiffness for that reason. [Doug] had an intuitive design sense and was willing to try things. He was a super smart dude."
Travis brown raced this custom manitou fs on the world cup circuit in 1992: travis brown raced this custom manitou fs on the world cup circuit in 1992
Special thanks to the folks at The Pro's Closet, who will soon open up a museum of noteworthy vintage bikes at their headquarters in Boulder, Colorado.
Complete bike specifications
Frame: 1992 Manitou FS w/ custom geometry and 145mm OLD rear spacing
Fork: Manitou 2
Headset: Chris King, 1 1/4in threaded
Stem: Manitou custom, 120mm
Handlebars: Answer Hyperlite w/ Scott ATNZ-LF Short bar ends
Tape/grips: Answer Aggressor
Front brake: Shimano XTR BR-M900
Rear brake: Shimano XTR BR-M900 w/ Madison Aztec pads
Brake levers: Shimano XTR ST-M900
Front derailleur: Shimano XTR FD-M901
Rear derailleur: Shimano XTR RD-M900
Shift levers: Shimano XTR ST-M900
Cassette: Shimano XTR CS-M900, 12-32
Chain: Sachs Sedis
Crankset: Shimano XTR FC-M900, 175mm, 26/36/46T
Bottom bracket: Adjustable cartridge bearing
Pedals: n/a
Front rim: Ritchey Vantage Comp, 28h
Rear rim: Ritchey Vantage Pro, 32h
Front hub: Bullseye
Rear hub: Shimano XTR FH-M900, custom 145mm OLD spacing
