zerokoo149

I do a lot of mountain biking on the weekends, but during the week I like to ride road since I can just walk out my front door and be on my way. I have a 30 mile loop that I ride often for the past few years. When I first started, I was riding a 56mm Felt z80 that I got for free from a friend. 2 weeks ago I decided to upgrade and bought a leftover 58mm Specialized Roubaix after being properly sized by my LBS.

So far in the 3 times I've ridden the 30 mile loop on the Roubaix, I'm consistently 6 minutes slower and my legs feel more tired by the time I get back to my house, I also never really noticed my legs being tired on the z80. The cockpit on the Roubaix is considerably more comfortable, probably because it's properly sized, but taking that much longer on the ride is driving me nuts. I've checked the wheels and drive train and can't find any drag. I can't get to the bike shop for them to take a look until this Saturday, but was hoping that I might be overlooking something that someone could point out.

Here is a link to my old z80 (56mm):
Felt Bicycles USA - Z80 (8927)

Link to my new Roubaix (58mm):
https://www.specialized.com/us/en/bi...ora-disc/50911

Thanks in advance for any help,
Russ

DrIsotope

Fit.

Homebrew01

Fit (more or less aero)
Different weather
Tired, rested, mood............ so many variables

corrado33

If the new bike is more comfortable, then you're likely sitting up further, making you less aero. Aero is king once you get above 15 MPH on so.

Also, you may want to check how long the cranks are on both bikes. Often the switch from 172.5 to 175s is around the 58cm bike size. Perhaps you like the smaller cranks.

zerokoo149

I honestly don't know a lot about fitment, but with the new bike having a top tube that is 22mm longer, I thought that I would be sitting lower because of the further reach and be a bit more aero. Does that make sense, or do I have that part backwards?

Both the bikes have 175mm cranks.

wphamilton

One scheme of having a more relaxed comfortable position has a longer top tube and higher handlebars, close to the level of the saddle. The effect is a more upright position. We don't know how your bike is set up, but that's one possibility.

Otherwise there are a lot of variables, some of which may change after you have had more rides with the new bike. I wouldn't blame the bike just yet.

SquidPuppet

Saddle to bar drop is equal on both bikes?

Saddle fore/aft is the same on both bikes?

Bike weight?

Wheels/TIRES?

Hypno Toad

^^^^ tires!

And I'd a sample size of 3 is small. I find it takes me a fair number of rides to bond with a new bike.

02Giant 

Disc brakes dragging?

TheLibrarian

As everyone knows red is just plain faster and tastes better.

10 Wheels

Cheddarpecker

My last upgrade was heaven on earth for the first ride, pretty awesome on the second, and somewhat normal for the third. I returned to the previous bike and was shocked at how dead, slow, and rough it seemed. I probably put 700 miles on it and thought it was pretty nice. Never realized how much it was holding me back.

Of course, I set it up in the driveway to fit and made adjustments as needed. It really came alive with good tires.

HTupolev

That's not quite how it works. In order to pedal powerfully and efficiently, you want certain parts of your body to be within certain angles relative to each other. Making a fit more aggressive by extending reach tends to break this; simply leaning your torso down can make you more aero, but it also makes it hard to pedal.

The easiest way to fit a too-large frame to a rider is usually, roughly speaking, to raise the handlebars to them, making things feel fairly reclined. Track racers often use too-small frames because they easily get an aggressive fit.

Got pics of your bikes from the side, that show how the saddles and handlebars were positioned relative to everything?

Phil_gretz

I don't know what I'm talking about, so what I'm going to write may be complete bs. I don't know...


My most recent bike purchase is a compact frame with a long-ish top tube. Because it's "one size" smaller according to the manufacturer, the fit was a bit different than most of my other bikes, which are set up somewhat similarly. My commuter and tourer are both set up with handlebars just below saddle height. Very comfy for plodding along while carrying a load. This road bike has a bit more handlebar drop and requires that I ride in more of a tuck, which is kind of cool. In the drops, I feel that my back is almost horizontal, but of course, it's not.


But the notable part (for me) is that this lower position is noticeably more powerful because it brings my glutes and hamstrings much more into play. And I feel it when pulling hard. If I ride that bike to work for two or three days consecutively, I feel the effects of working those muscle groups more. Tightness, soreness, stiffness that has to be worked and stretched out. Not pain, and not an injury, but fatigue and tightness. These are good things, because it means that new muscles are getting some of the work.


Maybe the OP is slower because his pelvis is in a new position (rotation) and less developed muscles are in play?


Of course, aerodynamics are a big contributor to the impression of speed. But 6 minutes in 30 miles is what, 4-5% slower, give or take? Maybe more samples to smooth out the variables of wind or body fatigue...

MRT2

Depending on the speed, your average speed is around .5 mph slower on the new bike. I would take that trade off for more comfort over a couple of hours of riding, give or take 6 minutes or so, but that is me.

