Strengths: Climbs like a mountain goat, very tough, good stable suspension system. Very easily & afordably upgraded. AMAZING 26" bike.
Weaknesses: Hard to retrofit w/ disk brakes.
This is overall an AMAZING bike, I got mine off web years ago, & have upgraded overtime. The geometry of the bike provides great downhill and uphill capacity. There are lots of upgrades (Nulife cycles) that add to the bike for a great price. My pro flex is capable of keeping up w/ just about any rockhopper out there (after upgrades of course). They don't come w/ disk brakes, but stop very well. Very strong bike, able to take savage punishment, good clearance for an old style bike. In my opinion this bike was ahead of it's time!
from Meaford, Ontario, Canada
Date Reviewed: April 29, 2010
Strengths: This bike handles amazing, the front suspention absorbes ever shock and bump from my jumps, gaps, and drops. It tackles sharp corners with no problems. This bike can pretty much handle anything i throw at it.
Weaknesses: I found thw brakes to be a little weak, but that is due to the age of this bike, the tires are too thin for a solid mountain bike, on top of that, the tread didn't provide the proper traction i needed.
I came to this site looking for some info on this bike i have, my mountain biking team just started back up and after reading said reviews, this is going to be my racing bike for the season. I have since replaced the brake shoes, and upgraded the tires to 3' self sealing Maxxis tires, which provide amazing traction. I really wish this bike had come with optional disc brakes.
Bike Setup: Origional frame and paint, origional suspension, new gel seat, new brake shoes, uprgaded forged aluminum pedals and cranks, Maxxis tires on custom pained rims stripped of an old Specialized Hardrock to match the bike frame color.
Date Reviewed: June 6, 2008
Strengths: THe Noleen shocks sucked up everyting in sight. The Girvin was stiff and tracked like a rigid fork. The Girvin fork has zero flex allowing it to be driven hard into corners. This was a great climber for a full suspension. The pivot location pulled the rear tire into the ground resulting in great traction. I was able to climb areas others could not.
Weaknesses: Weight. The bike was a little heavy. The stock Wild Grippers were terrible. I might have been better off riding on the rims, these tires offered little traction. The small frame set up does not have room for a resovoir for the rear shock.
This bike was awsome. I would still be riding it but it was stolen in FL. It climbed, it descended, it was a great all around bike. I raced it and did very well. There was little I couldn't climb or go all out through with confidance. This included tight twisty and wide open flat out courses. It is a shame K2 ruined the bike through design changes, poor marketing and everything else they could do wrong.
Bike Setup: Full XTR with Magura hydrolics. Would have put disks on it but a feasible set up was not available.
a Cross Country Rider
from Toronto, ON Canada
Date Reviewed: August 6, 2006
Strengths: When I bought this ride in 1995, it was the plushest product on the market (important for me because I have pins in my right hand) and was looking for something that I could ride for 8 hours at a time. The MCUs did the trick (until they dried up).
Weaknesses: MCUs had a limited life.
I have had this ride for 12 years now, and have toyed with the idea of getting a new ride for the last 2 years. Each time I've tested new rides, I've been shocked back to life with the question; "Why?" This bike has absolutely nothing wrong with it. It still looks great (I get comments from young riders who have no idea how old the bike is, and also from older riders who actually remember the brand quite favourably and are awe-struck that this ride is still going), with all-original, unflecked paint!!! Outside of updating the front and rear suspension with Noleen NR2s (once the MCUs died), I've done little to change this ride. I did end up changing the stem and bars for a more comfortable reach (Icon and Easton respectively), and then changed the original saddle for a Bontrager Gel. Everything else is original. And this ride has been out to B.C. to ride the North Shore, Squamish and Whistler about 8 years in a row; down to Vermont eight years in a row and also to Moab, Utah. I ride almost every week somewhere in Ontario during riding season (April to October) and by no means baby it. For it to still look brand new is a great testament to Bob Girvin and his incredible product.
Favorite Trail: Three Stages, Collingwood, Ontario
Duration Product Used: More than 3 years
Purchased At: 1995 Toronto Bike Show - Silent Sports
Similar Products Used: Prior to this ride I had a Kona Hardrock and a Stumpjumper.
Bike Setup: 1995 855 with Magura Raceline hydraulics; GripShifts 6.0; Easton EA50 MonkeyBar risers; Icon stem; Noleen ELT CrossLink front fork; Noleen NR2 rear shock on GLS swingarm; original NukeProof hubs and Mavic rims; Shimano XT front and rear derailleurs; Bontrager Gel saddle; Sugino CSSII crankset; Shimano 747 pedals
a Cross Country Rider
Date Reviewed: July 12, 2006
Strengths: Great climber for a FS bike Tracks beautifully Stable platform
Weaknesses: Suspension Travel is limited by today's ('06) standards
I bought this bike as a leftover in '98. I have put over 2,500 off road miles on it. I wore out almost every part on this thing except the BB (go figure). I'm not small so I don't blame the original parts at all.
I retired it in 2002 for the Giant but rode it occasionly just for the joy of it.
