Review: DSP Dueler FR 7.875 x 2.25

Once again the good folks from DSP dropped off a package last week. This time around its one of the new, smaller boinks aka Dueler FR shocks. Prior to this the smallest available was the 8.5 x 2.5"

These new available ones comes in:
7.5 × 2.0  (E to E 190mm, Travel 51mm) 
7.875 × 2.0  (E to E 200mm, Travel 51mm) 
7.875 × 2.25  (E to E 200mm, Travel 57mm)
 with either a 400 or 500lb Kronos Ti Coil.

Being popular sizes on many  frames in the market, this would surely open up the option for those who may want to find something a little different from the few usual brands.

Externals
Spotting the same quality finishing as their bigger cousins, there is the lasting hard coat anodizing. Something my oldest Dueler can bear witness to after 2+ years of abuse with just minor fading. Usual attention to details for their shock are pretty much the same. What's done right all along are applied to these new shocks as well. The long of it, has already been covered in my earlier review of the 8.5" x 2.5"

Of course, just looking at the new graphics on this one would you make you 0.5 seconds faster.
In addition all the Kronos Ti coils now receives an anti-UV lacquered surface. While I'm not really a big fan of glossy things.. but the easy cleaning and keeping the spring stain-free  is something that can be appreciated.

It is comparatively light when pitted to other similar sized coil shocks out there. Running an air shock with piggy will probably set you back by 430-480gm. For the 7.875" x 2.25" here with a 400lb coil at 642gm, this would be less than ~150-200gm difference (that's less than 1/2 lb for all ya metric-challenged readers).

If you are looking for that coil performance with the "lively" ti spring feel, just  stop right here and  just go look for the nearest distributor. Pricewise, its not about being competitive. They just sweep the table up from the competition if its only based on this one factor at ~60-70% for what you have to shell out with other big brands...

More importantly is whether it works.. So far from using the bigger ones, it I'll just summarize it as  "Simple shock mechanisms with easy operation of adjustments that has actual usable range and pretty much fuss free" (at least for me).

It would seem like a repeat of what has been reviewed previously. However the time it has taken for these smaller shocks to be tested  and made available only recently says something else. The internals probably received some tweaks as innards like shimming and seals etc would obviously have to be fitted into a smaller volume of shock body and the respective sizing of the internal bits have been reduced?

Wouldn't be to hard to think how changes are needed to overcome some of the constraints and the mechanics as space within shock body, x-sectional areas diminishes.

It is easier to make a bigger shock work well but as size diminishes, it gets harder to cram and tune everything within yet still suit a broad range of riders with varying weights.

Size comparison between the 7.875" (top) and a 8.5" (bottom)

Compression knobs are the familiar, non-indented ones. ~2.333 turns of adjustment on both the hi and lo comp.

The only noticeable difference vs the bigger Duelers is the rebound range. Apart from being stamped  with the letters "FR", it is 1 full revolution less (max 2 turns on my piece) compared to 3 on the bigger size shocks. Spec data indicates info for force/loads up to 1.5 turns of the rebound.  Maybe something to counter/offset with the workings of others internals within?

Left: Dueler FR 7.875 x 2.5" Right: Dueler 8.5" x 2.5

Quite frankly those numbers are like reading off a weather chart for me. All I can gather is that this shock probably runs a different rebound needle..as to whether things work-- well that's what the real life test riding is for eh!

 
The Ride
'Nuff with the maybes and e.theorizing... time to break out the my nerve-ending enriched butt for some test and calibration of the shock.

Nothing big and adventurous as its just the first ride to set things up for a long term review.. 

As luck would have it the sky decided to pour half the Pacific over our head just before the start. Well , that just puts things back in my favorite element--  Wet-"n"-Wild roller coaster ride. Nothing better to test traction...

The setup
Riding weight 170lb
The Dueler tag-team with a Vengeance Coil 170mm up front on a small De Vinci Dixon running the Spivot design.  2.5 Minion DhF upfront and a death grip 2.35 Hans Dampf pulling rear duty completes the essential things that would interact and relate to the shock's performance.

