thegoodfellas/blogset-br huggingface dataset:
elevated short-travel setting, the Jekyll 4 climbs steeps with an ease that defies its 31-pound weight figure. The steering feels a tad steep, but that doesnt seem to hinder its technical ability. During the downhill phase of testing, one of our test riders was happily launching road gaps. In short, the Jekyll 4 got the all-mountain stamp of approval well before the testing was done. Stylin' it off the boulders - Ken chills on the Jekyll with another 35 feet to go to make the transition. Ian Hylands photoSet-up notes: The Dyad pull shock cant be read for sag unless you have a friend around to measure it (the shaft retracts at rest, so an O-ring indicator wont work). Otherwise, it was the easiest bike to get right. Follow Cannondales printed negative and positive pressure recommendations printed on the seat tube sticker (or visit Foxs informative Dyad tech page). Up front your options are slim - verify your fork sag (printed on the Sektors stanchion tubes), set the rebound and you are good to go. The Sektors coil spring must be preloaded internally with spacers if the sag is more than recommended (spacers included by Cannondale).Pedaling/Acceleration: Even with the unlikely Hans Dampf knobbys, Jekyll riders could easily spin the big ring on fast, smooth dirt and pavement thanks in part to the shocks short-travel mode and the forks lockout setting. Still, it is a relatively heavy bike and that can be felt anytime one is forced to brake and re-accelerate strongly. With all the aids switched on (shock and fork shortened), the Cannondale can be pushed hard up and over rollers and out of flat corners, but it lags a bit with the first few pedal strokes when accelerating from a dead stop. In its favor, the Jekylls frame is famously stiff feeling in torsion, which can be quite a morale booster when trying to reel in an opponent, because you can be certain that you are not wasting leg power on mushy suspension and a flexible frame.Climbing: On the dirt, with its suspension set hard, the Jekyll 4 makes good time uphill. When the trail got exceedingly steep, lowering the fork was a welcome help to keep the front tire planted on the ground. That noted, it doesnt feel overly energetic, it just makes its way upwards effectively and without a fuss. While this feel is typical of almost all bikes in its class, the Jekylls overall climbing speed is at least a gear faster on smooth surfaces.With its grippy Hans Dampf, knobbies and slightly steeper steering geometry, the Jekyll negotiates tricky climbs with surprising dexterity. Add its thankfully low, 22-tooth chainring and its rider can maintain long pitches of murderous steps and ruts without triggering a pulmonary event. I often clicked the shock into short-travel mode, because it raises the rear end about a degree and gives the bike better balance especially when climbing touchy switchbacks or slickrock. The Jekyll 4 and its aggressive Hans Dampf tires managed to find traction almost everywhere on the gravelly, hard-pack soil - and
when it did let loose, it drifted smoothly. Ian Hylands photoTechnical handling: Cannondales choice of a coil-sprung Sektor fork was a deal breaker for heavier riders who complained of brake dive while negotiating steeps and drops. Riders under 169 pounds, however, reported that the Jekyll felt secure in similar situations. Cannondale packs plastic fork spring spacers to preload the fork and help solve this problem and if that doesnt work (it did for us), RockShox offers three spring options for riders who are lighter or heavier than the national average. With its 67.8 degree head angle, a competent rider can take the Jekyll down some tricky descents and during the downhill phase of the test, riders raved about the bikes cornering and tire selection on the dry, unpredictable surfaces. Still, with the soft fork, a little brake dive can turn that 68 degree head angle into 70 - and we all had one Hail Marymoment.Downhill: Initially, I felt less confident dropping down untried sections aboard the Cannondale, but after four rides, I learned that the Jekyll was much more trustworthy than first apparent. Once I got off the brakes and let the Jekyll go, I discovered that it was quite smooth through the corners and stable when I got the wheels off the ground. Armed with the grippy Schwalbe tires, I could drop the wheels into substantial ruts and it would pop right out, which inspired confidence while scouting unfamiliar routes. Experienced downhillers in the test did not have trouble acclimating to the Jekyll and spoke highly of its cornering and ability to change direction. I learned to put a foot out when I really pushed the bike around flat corners because when it let go, the Jekyll was quite