I have since been using it as my lunchtime ride and it brought back many fond memories of my earlier riding days such that I thought I would do it justice by writting this review.
Similar Products Used: Proflex Attack ('96), Giant AC Air Lite, Cannondale Hardtails
Bike Setup: XT/LX, Hellbent bar, Terry Fly Ti saddle, Shimano 747 pedals (why did they stop making these??), Panaracer FireX tires, Mavic 222 wheelset, Thomson Seatpost & Stem, TrueVativ cranks
a Cross Country Rider
from Halifax, Nova Scotia, Canada
Date Reviewed: July 6, 2006
Strengths: Excellent frame and geometry. Rides like a buck taking off from the hunters during the season. Versatile bike, good for grocery getting and hardcore riding...this bike rocks!!! She's a performer!
Weaknesses: Old shocks sucked...Noleen sucks!!! I have since upgraded the front shock to a Rock Shox Judy XL, and the rear shock to a Reese Racing shock...SWEET, with no creaks or noise, perfect rebound and damping.
This bike ROCKS on the trails, and rides like a scared buck during hunting season!!! Soaks up the bumps, and climbs like a Billy Goat! After upgrading the suspention, all creaks and noises were eliminated, and this bike kicks BUTT!!! I've ridden the TOP end bike sold by Serotta, Specialized, GT, and Cannondale since buying this thing, and they all suck in comparison! (I-Drive comes close, but no cigar, and now GT sold out to Walmart...lol). This is the perfect full suspension mountain bike, and I will keep her for life. Reese shock is great, air adjustable, and has continually sustained my 250 lb arse.
Favorite Trail: Prince Edward Island coastal trail
Duration Product Used: More than 3 years
Purchased At: Ebay auction
Similar Products Used: Litespeed Tsali, Litespeed Unicoi, GT I-Drive, Fat City Monster Fat, Fat City Yo Eddy.
Bike Setup: XT drivetrain, Reese rear shock, front Judy shock upgraded with a Wings gas kit.
a Cross Country Rider
from Virginia Beach, VA, USA
Date Reviewed: June 28, 2003
Strengths: Beautiful welds, not "squeezed from a toothpaste tube" like some aluminum frames. Light and stiff. Replacable derailleur hanger. Bought as a frame only, but once built, exceeded my expectations dramatically!!!
Weaknesses: Paint chips easily. Bearingless pivots squeak unless greased often (proper maintainance, so I'm nit-picking). Rear V-Brake noodle rubs left heel unless you loosely zip-tie the brake and shifter housings together right behind the bottom bracket.
This bike exceeded my every expectation!!! It is light, there is very little bottom bracket flex, and it handles like a high-end hardtail. At first I thought the long (17") chainstays would slow this bike down. NOT!!! She handles the technical singletrack like a dream. She climbs like a mountain goat on steroids, and decends like a dream!!! This ended up being the perfect light weight cross country machine for me. I'm a clydesdale finesse rider, and she suits my riding style perfectly. I detected no pedal induced bobbing, and the bike just disappears benieth me like she is supposed to do. She rides like a hardtail, but soaks up the bumps all day long. Seated with the proper shock sag, the headtube/seattube angles are a perfect 71/73...SWEET!!! With the light weight and only 3" on travel, I cannot recommend this bike to the down-hiller or "freerider". But if you are looking for the sweetest XC rig out there, and can find one of these frames used, BUY IT!!!
Similar Products Used: Univega Alpina Trail, Nishiki Saga, GT Tequesta, GT I-Drive, Litespeed Tsali, Cannondale Raven, Fat Chance Yo Eddy, Specialized S-Works... and a myriad of other friend's bikes over the many years I've been riding and racing (since the mid 80s).
Bike Setup: Total weight when I built up the frame is 25.2lbs. SWEET!!! Since I bought it as a frame-only, I didn't uses the Noleen shocks, so I can't comment on them. Risse Racing in the back with 250psi to accommidate my 230lb clydesdale self. Judy XC up front with a Wings tuning kit for the same reason. Profile Carbon flat bar, Trek OCLV bar ends, SRAM X-Ray 8-speed shifters, Tech-lite brake levers, Lizardskins grips, Salsa stem, WTB Momentum headset, American Classic Seatpost, Flite kevlar saddle, XT hubs, WTB rims 32f/36r, Michelin Wildgripper Lite S tires, XTR 12-32 cassette, IG chain, XT front derailleur, old DX short cage in the back, XT V-brakes, Ride-On gore-tex cables, Minoura bottle cage, with the bottle cage mount behind the seat used for mini pump and Topeak 21 tool. Speedplay Frogs are my pedals of choice.
a Cross Country Rider
from San Francisco
Date Reviewed: November 28, 2001
Strengths: Great bike to ride, excellent comfort. I do not have the Noleen fork. I purchased a '99 Marzocchi Z1 fork for this bike. The rear swingarm is built well and you can literally feel the rear wheel diggin into the trail as you climb uphill. It is a very good design for it's time, but I think there are more promising designs today. I still stand by the 857 as it's one of the best series to buy from Pro-flex. Stiff carbon fiber rear swingarm.