Initial Shock Setting
Lo comp --fully open
High Comp -- 3/4 turn from minimum
Rebound -- half a turn from minimum

Comparative feel with other shocks
A quick word... some bikes are optimized to run on air shock and coil may not always feel as good. This is supposedly one of those where an air shock coupled to the design is said to have a very firm and efficient pedaling platform.

However having rode this bike with its stock air shock and another brand of coil shock, it certainly felt ok for both air a nd coil. The other coil shock left a lot to be desired though. With fully open compression settings, the damping still felt too stiff for the bike and no matter how the rebound is tweaked in relation to the compression-- the bike just keeps kicking up in the rear.
 
All of these gives a good idea for comparison when swapped out for the Dueler FR. Objectively it could also be attributed to just the coil itself. The 400lb steel coil of the last shock might not have been all that close to 400. Definitely felt a lot harder compared to the Kronos 400lb on the Dueler now.

As far as various brands of coils goes, be it steel or titanium.. the DSP Kronos has always felt to be the most accurate. I say "felt" because I have no access to actually test these things, so will have to let it rest at that. But given their published data of +/- 1.5% tolerance its the tightest range in all brands I have seen.


Difference was immediately noticeable. No "dead" feel. My earlier concern that the 400lb coil might be too stiff quickly dissolved. In fact with the Dueler, it actually sag  more than expected (~40%) giving rise to a new concern-- Bottoming Out.

Only 400lb or 500 lb option--where's the rest?
Based on the feel of the previous coil shock and some calculation I had originally requested a 350lb spring but was t/old only 400 and 500lb are available with the Dueler FRs...not too sure why as the bigger Duelers can be ordered with a ti coil range from 250-500lb. 

40% is a lot of sag on a 5.7" trail bike but with an efficient pedaling platform design there was no noticeable squatting even when gunning hard on the pedal. And hard it was, because it was practically a non-stop pedaling the entire time, catching a break only in corners and small jumps.

The test and thoughts...

Down and Popping
Great traction by the Dueler in combination with the 2.35 Schwalbe Hans Dampf even in the entirely wet ride. So much so that it was actually the front that washed out a couple of times. Firm spring on the fork isn't exactly what I normally use so not gonna fault anything here...a little more time to set up the front and things would certainly have been a lot better.

The trails had some small features, when taken at speed it gives a couple feet drop with one to 1.5 bike lengths going forward. Nothing big but enough to test impact on landing...

No hard bottoming out of the shock. Given the significant rear sag, a couple of hard thuds was expected. Granted the huge signature rubber bumper on Duelers would have helped slow things down quite a bit towards the end of the travel, still it is not very common to get this amount of rear plush compliance without having to worry on heavier hits. Can't entirely say if it one or the other but it wouldnt be too much to say the tuning on the Dueler on this particular suspension design is a perfect wet dream ride comes true.

What I think is a signature and central piece in all Dueler shocks that at first sight seems to take away a good portion of travel on the damper rod.... Rather understated but in all my ride experience with them-- a very crucial piece that helps control the last inch or so of travel on the bike. Not some uber hard rubber meant to simply stop the travel preventing shock body and lock ring knocking into each other. This actually compresses all the way down to ~0.25" which in the process helps to ramp things up nicely at end of travel to prevent harsh bottoming out.

One thing omitted was to check pressure in the piggy resevoir. It should come default from the factory at 150psi though. If it is, then for the first time I actually have a shock that is literally "plug-"n"-play" right off the start.

Up
Taking it through the climb, like any coil shock vs an air can between the legs, that quick snap to propel up and over obstacles are normally lacking in coils. While that is true but this is where the traction mediated in part by the shock shows up positively. Supple enough to bite down, enabling the bike to claw up and forward but not too much of that "sucked down" feel that's energy sapping. The rear was munching up square edges and rocky clumps with nary a kick. Something that otherwise my sit bones will be in vehement protest. Overall climbing feel was significantly light and surprisingly easy on this 15.5kg rig running coils on both ends.

