Dan Priest’s 1994 AMP Research B3
AMP Research B3
A great old mountain bike from Austrian industrial designer Horst Leitner’s company, AMP Research. Horst had been working on the problem of chain torque and its effects on motorcycle suspension since the 1970s. In the mid ‘80’s he built a suspension mountain bike that used a type of four-bar linkage that would later be dubbed the “Horst Linkage”. A Horst Link has a fixed seatstay with a rear pivot below and forward of the rear axle on the chainstay. It’s a design seen in many suspension bikes today, one that uncouples braking and chain tension from rear suspension movement.
Besides the rear suspension, when given a clean sheet of paper and a chance to design a mountain bike from top to bottom, you’re looking at what Horst came up with.
The most interesting bit about this bike has to be the unusual fork. Using that little linkage at the top, the fork moves similarly to a traditional telescoping suspension fork. There is a coiled steel spring just under the steerer tube, and then the rebound damping is handled by a little through-shaft shock absorber on the side of that little linkage.
Amp fork
Oval downtube, reinforcing gussets
Rear brake
Shock close up
Amp front brake
The brakes on the bike were originally just Shimano Deore LX cantilevers, but at some point the owner got fed up with the lack of stopping power on the back (caused by the off-center cable stop), and upgraded to more powerful Deore XT V-brakes. We took things a step further by installing the most complicated looking V-brake ever produced for the front position, a nice compliment to the suspension fork machining, no?
The bike in general is a pretty simple design considering all of the complicated-looking details. Consider riding over a bump: As the rear wheel moved upwards, the seatstays push into the rear shock directly. There is no linkage that would change the direction of this motion. The shock units used on other bikes would probably have fallen apart from the stress, but AMP’s shock unit featured a damping system that could handle lateral stresses normally absorbed by rigid frame pieces.
The AMP model B3 was a slightly more durable and refined bike than the preceding AMP B2 (which was their first production bike).
Dan Priest 1995 NORBA Nationals
1995 Police & Fire Games
Greenlake Cycles Team w/ Dan Priest
Amp front end
XT derailleurs, Specialized crank
Technology-wise, this bike was at the cutting edge. A 24 pound full-suspension bike (that actually worked pretty well) in the mid ‘90’s. A Scott AT-2 handlebar with the bar-end extensions built in. ControlTech aluminum seatpost and handlebar stem. An ultra-light Specialized crankset with a titanium bottom bracket. Clipless mountain bike pedals (the original pedals were Shimanos, we have Time pedals in the photos now). Great stopping with V-brakes and ceramic-coated rims.
So a little bit about the rider: This bike belonged to a Kitsap resident named Dan Priest. He did most of his own bike work, so we didn’t know him well, but we knew a lot of his cycling friends. Dan was an avid bike rider for most of his life. We have a late ‘70’s Raleigh Competition road bike of Dan’s that traveled thousands of miles by the look of it. If you click on a couple of the pictures here you’ll see a team photo with the Gregg’s Greenlake road racing team from sometime in the early ‘80’s (judging by the hair). In ‘95 there’s a shot of Dan and the Amp B3 negotiating the NORBA national cross-country course and another from the ‘95 Police & Fire games.