Weaknesses: You'll need to make a bit more slack for the cable housing and cable. My deraileur will auto shift sometimes when I compress the rear suspension too much because I didnt use enough cabling to compensate for this. The Z1 fork compresses a bit much for XC riding but can clean many of my routes 2 times faster on this rig than my Procaliber can.
Get the bike if you don't want to huck away all that precious dough on something you'd rather look at than throw mud at. Its a very fun bike and handles exceptionally well through singletrack and bunny hopping trails. I have confidence in the rear-carbon swing arm since it is stiff and I do have some sense on how to land a bike properly (listen up kids that break bottom brackets left and right). It's a bit flashy, so you better be up to prove what your made of.
Similar Products Used: Proflex Beast (heavier). Schwinn Homegrown Full suspension
Bike Setup: Billet Precision stuff, Powerflex shifters. XTR this and that, all worth it in the end =)
from Lancaster, Ca USA
Date Reviewed: October 25, 2000
Strengths: Plush, very adjustable, the cable stops are set up to take massive cables (like hydraulic lines for Magura brakes), climbs like a hardtail and descends down like a downhill.
Weaknesses: Weight is a little much. The gearing on the cranks are a little too small for me, but that's just preference and I doubt that was originally on the bike.
This is the best bike that I have ever ridden. I went from a Mongoose IBOC hardtail to this full suspension. I was expecting to be sacrificing my climbing ability. I was wrong. This bike handles and climbs just like my IBOC, but it is plusher on the downhills. Plus, it has nicer parts than my IBOC. I would recommend this bike to anyone who can still find one. If you see this bike in a bike shop for sale, buy it immediately!!! The only bike that I have found that can compare with this one is an Amp B4 and they are hard to get, hard to find, and when you do it'll cost you around $3,000. I wish that I could give it a higher rating than 5 chili's, because that is what it earns.
Similar Products Used: gary fishers,cannondales,giants
Bike Setup: nolleen smart shocks f/r
a Weekend Warrior
from Cuyahoga Falls
Date Reviewed: November 18, 1999
Strengths: Handles great. light weight. looks cool. great for moderate DH. excells at mixed terrain XC. doesn't mind going up. full xt component group is great.
Weaknesses: rebound adjuster broke on rear shock assembly.
I love this bike. I rode a friends 857 and I was convinced within 5 minutes that it was 'the bike' for me. I'm going to upgrade the brakes to Magura HS-33 hydrolics and upgrade the drivetrain to Shimano XTR or some sort of custom drivetrain. I am not 100% satisfied with the performance of Shimano's XT drivetrain. Since the drivetrain problem belongs to Shimano and not ProFlex/K2, I must give the 857 5 of the biggest flaming chili's you've ever seen.
Similar Products Used: LTS team,Ventana, Specialized FSR
a Cross-Country Rider
from Las Vegas, NV
Date Reviewed: October 12, 1999
Strengths: Great F/S frame, works well climbing and descending, lightweight, Crosslink rocks!
Weaknesses: We'll see as time goes on....
I have rode ProFlex (855/856) for the last 4 years, and always liked the lightweight setup and handling, but the suspension was pretty poor with the elastomers. I got my 855 frame warrantied for weld cracks, and got a new 857 frame out of the deal. With all of the closeouts available on this frame, GET ON THE BANDWAGON! With the Noleens, this bike just comes alive! It is both a great climber and descender. I have built it up as a lightweight X/C rig. If you rode an 855 or 856 and were unhappy, this bike solves everything! I hope my Noleens hold up and that I don't have to go to K2 for anything, as they don't have a shop in Vegas. I think K2 is having some problems with their MTB line in general, and I hope they can save it because this bike is sweet!
Similar Products Used: Proflex 855 & 856, Cannondale Super V
Bike Setup: 857 with carbon fiber Crosslink, NR-2s front and rear, Dave's wheels, SRAM shifters, Raceface cranks, XTR brakes
a Cross-Country Rider
Date Reviewed: July 17, 1999
Strengths: Climbs well Absorbes the bumps Decent all-round bike
Weaknesses: Rear NR2 Shock
I do like this bike.I purchased the 857 frame 6 months ago for £399, and built it to my own specification. I was very impressed with the way the bike handled. I ride to college(road), singletrack, X country, and a bit of downhill.The bike coped with whatever obstacles i could throw at it.The only major problem i foresee, is the rear shock. I was riding my bike down a dirt track, which was not particularly bumpy, and the rear shock snapped in half! I was gutted! (not a good day, hours before i split up with my girlfriend, but that a different story!)I sent the shock back to the place of purchase along with a bent strut.The shock returned about 10 days latter, but i am still waiting for a new strut. After reading other peoples reviews of this bike, i can perceive that the NR2 shock will cause me a lot of grief (i am considering changing it for a Risse rear shock instead),because of this unfortunate fault,i can only award this otherwise excellent bike, 4 stars.