Saturday, November 12, 2016

1992 / 93 Bradbury Manitou FS

Most fans of vintage mountain bikes are familiar with the Answer Manitou FS series of bikes. Built under license from Doug Bradbury starting in 1992 it was one of the more iconic bikes of the 90s. Fewer people will know that prior to Answer building the Manitou FS Doug made a small batch of these bikes out of his Colorado Springs shop. Made by hand and carrying many of the custom features developed on his hard tail bikes the Bradbury made Manitou FS is quite a unique machine!

Starting with the first prototype in 1991 Doug built approximately 60 of the FS bikes culminating in a small batch in 1993. I believe that the bike featured here is one of those last ones built in 1993 and represents the culmination of the design. You can see my writeup on the original prototype here : The main difference between the Answer made bikes and the Doug made ones is that like his hardtail frames they use a 145mm rear hub with an asymetrical rear end to enable the bike to use a dishless rear wheel. The front fork on this particular bike is a somewhat customized Answer Manitou 2 (Doug stopping making forks in 92) with 105mm hub spacing and a Titanium threadless steerer.

If the 90s era of mountain bikes was defined by CNCd components then this bike is the poster boy for the generation. Aside from the Shimano parts, the tires, seat and grips virtually every single component was made on a CNC machine.

Offset rear dropout required to fit the massive 145mm rear wheel.

Shimano M900 rear hub spaced out to 145mm using a custom made spacer pressed onto the hub flanges and a tandem rear axle.

Doug was well known for making stems for his bikes starting way back in 1988. The vast majority of the stems were the 1" quill version transitioning to 1 1/4" in late 1991 as he started using Easton tubing. At the very end of the run he made a handful of threadless versions of the stems, but for the most part they never really made out into the hands of the customers. This is one of three stems he had hung onto, and was built for this specific bike and fork combination. A rare piece indeed!

Unfortunately these and the later Answer made bikes were very prone to cracking, especially at the headtube. While ultimately this was a attributed to the strength of the Easton Variolite 7005 series tubing, exacerbated by too tight of a tolerance between the headtube and headset. In order to preserve this brand new frame I reamed out the headtube to create a 0.003" interference fit for the Chris King headset. As the bike was made interference was closer to 0.018", which when you think about would put tremendous load on the thin headtube and helps explain why some of these bikes were inexplicably cracked although they were never actually ridden!

Unlike the earlier 91 and 92 Easton made frames from Doug the late 92 and 93 made frames do away with the gusset at the head tube and top tube junction.

While I debated putting an original Bradbury made fork on this bike, Doug had selected this actual Answer Manitou 2 fork for this bike. Both the frame and fork (and stem actually) were labeled with the name of the French distributor for whom this bike was built, but never delivered. So, I decided to keep it as it was intended. Ultimately I found a custom made hub that fit the fork perfectly and so the entire package is as it was meant to be.

Custom made Manitou front hub spaced to 105mm to fit the custom Manitou 2 fork.

The upper rear pivot on the Doug made bikes is smaller than the production Answer bikes. Both use a Delrin bushing with a Stainless Steel sleeve, but the Doug made bikes have a smaller OD sleeve. The upper swing arm brace on this bike is a jewel of a machined piece. Fully hogged out of a solid piece of Aluminum billet it is represents the pinnacle of the design and is virtually identical to the production Answer made bikes. 

If it wasn't fully obvious the rear suspension on this bike is literally a Manitou fork with pivots swapped in for dropouts and a different crown that enables the assembly to pivot. The internal elastomer stack is virtually the same as fork, just a little bit shorter. The rear derailleur cable goes through a slot near the brake boss and then through a movable cable guide at the lower pivot location

The lower pivot and swingarm are also the most advanced versions of Doug's design differing from the earlier concepts by the degree of machining used for weight reduction.

Keeping up with appearances the cockpit is full of CNCd goodies from Grafton including Speed Controller brake levers and shifter perches used to mount the M900 XTR shifter pods.

The list of CNCd parts continues with a custom front derailleur clamp for the Shimano XTR front derailleur and a massive 31.8mm seat post with a head out of a Ringle Moby post.

There just are no bad angles for this bike, and I for one do not get tired of looking at photos!!

Growin up I had a poster of the first generation of the Answer Manitou FS hanging up in my room. That was T-H-E bike to have and at the time it seemed beyond unobtainable. Thinking back I didn't even think Doug made more than a couple prototypes of the design and to this I've only ever seen two to three of these in the wild. So, it's simply a dream come true to have had the opportunity to work on this project and be able to be able to hold one of these bikes in my hands. While this bike is not staying with me I am working on restoring the original prototype and hope to be able to put some miles on that bike!

No comments:

Post a Comment