a drifter (a trait that at least one rider raved about). While on the subject; the Jekylls Avid Elixir 3 brakes were a sore point, with a squealer up front and pads with an indistinct feel that once locked up, required almost a complete release at the lever to unstick the tire not an optimum condition for steep sketchy chutes. It should be noted here that the sticky brakes may have been caused by an improper bleed. Suspension trials at Teds. Trail builders constructed oversize chatter sections on the course specifically to test fork and shock tunes. The Jekyll's Dyad-powered rear suspension surprised us with a relatively smooth ride on the higher speed bumps. Underline 'relatively.' Ian Hylands photoSuspension action: Surprisingly, the Cannondale suspension was a top performer, We didnt have much initial faith in the Dyad RT2 shock, but it delivered in the rough, taking the biggest hits without a fuss. Not saying that the Jekyll is as plush as a big bike it absolutely isnt but it can take a lot of punishment and hold a line. With a fork upgrade, the bike could be pushed much harder still. In short travel mode, the feel of the Jekyll is that of a short-stroke XC rear end. It pedals easily and takes the dullness out of the drivetrain. The Sektor fork
took a lot of oomph to set into the short-travel mode. The fork must be compressed 75-percent of its stroke to set the travel, and that is not easy while climbing technical ascents. Because of this, we often gave up and slogged up steeps with a sketchy steering fully extended front end not a big worry, but still, having the option and not being able to get it is a pain. Opened up, the RockShox fork was pretty plush feeling and relatively sensitive while cornering at speed over rough surfaces. Good stuff from a value-priced fork. Component report: Small details, but important ones, appeared on the top and bottom of our love list. Aluminum endcaps on the lock-on grips were sweet, the bars were never plugged with dirt, so neither was the car, the living room or the shop where dirt harvested by other handlebars usually ends up. The fit of the frame and seatpost was smooth, the action of the well-made quick release seatpost clamp was butter smooth and the full length of the post could slide into the seat tube for DH runs. All was not wonderful, however. We like Syntaces quick release through axles, but the Jekylls Syntace X12 rear axle was a hassle to operate. The axle required a shove to get the threads started which was nearly impossible to do with one hand, because the Allen wrench required to tighten it slipped into the hollow axle. By contrast, the RockShox Maxle Lite up front was always a breeze to operate. One upgrade that wed love to have is a double crankset (22 x 38 or 36) with a bash ring in place of the third sprocket. We rarely used the big ring on the dirt and always bashed it on something. Finally, wide handlebars please? The consensus was, at least 720 millimeter width bars for the Jekyll. Pinkbike's Take: Somehow, Cannondale turned its ordinary single-pivot suspension design into a star performer. For $3000, the Jekyll is a sweet deal for a capable bikehandler that wants a do-it-all trailbike. It is no surprise that the elite level Jekylls are ripping it up on the Enduro circuit - and the Jekyll 4 shares the same frame numbers and suspension. Out of the box, Cannondale put together a true all-mountain bike for an affordable price. Add a more capable fork and some hard-stopping brakes and the Jekyll 4 would be tough to beat at any level - which is the unspoken sell of the Jekyll 4. At its core, the frame and suspension is a truly elite level chassis, so investing in expensive upgrades like a more capable fork and a dropper seat post would be money well spent. - RC
EXCLUSIVE: DVO Emerald Inverted DH Fork - First Look Nov 13, 2012 Add to my Favorites It has been a quick seven months since DVO, short for Developed Suspension, was formed after Bryson Martin and engineer Josh Baltaxe departed from Marzocchi. Bryson, who has been in the suspension game for 23 years, quickly began outlining a plan to offer something different than what consumers may be used to, not just from a product standpoint, but from a company approach that contrasts with what many have come to expect. ''I really wanted to do it right, so we needed everything all under one roof and thats what we have accomplished,'' declares Martin. ''Now that all the ideas, designing, and engineering all happen in one place, its a lot easier to set goals and execute on them.'' It wasn't long before both Tom Rogers (product development) and Ronnie Dilan (head technician) left Marzocchi to join Martin and Baltaxe and plans were laid for DVO's debut fork. Whereas the current major suspension players all offer a massive range of products to choose from, DVO plans on producing a limited selection of high-end products, beginning with the 203mm travel, inverted Emerald shown here on Pinkbike for the first time.We know the benefits to an upside down fork and it's been a very long time since a company brought an inverted fork to market. We wanted to make a statement by executing it when other companies couldn't.