One other thing to note.. The low-speed compression was set to fully open during the entire ride... On another drier day will try cranking up some lo-comp to see if there is enough firmness to gun through the slopes a la singlespeed mode.

Everything seems good with the Dueler FR at this point but I would like to find out if there are things that can be improved. The test so far might be on a suspension design that gels well with the particular tuning on the Dueler. Objectively it would be good to test it out again on other suspension designs, maybe a DW and some multi-link SP to reconfirm some of the thoughts so far. So stay tuned...

Twas actually more than just the Dueler FR shock testing on Sun.. A double bike test running  the same trails and sessioning various places on both bikes. Lots of good cross comparison data gathered.. but more of those thoughs on another write-up.

Diverse Dueler

The painstaking homework paid off for hunt of the front end suspension with the Vengeance HLR. So the last piece of the puzzle rest with replacing hopefully what is an almost 2 year old rear shock. In a market dominated by a few key brands, it's not easy to find a good product that withstand the rigors of modern day mountain biking. Pitting head on with the best or even outdo the performance of some of the Big Boys' models but yet remains well priced.

El Cheapo was adamant to find options to the "Cheaperest and Betterest" components; in line with one of the main intention behind this blog. A By Rider for Riders approach to help as many who are interested in this sports of ours but sometimes not knowing where to look.

From the pictures circulating around the web, frankly speaking the Diverse Dueler was not some love at first sight find.  But I do have to say that no others comes close when it narrows solely to just the "love" on the price tag.

For a coil shock under USD400 (then when I was looking), with one of the industry's best, Diverse own DSP Ti Spring, nothing comes close. The price is even lower now but recently it seems they are only selling to distributors and not to end customers anymore. As usual, with Dirty around, no worries, I always get my toys somehow. Now that I have gotten my hands on the actual thing, the odd mixture of "industrial-looking-slapped-with a la designer-cursive-fonts" actually looks quite good. No rainbow mix of colors on the knobs is a plus for me... adding to a no non-sense look if you are into that sort of scheme for your bike

Close Up and Specs

Shock finishing on close up looks nice with thick anodizing (those you know at first glance that would survive more than a few superficial knocks and still remains intact for the lifetime of the shock)

Very snug fit with the coil on both ends with the stopper and preload ring.  Stopper ring is machined with a recess that fits to the bottom out bumper, making everything more secure.

A rather long but soft bottom out bumper that makes a difference whenever you get to the bottom of a stroke. Probably contributes to the "bottomeless" feel I had while testing it out. Bumper end that comes into contact with the damper/seal area has some raised bits. This looks to prevents the bumper from slamming into and damaging the shaft/seal area. Nice touch!

Size of the piggy  resevoir is neither too small or overly fat like some others on the market-- any coil users would know the associated bane of a fat piggy that is too close to the coil or one too small and takes forever to fidget and dial the shock in properly.

PRC Adjustment, not available on this 8.5 x 2.5 size (only for the longer 9.5 and 10.5" sizes)
Hi & Low Compression involves separate Circuits. No clicks but with ~2.5 full turns for fine tuning
Adjustable Rebound. It is known that there are various rebound needles and I have asked for a slower one. Again non indented and has a total of 7 revolutions for tuning

Pedal platforming on the Dueler-- None, in any case my take has always been that if a shock is properly designed why bother with platforming! Compression adjustments would be more crucial and whether these works are more importantly than another dial to lock things back into "hardtail" mode which doesnt do squat for needed traction on the trail.

Plastic sleeve on shock body included. Nice little touch as coils tend to knock on the shock body creating ugly marks and indentations. Many of us have DIY with heat shrink or inner tubes to protect this area in the past. Nothing needed to be done here. With mounting hardware pressed in.. its plug n play without further ado.

Weight: Pretty impressive. Under 700gm with a 400lb x 2.5" DSP Ti Coil (including eyelet bushing but no mounting hardware). Complete shock alone including hardware but without spring is 413gm. The few extra grams on the stopper ring with the machined feature to seat the bumper thus helping to secure the ring. Something gladly welcome to reduce any unwanted movement as the bike starts pounding away.

