The lowering of the saddle post clamp and opening of the seat tube allows the seat post to flex and absorb shock. It does work pretty effectively. I have a 2016 Diverge with the CGR post and this definitely is more compliant on the rear.

Interesting feature: with an oversize seat tube above clamp, I assume it's only there at all for greater esthetics– i.e., Specialized has provided a bit longer CF seat post for greater flexibility but wants to avoid the look of a lot of exposed post. I definitely can appreciate the fact that Specialized has designed around having the more traditional clamping arrangement for the end of a segment of slotted CF seat tube that extends above the top bar (my OCLV Pilot was designed in the traditional way which I was perhaps always overly solicitous of).

I ended up ordering a 54. i'm 5'10" I tried both back to back as well and the 54 felt better to me. i'm size 43 in specialized shoes. I hope I didn't make a mistake.

It will depend on your inseam measurement, and personal preference. Even though I'm slightly shorter than you, I have a 34"+ inseam, and large feet. Smaller frames tend to end up with lots of saddle to bar drop (due to shorter head tube), and more toe overlap. Your measurements may be completely different.

Of course, it also varies greatly according to bike geometry. I had a 54cm Trek Crossrip that was fine because of its long wheelbase all tall stack measurement.

i have about 31 inch inseam so longer torso and arms. the lbs fitter put me on a 54 and 56 tarmac because they had no roubiax. He was looking at the geometry of both bikes but said i looked better on the 56 because of my longer torso. I went to a different shop and tried both the 54 and 56 and the 54 felt better. but than again this is my first road bike. The lbs i ordered from said i will be fine either way but 54 will be more agressive and 56 more relaxed. thanks

Most everyone has a bike on which they couldn't go any smaller or they'd have been considering an even smaller size to begin with... and, if they'd gone to the larger size they'd have to tweaked a few things to make it a bit 'smaller.' So, choosing the smaller frame is never much different from those who buy the largest frame because they don't come bigger and do whatever may be necessary if they want a bit more room. My experience is that most lbs fitters probably consider themselves pros and between going small vs. large and making whatever adjustments are deemed appropriate to get a good fit, they always go smaller...

My base model came with Axis Sport wheels that were replaced under warranty about 2 weeks later. It was due to the rear freehub seal causing a binding issue that my LBS couldn’t figure out, so they overnighted a set of Easton EA70 Disc as a replacement. I never weighed the bike before the wheels were replaced the guys at the shop said the Easton’s were “over a pound lighter” than the Axis. Currently the bike weighs 9.18kg with 30/32 Roubaix Pro tubeless tires, 2 Specialized Ribcage cages, Ultegra pedals and a Fabric Scoop saddle. Strangely my frame has 10r printed on the chainstay...the $1900 base model is supposed to be a 9r according to the specs. This winter I plan on upgrading the drivetrain, so I’ll have to weigh the frame when I strip it down and maybe solve that mystery.

Thanks! :thumb: Yeah, definitely give one a test ride if you get a chance, but the SL4 is still a damn good bike!

2017 Roubaix Comp 56 impressions
 

I've had my 2017 Roubaix Comp 56 for 6 weeks/1000+ miles. FWIW I'm 5'10", 31" inseam and the 56 fits me very well. Didn't even intend to buy a new bike (old one was waiting on hub parts at LBS) but the 75 mile demo ride across 2 afternoons impressed me so much I bought the demo bike at a nice end-of-season discount. Soooo much less physical discomfort everywhere - lower back, sit bones, neck, and shoulders compared to my well-worn 2005 Sequoia Elite. And no numbness anywhere. I estimate 85-90% less overall discomfort, no exaggeration. It has made riding a pleasure again instead of a pain (pun intended). I even test rode an Elliptigo in search of a less painful exercise solution but it just wasn't for me.
The bike tracks straight, pedals easily and climbs well. The "bobbing" when climbing folks have asked about does occur but is not distracting or destabilizing in any way for me. IE its a non-factor on the negative side and a huge plus on the positive. The dual seat post technologies work pretty seamlessly. On bigger hits I can sense the compliance but if I didn't know it was there and how it works I surely couldn't tell you what its doing.
OEM Turbo Pro 26's lasted ~1500 miles (estimated due to unknown Demo miles, I put on 1155) and I just replaced them with 28mm Conti GP 4Season's for the cold weather months. Max spec tire width is 32mm but I personally think 28 is plenty of width and for warm season riding I'll probably go back to 26s or 25s. The bike has enough compliance that increasing tire width in search of more compliance is unnecessary IMHO.
While I cringed at the price (even discounted, yes I'm tight) I have to say this bike is much more than I imagined a bike could be. Tried to upload a pic but I'm a noob here and apparently don't have the required permission yet. Maybe later.