3 rides is not a big enough sample. I have ridden the same 30 mile rides and finished 10 or 15 minutes faster or slower riding the same bike. A lot depends on the wind. Maybe you were riding into more of a headwind or cross wind for those 3 rides. Or maybe the riding position really is less aero, in which case you will either have to train harder, get lower, or leave 6 minutes earlier.

BlazingPedals

I hope both of those are yours. If I had a classic like that and someone parked their bike against it, I'd kill them first, then pitch their bike in the nearest river.

Maelochs

Do you still have the Felt?

Leebo

Tires and psi? More coffee and less strava? Does it matter? I don't race so I wouldn't know.

zerokoo149

I didn't measure the saddle to bar or fore/aft on the bikes, but I would say the feel roughly the same. The handlebars on the Roubaix are 20mm wider which is very noticeable. I hands would always go numb towards the end of the ride on the Felt, and that doesn't happen on the Roubaix which is very nice.

The roubaix build is a lot lighter, and the wheels are also definitely lighter. The new tires are a softer material, so that could account for some speed loss.

zerokoo149

I can take some pics tonight to show the differences. As I think about it, you could be on to something with the downward leaning torso.

zerokoo149

Yes, still have it. Planning on selling it, haven't had a chance to yet.

bikecrate

The gears are slightly different - Felt: 50/39/30T, Specialized: 50/34. The rear cassette Felt: 9-Speed, 12-25T, Specialized: 9-speed, 11-32. Depending on what kind of riding you're doing maybe that is making a difference?

zerokoo149

Running the same psi, but the new rubber is definitely a bit softer.

I'm by no means fast, but I do track with strava. I had high hopes of going faster on the new lighter bike so that I could ride further in the same time frame.

Maelochs

Bar width might account for the numbness, but likely instead it is weight distribution--you were leaning way forward on the Felt and end up carrying more weight on your hands by the end of the ride because you legs and core got tired.

That one point makes me think that the Roubaix has you sitting a lot more upright--which means a lot more aero drag.

If the Roubaix is a lot lighter .... Hmmm.

Softer rubber isn't going to slow you down, it will let you corner faster and should roll about the same ... tire width and inflation also matters a lot. If you are sitting more upright (to be expected on a bike with a shorter top tube and taller head tube then it is unlikely that seat-bard drop and other dimensions are the same ... and a few centimeters makes a big difference.

Have you dialed in your fit on the new bike? I rode a lot of miles on my last new bike and it felt really great---then one day I realized I could raise the seat a little, and it made a huge difference in engaging my whole leg---and felt just as comfortable. I assume I had finally adapted the rest of my body to the bike's slightly different proportions, and when everything else was comfortable, I could finally feel my actual correct saddle height.

Same thing might happen with the Roubaix. Once you find your best set-up where your whole body works naturally, you might find some missing speed.

Other possibilities: The Felt is a simple aluminum frame, the Roubaix has those Zertz which absorb vibration ... which means there has to be some efficiency loss. Minuscule, perhaps ...

The Felt has a 3x9, the Roubaix 2x9. It could be that you could more easily find the perfect ration on the Felt, while with the low-geared, wider-range Roubaix you might be “between” ratios sometimes. (This review (Specialized Roubaix SL4 Sora review - BikeRadar USA ) mentions that: “There’s a huge gear range, with the compact chainset driving an 11-32 cassette. It’s debatable who needs that much range – and hard to imagine that a rider who needs 34x32 getting much use out of 50x11. It’s a big range to get out of a 9-speed cassette, too, giving significant gaps that make it harder to maintain an even cadence at times.”)

This review (Specialized Roubaix SL4 review - Cycling Weekly ) says “DT Axis wheels are heavy and flexy."

Also lists the weight (9.2 kg, 20.3 lbs) as pretty close (8 ounces) to the Felt (20.798 lbs.)

The Specialized is described repeatedly as having a comfort-cruiser sort of ride—maybe when you ride it you are more relaxed, feel more removed from the road, and simply aren’t trying so hard?

All the reviews I read said the bike wasn’t quick but was comfortable and perfect for really long rides. This review seems to think it is best used as a gravel bike (Specialized Roubaix SL4 Disc review | Cyclingnews.com )

What it breaks down to, I think, is that the Felt was a decent sports-car sort of bike, and the Roubaix is more of a sport-utility.

HTupolev

Soft tread compound shouldn't be an issue. If the new tires have stiff casing, that would slow them down. If the new tires have tread designed to dig into soft surfaces (like MTB knobbies), that would also slow them down.

How much lighter is the complete build on the new bike actually? Have you weighed them?

Keep in mind that people tend to massively exaggerate the impact of bike weight. To get a sense for the degree of impact: if you're someone who pedals at 150W, an extra kilogram on your bike is going to add in the ballpark of two minutes to the ascent of a 2000m mountain pass. On flat ground, it basically doesn't matter at all unless you're having to accelerate a lot, which frequently isn't the case on solo rides.