 

First impression after examining is that being a supplier of coil spring for other makes of shock--I guess they have the benefit of making everything fit nicely and working out the little nuances as opposed to just most shocks fitting on an aftermarket spring only worrying if the OD matches their shock.

"Static" Impression

First few words that came to mind is reactive, stictionless and lots of sag which actually led me to an "Uh Oh" moment.. I  used an old Diverse 400 lb spring from my existing shock (and kept the shiny new one...err shiny?)... it felt distinctively softer and I was wondering if I should have gone one up to a 450lb spring in the first place.  Seems like the degree of valving is definitely very different. Having gotten used to the firmer feel of the DHX, it was worrying with the new found plushness on the Dueler... "How will it corner? Will it lose speed as it sucks the living daylight out of my 6 inch rear travel?..." are just some of the things that comes to mind. All of these were just the initial impression of sitting on the bike with the new shock and already feeling a whole load of differences without a pedal stroke.

These worries are valid, While not rocking a full DH bike but a 36lb 6x6 full sus is no weenie skinny either and if there is too much wallow, any chance to keep up with some of the XC boys on my usual rides would be next to impossible.


Initial dialling-in and ride impressions
after checking up the Diverse site for the shock setup, I decided to forgo those guidelines as it seems to be geared towards the bigger DH sized shocks by starting with Hi Comp dialling. Picked our favorite local rooty trail as the day's testbed, the initial Hi and Lo comp were set to 50/50% and rebound at a slower 40% from full out for my 76kg geared up weight.

While the shock is very reactive in the first half, the small bump compliance at this setting was nothing to rave about..in fact much like the old DHX it just replaced, Or thats what I initially thought.... a kilometer in and a few tweaks later everything transformed.

Try stepping out of a Cessna into a F15 fighter jet (ok fine fine, I'll admit, have never flew a plane in my life). Reduced the Lo comp and drop the rebound further to ~35% from max. The bike now eats up every piece of root, small rocks and trail irregularities. This despite tire pressure being higher than what I would normally ride (from the night before when hopping on concrete flats and not remembering to dial down to the usual trail riding pressure).

Not quite believing how different the bike feels, I kept going back after a few particularly nasty sections and pedal through them again and again. It was always the same, foot not missing a pedal and on a few bigger fast hits, there were no sudden spike that throws the bike off. This would be attributed to the Hi Compression doing its bit.

The internals of suspension are still a mystery to me just as I have said a few months back with a fork review. But at least after some reading up now, its not too hard to guess what went right or wrong when testing these components out. Certainly a lighter valving relative to my old shock is producing wonders with the Dueler on the EG. As to whether a thicker (12mm diameter) and lighter alu damper rod helps to make that difference is really beyond me. After checking the factory piggy shock setting, I pump it back up to 150 psi, close the cap and didnt fiddle anymore on the trail.

While resting in the shades after three run on the same trail that got progressively faster... it dawned on me that the initial "Uh Oh" worries had not manifested. Sure there is more sag on the same spring used. But my pedals have not sunk any lower on power strokes. Otherwise those dreaded pedal strikes will be apparent on a few particular spots on this trail.

When running through the straights at some point..I can't recall any squelchy squiggly feeling. If anything at all the pedaling was harder and going faster as small obstacles were "obliterated" underneath the shock. Being that reactive, "floating" the bike became much easier, rocking bodyweight fore and aft with alot less effort to get a good flow. With the rear having a mind of its own and doing it right, I had to up the compression on the fork while downing the rebound there by a tad. After that the suspensions were "talking" to each other again.

Did I mention that the rain decided to follow me on this day and with higher than usual tire pressure...I experience much lesser slipping and sliding around. All in all, could only say that form follows function for this shock and it does what it was designed to do. Traction... but not at the expense of bleeding speed in the turn as it compresses further into the travel. If anything, it pops out to  give a boost of speed but not with a quite sudden feel as to throw me off the bike. Still cannot figure how it gets so plush yet does not bob and bounce even when standing to mash up all the irritating short but steep rooty climbs around here.