Added pic for previous post 2017 Roubaix impressions
 

This is the carbon/orange/charcoal color. I picked up the Road Kit (bottom frame triangle) half-price from another rider. Have a custom frame bag ordered from Rogue Panda to replace my well-worn Jandd.

Sweet! That rig looks ready to just eat the miles right up. Love that color scheme. Do you like the Contis better than the Turbos? Next spring I am going to switch my tires to either the Corsa G+ 28’s, Turbo Cotton 26’s or some 4000’s. If Conti made them in a tan sidewall I’d have those in a heartbeat.

Good looking ride. Glad to hear your comments on ride comfort, mirror my own.

Roubaix tires
 

I've only got ~100+ miles on the 4Seasons over the last 3 days (39-40F in Iowa) but so far so good. Settled in at 85/90psi. The Turbos felt lighter (90/95psi) even though they spec the same 250g, but of course they were getting progressively lighter due to wear. I expect the Conti's to wear much longer, perhaps 4k vs 1.5k based upon rider reviews. Glad to have the 4Season rubber and a bit of extra width/traction for the cold season.

New Roubaix weight
 

2017 Roubaix Comp 56 with Shimano 540SPD pedals, 2 btl cages (empty), and Urban front light = 20.0# on my bathroom scale. I think spec for the bike alone is 19+, which presumably includes the OEM flat pedals and reflectors, that were removed by the LBS before I rode/bought the bike. So spec wt seems credible and consistent with my observations. With frame bag+seat bag+contents+taillight (4#) and 2 full water bottles (3#) = 27# ready to ride.

I installed Hutchinson Sector 32 tubeless tires yesterday. They lost about 10lb of air overnight and maybe 5lb while commuting today. I understand that tubeless tires can take a day or two to seal up.

In any event the tires might be better/lighter/etc. than the 32mm Gatorskins that I was running but it is hard to tell.

Update on my 2018 Expert. 132 miles 10/31, 164 miles 11/2 and 202 miles 11/4 split, first 101 on 2013 Giant Propel Advanced SL then 101 on Roubaix FEELING THE LOVE of the Roubaix within 10' of leaving driveway. 104 miles last Saturday. Sunday is 100+ miles of Horrible Hundred in Clermont.

Keep us updated. I am interested in tubeless. What holds me back is it may be problematic getting them off to put a tube in if they fail.

Got a fit on mine. I haven't had the chance tor try it out yet though. Weather and time commitments are not cooperating.

I have a pair of Hunt AeroLight with Schwalbe One Pro 25mm (measure 26+) on my 2017 Comp as my "good" wheels. They are fantastic so far.

28mm Clemente LGGs (with tubes) went on the stock wheels as a training/winter setup. They measure about 28.5mm. I may try converting these to tubeless.

The stock Turbos have about 2k on them. I cut the rear on gravel & made a bit of bulge (no flat, though). Decided new ones before winter were in order.

My rig won't accommodate current 28s if they're actually more like 30s when inflated to 100 psi but, I guess it's not a problem since my 25s are really more like 27.5 at 100 psi. I think the size-inflation of current clinchers is a modern phenomenon. I remember my old 23s not looking any larger than tubulars.

My 2017 Roubaix Comp will clear 32c Panaracer Gravel King SKs. The tight spot is either the seat tube or the front derailleur arm, they both look to be about the same clearance. Sloppy picture:

Speed results, Sectuar vs. Roubaix
 

I have a few hundred miles on my Roubaix now.

I bought it primarily because I hoped that the FS and wide tires would tame the nasty chipseal on the roads. Especially
on my longer century rides. I've been recording my times over one particular road segment to track progress.

The segment is "The end of crappy road" located near Newark, CA. About 1.2 miles of really ****ty potholes and chipseal.

Speeds are as follows:
1. 2006 Specialized Sectuar with 28mm Gatorskin tires 85PSI 16.4 MPH
2. 2018 Specialized Roubaix with 32mm Gatorskin tires 80PSI 17.1 MPH
3. 2018 Specialized Roubaix with 32mm Hutchinson Sector tires 70PSI 17.7 MPH

Ride 1 was during my peak Century fitness this summer. Ride 3 was done after about a month off due to pneumonia, so not at peak performance.

Anyhoo, about an 8% improvement on the roads where I suffer the most.

I set a bunch of PRs on my other routes as well but I do not track them closely.

