So I recently bought a 2013 Scott CR1 Premuim Di2 second hand. It was supposed to be an upgrade over my 2007 Specialized S-Works Roubaix. Having been on a few rides, and then switching back to the old bike, I’m not sure I made the right choice. The old bike just seems to accelerate and roll better. I’m slightly perplexed but am considering whether the wheels are the issue. The Roubaix has Ultegra with 25mm GP4’s, the Scott has Cerro AR30 with 23mm GP4’s. When I grab the wheel with my hand a try and move it side to side there is a bit more flex on the Cero wheels when compared to the Ultegra’s. I wander whether despite these wheels being lighter the reduced stiffness may actually be detrimental to acceleration and power efficiency? Any thoughts out there? I’m very close to selling the Scott bike! Maybe the frames is not as stiff also….I weigh around 88kg

Can’t you just swap the wheels over…and try it?

I guess I could although the cassettes will need swapped..one is 10 speed and one is 11 speed

although the cassettes will need swapped

Probably less effort than selling the bike?

In what way did you expect the Scott to be an upgrade?

You probably are feeling the the difference in wheel stiffness, which will feel like it’s transferring power down better on the stiffer wheel. Whether that feel actually results in better performance time wise is more the whole bike package imho.

I am a bit of a believer in compliance translates to an overall advantage compared to all out stiffness.

Fisha…I guess I thought it would be more efficient, newer, lighter design with improved drive train. Also a better fit (the roubaix is 56cm and slightly too large). Yes I’m going to try swap the wheels first.

For the sake of the time it’ll take to swap, it’s worth doing to see whether it is just the wheels or not.

All that being said the frame will be significantly different. I found it surprising how much difference there was between a trek Alu frame and a Klein one, and the difference from those to a carbon domane was bigger again. I felt the Carbon domane was dull to ride initially but overtime I do feel that I’m faster on the duller softer bike.

It’s more than just the wheels , but I’d guess that the swap will bring results closer to what you’re looking for f on the Scott

The Scott CR1 is widely rates as one of the stiffest road bike frames available. In fact many think it is too stiff for comfort!. It will be the wheels. Swap them over if you can. Cassettes are a two minute job. Check the limit screws when you have.

I’ve recently swapped from a Ally framed bike to a GIANT Propel, a bit of a night and day scenario for me as the Propel is Full carbon including Deep section wheels. There seems to be little or NO give in either the frame or the Wheels.

First thoughts were pretty much the same as yours………… OH Fooook what have i done, The first two weeks i pretty much gave up on it as i just couldn’t get my head round it and just felt awkward. Not only that i was no faster on the thing than i was on the Ally framed 27mm tyred behemoth.

I had a fortnights Holiday and when i came back i’d kinda forgotton the Ally bike even existed, i’d forgotton how to ride it and instinctively found speed on the Propel where before i was just lost on it. I also put some Vittoria Open Pave’s on it in 25mm which instantly changed the ride and feel.

I’m now a lot faster than i was on the Behemoth, but looking forward to dragging it out for the winter.

Stick with it, And change the tyres.

Won’t be able to swap an 11 speed cassette onto the Roubaix’s wheels unless they’re very recent Ultegra.

Njee20…I guess the wheels are about 5 years old…

Just swap the wheels and cassette and stay in one gear, select the right gear to test with and go and try a few corners to test the wheel deflection.

I should add that there is a slight rattle from the rear if the bike when putting the power down which I have been able to find the source of.

I thought it could be a spoke or spokes but when I check the tension by hand all seem quite taught.

Turnerguy…will the 11 speed chain work with the 10 speed cassette? I thought it was narrower..

Cassette (probably) won’t fit though.

You could leave off one of the middle gears in the 11s cassette to make a slightly narrow 10s one, might need to use a spacer at the back of the cassette or might not but it’ll fit and it’ll index as long as you wind the limit screw in.

What TiRed said. The Scott is meant to be a seriously stiff frame so I’d expect it to feel very different indeed to the Roubaix.

you’ll get a fair idea if you only swap the front wheel over. I put a spare front on last week after a flat, and the difference is very marked. From a 38mm section rim to a 24mm carbon with about 3 spokes.
I know a few lads with the CR1 (LBS is a Scott dealer) and flexy is not an adjective I’ve heard about them. I wonder if the lightness of the new bike is making it feel less direct under power than the Sworks, if there is indeed much difference in weight.

Turnerguy…will the 11 speed chain work with the 10 speed cassette? I thought it was narrower..

It’s the outer plate width that is narrower. The inner width is the same.

Just put it in one gear, adjust the chain line, and then go for a spin.

leaving aside everything else for a moment…

The old bike just seems to accelerate and roll better.

have you quantified this or is it just a feeling?

seems =/= actually is

Quite often what feels fast/slow is determined by overriding external stimuli like geometry difference, vibration and buzz, and stuff like that, rather than you actually being able to detect minute changes in acceleration. So is the new bike actually slower or fatiguing you earlier or is this a perceptual thing?

Also, when you swapped back, was it on the same day or are there differences in weather, energy levels, route etc. that could have been affecting your experience as well?

And +1 for just swap wheels and test, it’s the obvious thing to do first.

I’m selling my Defy and going back to a CR1 SL because it’s stiffer and faster.

Just put it in one gear, adjust the chain line, and then go for a spin.

Do this and just see how it feels, or borrow some 11sp wheels from a mate for an extended test?

Thanks for all the advice everyone – I’m going to get the ultegra wheels fitted somehow when I get home this weekend and see what’s what. Or May end up borrowing some other wheels just to see.

As I think has been said, you can just use the 10sp cassette on the 11sp bike as the cassette spacing is the same on 10 and 11 speed. You just need to set the limit screws.

I thought the idea of the Roubaix was that it could handle rough surfaces but still transfer power well?

Hey all I thought I’d post back with the findings from my not very scientist test. So I went up the climb from my house about 3 times on each bike / wheel combo (much to the amusement of my neighbours). Here is what I found.

Bike – Wheel – Average Speed / Max Speed
Roubaix – Ultegra – 14.6 mph / 18 mph
Scott – Cero – 12.8 mph / 16.2 mph
Scott – Ultegra – 15.2 mph / 19.2 mph

This did surprise me given the cero wheels definitely feel lighter.

Sorry, but that test isn’t scientific at all (looking at the output data). The 3mph difference is way too much to be the result of switching the wheels – going from the heaviest, flexiest, non-aero wheels to the lightest, stiffest, aero wheels wouldn’t make anywhere near that much difference.

Aracer…yes you’re right it certainly wasn’t scientific…but at least backed up my gut feeling. A colleague thinks there may be an issue with the bearings on the Cero wheels? They seem to spin well freely and there isn’t really any play. There is a bit of a rattling sound under power which I can’t pin down.

The trouble is, there’s clearly some other factor there affecting the results which is completely masking the real effect of the wheels. So you can’t draw ANY conclusions about what difference the wheels are making.

but at least backed up my gut feeling

You may be confusing cause and effect here.

A friend of mine who got some Cero’s said he didn’t think they felt that great either. They have quite small bearings don’t they and low spoke count? 88kg rider weight might just be too much for them.

But as per other posts, there is no way a wheel change could result in a 2mph difference!

Mtbtomo..yes they are lower spoke count, don’t know about the size of the bearings but the overall assembly isn’t as beefy as the Ultegra