- Bryson Martin, DVOWhile this is the very first complete Emerald to be assembled, each of the fork's different elements have been tested in some way during development. The Emerald's open bath twin tube damper system, for example, was surely put through real world testing while hidden within another fork maker's chassis, likely making its way down trails and past other riders without anyone taking notice. Martin is understandably coy about what fork the damper was trialled in, but he did reveal that early versions of the Emerald were coil sprung prior to the air spring system being developed. The fork shown here, as well the production model, will make use of an air spring, and DVO is also looking at including an adjustable volume feature that will allow riders to tailor the fork's ramp-up through its stroke. Interestingly, it will employ a coil negative spring that will have an adjustable preload component to let Emerald owners adjust the fork's initial stroke. Emerald Details Intended use: DH/FR Design: Inverted Travel: 203mm/8''Stanchions: 36mm w/ molybdenum disulphide coatingUpper tubes: 43 - 41mm tapered 7000 series aluminum Steerer tube: 1 1/8th straight or tapered options CTA: One-piece Carbon Torsion Arch acts as stanchion guard/fender while increasing torsional rigidity by a claimed 50%Fork crowns: Forged and CNC machined. Separate crowns for 26'' and 650B-sized wheels to preserve trail geometry, direct mount stem compatibleSpring: Air Damper: Twin-tube open bath design External damper adjustments: Separate low and high-speed compression/rebound Negative spring: Coil w/ adjustable preload Target weight: 2,900 - 3,000 grams/6.4 - 6.6lb Availability: June/July of 2013 MSRP: To be announced Inverted DesignThe DVO team knew they
wanted to pursue an inverted layout for the Emerald due to the design's lighter un-sprung weight, consistent lubrication qualities, and ease of compatibility with non-26'' wheel sizes. And while those points are certainly all valid, there is a reason the large majority of suspension forks on the market employ a traditional right-side-up layout: torsional rigidity, or rather the inherent lack of it in an inverted design. Inverted forks are ubiquitous in the motorized off-road world, as proponents of the design are quick to point out, although it could just as easily be argued that weight is much less of a concern on a dirt bike, therefore allowing for massive tube diameters, thicker tube walls, and burly crown and axle clamps, all features that make for a much stiffer (and heavier) fork. But even when similar methods are applied to the front end of a mountain bike, the result can't approach the outright stiffer design of a right-side-up fork. Is that necessarily a bad thing, though? ''Compliance on a mountain bike can be a great advantage but it must be in the right locations,'' says DVO's Bryson Martin. ''As more DH and Enduro frames are made from carbon where stiffness is generally accepted, the suspension must become more compliant - structurally and hydraulically - to optimize the entire bike.'' We feel that the industry puts too much emphasis on stiffness in general. Stiffer doesn't always mean better.- Bryson Martin, DVOThe general consensus for most mountain bikers, though, is that one's front-end can never be too torsionally rigid - it is a mantra that has been drilled home thanks in large part to manufacturers claiming massive gains in stiffness with every new product. But is stiffer actually better? There is certainly a point where too much torsional flex will begin to have a very negative effect on performance, making for vague and unsettling handling but, as Martin alludes to, just the right amount of torsional compliance can also allow the front wheel to track more smoothly on rough ground, something that designers at the top flight of MotoGP, among other sports, have known about for many years. It is a little known fact that, during testing, one downhillings most successful racers actually cut the arch off of his right-side-up fork in a search for more torsional compliance! So, if a given amount of torsional compliance can be an advantage, the question remains: how to tune-in the desired amount without creating an overweight fork? DVO's answer lies in their proprietary Carbon Torsion Arch, or CTA for short.Carbon Torsion ArchLikely the biggest talking point of the Emerald will no doubt be the carbon fiber, bolt-on CTA unit that serves to not only protect the stanchions from damage and as a fender, but also to tie the lower legs together to increase torsional rigidity by a claimed 50% over the same Emerald fork without the CTA in place. The basic idea isn't new - riders who have been in the sport since the mid-90s will likely recall the inverted, elastomer-sprung and air-damped Halson fork that had its