2018 Roubaix and Hutchinson Sector 32 tubeless
 

I've been using Gatorskins only for years now. Before the Gators I was getting 2 flats a ride through the crappier areas that form my routes. With the Gatorskins I got 2 flats in 5 years. However, the latest flat was Goathead through the main armor belt of a brand new tire, out in the boonies, during a Century. It was easy to change and fix but enough to make me look for alternatives.

I've been thinking about tubeless for awhile but was put off by the general lack of rigor and standards. Road UST seems to be the only standard that can approach the hands off car/motorcycle like maintenance that I want. However, Road UST is encumbered by patents and the various manufacturers have half-assed their way around them.

The Hutchinson Sector 32 has an armored belt and the profile is close to UST. Similarly, the Roval SLX 24 wheels are close to UST as well. So, good enough. I plan to move over to UST if/when Mavic et al start shipping wider wheels and tires.

My initial assembly was a comedy of errors. There is no agreed upon standard for machining stem surfaces, proper o-rings, or any of other engineered approaches that I am used to. With road tubeless you just sorta tinker about until you find something that seems to work. It annoys me.

The original Stan's stems were too small to seal and I managed to pull one through. Put the Gatorskins back on and ordered their oversized stems. I also glued the stems with a bit of contact cement.

This is what the (blurry) Stan's stems look like. The small scratches are from my earlier attempt of trying to seal the tire with the standard stem.
https://www.bikeforums.net/attachmen...1&d=1511292494

If I was doing it again I would try the American Classic Stems. Their usage of captured o-rings is what I am used to using in automotive and high pressure applications.

The completed wheels and tires look quite handsome I think. It was a muddy and chilly Century yesterday.
https://www.bikeforums.net/attachmen...1&d=1511292651

These 32mm tires measure 31.75mm at 70 PSI
https://www.bikeforums.net/attachmen...1&d=1511293159

There is about 2.5mm of clearance up front. I might be able to fit a 35mm.
https://www.bikeforums.net/attachmen...1&d=1511293553

"Copious" room out back. Maybe I can run a 40mm?
https://www.bikeforums.net/attachmen...1&d=1511293397

They work well. I've been running 65/75 PSI F/R. They handle nicely and I barely notice the various bumps and whatnot. With 23mm tires I was out of the saddle all the time. Now I just glide right over.

I did get 3 punctures through a really bad industrial area. Didn't even notice until this morning when I pulled out a staple. The sealant sealed things right up. Very nice. This is what my floor and the tire looks like.
https://www.bikeforums.net/attachmen...1&d=1511292981
https://www.bikeforums.net/attachmen...1&d=1511292981

There is another sealed hole in the rear tire, and third puncture in the front. I'm not sure that my old Gatorskins would have flatted but I am glad I was not on them or a less durable tire.

In summary, still grumpy about the lack of standards, happy with the performance, really like the comfort, and I would do it again.

Oh yeah, "The end of crappy road" :) I'm still hoping they'll repave that whole back road! So far (as you probably know already), they've only resurfaced part of it close to the bridge, and only westbound...

I'm used to it with my SL4 Roubaix, but it's a bit more comfortable with the 2016 Diverge that's for sure! I'd love to give it a try with the FS. Actually I take that back, I don't want to, or else I'll need to buy another bike LOL

:beer:
Geoff

My Roubaix, purchased a few months ago after my Allez Sport was stolen. When I ordered it the wife had misgivings about the coloring, but I love it. I think it’s extra visible from a distance and I get lots of compliments. :)

I’m 5-11 and the old bike was a 58, but this one is a 56 and I like the slightly smaller frame. The odd looking lock under the frame pack is a TiGr titanium, just weighs about 1.5 lbs. Next to the bell is a Garmin car GPS that I’ve adapted to the handlebars, with a big battery that will run it for about 12 hours.

This bike has been fantastic — it’s definitely faster and more comfortable than the Allez was. As far as I can tell, the Future Shock works really well. It filters out the little bumps nicely and doesn't seem to reduce efficiency. Last weekend I rode from Santa Barbara to Burbank, 103 miles. I did a lot of shopping around and considered many models before settling on this — all the positive comments on this thread were a big factor in the final decision. Very satisfied.

http://wwww.dkse.net/david/DSCN4066a.jpg

Nice pics 3949dxer. What are your strategies around the frame bag?

https://www.bikeforums.net/attachmen...1&d=1511491452
Here my latest build out. I am tempted to add another 2 bottles behind the seat, and replace the seat bag with a bento of some sort. I found that after 100 miles the seat bag chafes against my leg just enough to cause ouchies.

The bicycle pump is leaving too. I used it while getting used to the tubeless tires but am confident enough to leave it at home now.