Its a known fact that one of the chief complain on the Horst Link design is the kick going over square edges. Experiencing this on the climbs even at slow speed means throwing the traction off and could mean the end of a climb with a foot down on terra firma. This is something I have adjusted to on the DHX with quick weight shift when judging one is about to get me and overcompensates with a rather slow rebound.

With the Dueler.. there were deliberate and of course those rider-skills-really-sucks moments when I took bad lines ramping over rocks. The bike behavour with the Dueler exceeded expectation....clearing all but one really bad line taken. Even that didnt have that dreaded rear kicking up. Just too steep for my quads to overcome the jutting rock in a fatigued state.

Coming down? Yes, this is a 6" bomber build after all and so its important the shock has to be good on the descends. Despite all the "where is the bobbing and wallowing?"  I can't help but feel like wanting to just pull out a loaner 450lb shock, one up from what is in use and swap it there and then. As it turns out, it wasn't needed. just like on the straights and up...everything was just floating and throughout the higher speed descending sections with small drops, there wasn't a feeling of bottoming out or at least no sick end-of-travel- thud. On this last point, would have to add that it complements the slightly progressive aka rising-rate linkage curve of the EG's towards the end--much less harsher than the DHX or the original RP23 air shock.

Bunny hops from flats, and I mean the real thing, not bump hops or pulling up over an obstacle while  swishing through narrow windy tails  is something I thought wasnt very applicable during rides. Most time it requires a slow down and perfect execution. Good if your friend is snapping away so you can post up on facebook later with some "Yea that was me" smug pic to show off to the world. But after getting used to this new found reactivity and float with the shock, it was much easier to just air and let fly over foot high stuff that's usually just rolled over. So yes it rides faster better and sure is hell of a lot more fun on the trail. If I havent borrowed the term a "magic carpet ride", will  just add a twist to that because each landing (small ones, <3' so far) has this magic carpet landing feel to it as well. One last thing not tested out would be the popping off purpose built jumps and drops...something that would soon be done though.

Overall, I only have 2 niggles. The 2 compression knobs are a little small and tight to twist. While there is no frost bite to worry about taking off gloves to tweak those on the trails here, still, wet sweaty fingers trying to pinch a little knob is a bit of a pain. Secondly, it wouldnt be too difficult or costly to have the PRC adjustment on the piggy for all sizes. As pictures of it show, it is something that could be quite easily twisted by hand with more contact points to grab..it could be the ticket to a fast tweak on the trail with minimal fuss and makes for alot more happy riders with what I personally feel is an otherwise incredible component by today's standard of rear shock technology.

Simple and actually works.

Changes

Time to dust off the Soma... and make a few long overdue swaps. Back to the Nitto Randonneur. Monster 62t ring swapped to a spanking new and shiny 53t salsa. Rear has gone back to a 16t WI. Gonna miss the feel of the 18t trials freewheel :( Not much of a choice...ratio on the 18 with a 53 just overspin too much on the generally flat terrain around Coastal on those night rides. Need the most optimal gear-ratio if I hope to catch up with the bunch that's just gone faster these days.

EG is up for some changes too.. A Vector HLR rear doesnt seem to be materializing. Decided on a Dueler instead. While waiting for the piece to arrive....meantime slap on a t-loan and gonna test out both the 400 and 450 lb spring I have with me this Sat.  Thot the DHX was "perfect"-- not so sure now after  a cursory ride on the Dueler tonight. But not making any hasty decision, only a few proper trail rides later will tell.... oh please fast forward to Saturday.

No more ugly blue ano knobs, piggy cylinders or other stray ano hues Finally a true black-silver steed with just a minute amount of red accented bits spread out in the right places.

Jul 2011... back to the SOMA tweaks... lesson from the EG = reduce reach. I really just am not so lanky and tall!  Tange zero setback post. Nice blingy bling