lowers joined together via a brace that traveled vertically by way of slots machined into the fork's uppers. The CTA's execution looks to be much more impressive, but we'll need some trail-time on the Emerald to see just how effective it actually is.The unit features a unique core (Martin was reluctant to share certain details at this point in time) within its otherwise full carbon fiber construction, with the design said to resist torsional loads while still being light, strong, and durable. DVO isn't simply trying to add as much rigidity as possible by incorporating the CTA unit, though, with Martin stating that ''This design will still offer some pliability, especially useful in rough, straight line sections, while providing stiffness in corners.'' A number of different CTA elements are in testing that use varying carbon layups with an eye toward a final design that offers the rigidity and balance DVO is looking for. The idea for the bolt-on carbon element came about well into the fork's development; DVO was investigating how axle size and shape factored in long before the Carbon Torsion Arch was added to the Emerald's spec sheet. Interestingly, the idea of a hex-shaped axle (much liked those utilized on Manitou forks) was nixed when DVO found that increasing the overall clamping surface area of the axle proved to be a more efficient way to control slipping and flex. No, you won't find some oddball-sized axle utilized on the Emerald, but rather a very stout looking 20mm setup.Being competitive in weight is definitely high on the list, but performance, reliability, and strength was more important for us, especially for the kind of abuse a suspension fork endures. 2,900 - 3000 grams is our target and we hope we are close but, more importantly, we want people to be stoked on the performance, adjustability, and durability of the fork.- Bryson Martin, DVOThere is no denying that the Carbon Torsion Arch concept is a clever way to go about increasing torsional rigidity without adding too much weight - DVO claims that it should only add about 200 grams to the package - but the question remains as to why such a design hasn't yet been put to use in the motocross or enduro realms. If the CTA unit is as effective as DVO asserts we may see it pop up in other places as well, including an inverted single crown fork further down the road, although that could be a ways out at this point. We always want to look at each project individually and design a product that is optimized for its specific use.'' Martin continues, ''It follows our plan to stay focused and not just throw gizmos and features into a product that ultimately drives up cost and over complicates things for the end user.'' The Emerald uses a traditional 20mm thru-axle that requires tools to remove. You won't find any funky quick release axles or strange locking methods here.Twin Tube DamperThe two most common damper layouts currently being employed within forks are either a sealed cartridge layout (FOX with
their FIT cartridges, and RockShox, who turn the stanchion tube into the cartridge body) or an open bath cartridge (ala Marzocchi), with advantages and disadvantages to both designs when it comes to performance and weight. The Emerald doesn't make use of either one, though, instead employing an open bath twin tube layout that DVO feels is much better suited to long travel applications. ''A pure open bath system can have issues with aeration and cavitation, as well as having too much oil that adds unnecessary weight,'' Martin says. ''Twin tubes solve those issues, keeping damping consistent and oil volume to a minimum.'' And while damper design is a topic that often results in endless arguments as to what actually does function best, the twin tube system is is found within some of the most acclaimed off-road moto suspension designs, especially those created by a certain highly rated Swedish company. A moto-inspired philosophy is one that rings true through much of DVO's thinking. The fork's base valve and rebound assembly, complete with mid-valve (left). Tom Rogers shows off the fully assembled twin tube damper body (right).While DVO is adamant that the open design of their twin tube damper makes the most sense for a pure DH fork, we might see something entirely different utilized within any shorter travel forks they may or may not produce down the road. According to Bryson, There is more of an advantage to running a closed system on a fork with less than 160mm of travel compared to using the same system on a fork with 203mm of travel.." This train of thought is in contrast to some other suspension companies who employ the same basic damper philosophy throughout their high-end fork lineup, be it a cross-country or longer stroke downhill offering.When it comes to damping, it isn't about reinventing what has been proven in other areas, but about delivering value and performance to the end user, without the gizmos and hard to service designs.- Bryson Martin, DVOThe twin tube, open bath damper is exactly as its name would have you believe, with a secondary tube that sits within the fork. The damper piston travels up and down within this tube, but as opposed to it being sealed, oil ports on the wall of the tube allow damping oil to circulate between the inner and outer tubes, and through the valving. This layout should result in less cavitation (the formation of bubbles and foaming of oil under hard use), making for more consistent damping, and an optimized oil level that also acts as lubrication to keep the fork cycling smoothy through its stroke. Enclosed in the damper body is DVO's 'Emerald Valve', otherwise known as the piston. DVO has gone to great lengths to create a piston that permits a lot of oil flow via smooth, open porting. This lets them control the fork's damping characteristics with more shims than would otherwise be required of a lower-flow piston, the advantage of this being a large degree of tuning by way of using more and different shims. The fork
also uses shimmed rebound damping as opposed to a ported system, which is what some other suspension companies employ. Ported damping refers to oil flow through small holes, known as ports. One potential issue with ported damping is that at times oil simply cannot flow fast enough through the ports when required, resulting in very inconsistent damping. Shimmed rebound, on the other hand, allows for the same dynamic damping (the shims flex more or less depending on the forces involved) as found on the high-speed compression side of the piston. The Emerald's adjustment dials are sturdy aluminum units that are clearly labeled. Separate low and high-speed rebound is adjusted atop the right leg, while separate low and high-speed compression can be tuned via two dials at the opposite end.User Tuneable DamperThe moto-inspired approach continues with DVO's decision to not only allow Emerald owners access to the entire damper assembly, but actually encouraging them to try their hand at tuning it. This is the exact opposite strategy that most suspension companies within the mountain bike world have taken throughout the sport's history (Manitou is an exception, though, with their Absolute Plus Tuning kit), with many riders being downright scared of opening up their fork or shock as a result. Yes, a certain amount of knowledge and skill are required, not to mention the correct tools for the job, but it is far from being rocket science. DVO will offer not only tuning kits, complete with shim layout suggestions and the expected results, but also on-line videos that will guide owners through the process. Taking it a step further, they also plan to hold in-house tech seminars for those who really want to jump into the deep end of tuning.Since we rely heavily on piston and shim stacks to handle our damping, we have designed our pistons to be easily accessed so individual shim stack tuning can happen. Once the rider becomes comfortable with working on the suspension, it is very interesting to test different settings tailored to specific riding areas and skill level. We are committed to teaching riders all about suspension and we will provide a lot of information on how to tune our products so you can become your own suspension tuning guru!- Bryson Martin, DVOFurther helping matters is the Emerald's 'bottom loader' base valve that should allow owners to make changes to the damper without having to perform a full rebuild. Simply flip the fork (or bike) upside down, unscrew the compression base valve from the bottom of the fork leg, and pull it out. Minimal, if any, oil loss should occur. All dials are contained on the assembly, meaning that you won't have to fiddle with near-microscopic set screws or any tiny indexing ball bearings or springs. We've long said that most mountain bike suspension companies seem to go out of their way to make damper service and tuning a huge hassle, and it is a breath of fresh air to hear DVO's approach - garage tinkerers rejoice.Titanium Collet ClampsAll current double crown forks in the MTB and the