Greetings,

I'm looking for some wisdom from this community. I am ready to purchase a bike and have been looking at the Roubaix, until I saw the CruX, and now I'm on the fence. I know it's an odd pair, apples and oranges, and so on.

Objective: Comfort, endurance, more upright riding position (back pains).

Why Roubaix? I'm a geek--I like the idea of the Zertzs. It looks plush. I want an all-carbon bike to go with my all-carbon mountain bike.

Why CruX? I occasionally ride on dirt, bad roads, gravel, and the 2011 CruX has Zertz. It's nice to have the option of larger tires and jumping off of a curb.

I am here to ask strictly about the frame/fork geometry between the Roubaix and CruX. Although they appear different, they seem to end up having a very smiliar net geometry. I have read about head tube angle, head tube length, top tube length, reach, stack, etc. for comfort, but it's difficult for me to decipher all the data.

If, considering the same size of Roubaix and CruX, comparing the frame geometry, which bike will provide a less reach, more upright, and therefore, comfortable for me riding? I read that the Roubaix is more of an endurance, all-day bike, but if the CruX has a similar net geometry and can accommodate larger (more plush) tires, would it also fit the bill? (I ask because people tend to talk about CX bikes as the "one hour at a time" sort of equipment.)

Many thanks for any guidance (after you roll your eyes at the thought of this comparison :-) )

Cheers.

You have asked a lot of questions...good questions tho.
Can you read a geometry chart? Compare stack and reach on the Roubaix to the Crux. Post charts if you want here. FWIW a Crux has 30mm or so longer fork crown to axle to fit taller + wider rubber but has a much shorter head tube...different fork rake and slightly less BB drop aka higher BB.
There is about a one size equivalency difference. A bit odd but that is how the convention turns out if you crunch the nos. A 58 Roubaix has almost identical stack and reach to a 61 Crux.

Now...the difference in the bikes. It all depends on the ratio of dirt to pavement you ride. If you spend 80% of the time on pavement, get the Roubaix. If you need to, you can run 28c tires on a Roubaix. Its a faster bike than the Crux on pavement, climbing and smooth dirt. If you are going to ride rougher dirt, mostly single track or gravel, get the Crux.

Btw, the Roubaix is far from plush. My SL3 is as stiff as the Look roadbike it replaced with even better power transfer. The SL4 is even closer to the Tarmac in stiffness.

Either bike is great. A Roubaix is a very versatile road bike and a carbon Crux is a very nice carbon cross bike that can handle the rough stuff even better but a penalty on the smooth stuff.

The Roubaix sure changed over the years. I had a 2006 Comp and that bike was the definition of the word plush. So much so I didn't really care for it. I didn't feel a thing while riding it. While I've never rode a Crux, I have owned several Tricross bikes and I loved the versatility of the cyclocross bike. Being Aluminum, I figured it would ride as bad as Aluminum Trek's I've owned in the past, but it actually rode very nice and wasn't harsh at all. Guess it was the geometry.

While the Crux you can run larger tires, if you only run on gravel occasionally, I think the Roubaix would be a better choice. If it was true versatility I was looking for, I would go for a Tricross instead since it has rack and fender mounts as the Crux doesn't have them from my understanding. I think you'll find the Crux to be a touch less snappy than the Roubaix. That may or may not matter to you but when I was riding more spirited rides, my cross bike wasn't all that fun compared to my regular road bike.

I faced the same dilemma several years ago. I bought a Tricross (precursor to the Crux) because of the more upright geometry. My rationale was that this would be an easier transition to a road bike. Looking back, I should have got the Roubaix from the beginning. The ride difference between the Tricross and Roubaix are there. I believe the Roubaix edges the Tricross in all aspects on the road. With a custom fitting, a good pair of bibs, the Cob-l-goblr seatpost = a magic carpet ride. Good luck in your quest.

Regards,

BWJ

It really depends on your use I guess. The Roubaix is a great ride, extremely comfortable once fit to you personally.


the CruX...I can't say I've ridden one but I can say it is a apples-vs-oranges bike choice.


the CruX is for off road cross riding/racing, not really designed to be a "more comfortable Roubaix". The gearing is even off for real road riding (check out the front gearing for example).

If you want a comftable road bike, stick with the Roubaix. It will be a faster, better ride on pavement that the CruX. If you want more off road, go with the CruX (or better yet, an off road bike rather than a cross bike).

your post seems to me you want a road bike (unless I'm reading you incorrectly)...I'd stick with the Roubaix, it's one hell of a nice bike. I rode one all last season and loved it.

What one needs to realize about the crux is that it is not a comfort bike. It's for racing and so the geometry is for racing. Also the E5 alu model is really really stiff. Not sure about the zertz inserts.

If you want to get the crux on the road you need road tires. Not a problem. If you want to use the roubaix for gravel grinding it's not going to be optimal. GG is a thing nowdays so you might get into it.

About the whole one bike is faster than the other... well, they are different but none of the differences directly affect speed. Except of course the front chainring size on downhills. If you are a beginner you are most likely not going to spin out the 46/11 on flat. Then again the crux has a compact so you can just swap the chainrings to bigger if you feel like it.

Handling geometry is preference and if you are a beginner, well then you just don't know yet what you like. It might go both ways. The twichier roubaix or the more stable at speed crux.

Also the tricross and crux have different geometries. I can well understand that the tricross lacks fast handling but the crux is very snappy indeed when it needs to be.

Thanks for all the replies and great information. There is a lot to think about. Thank you all for not simply replying to a noob with a "duh".

I can read the geometry chart in terms of comparing the figures and interpret the obvious. But when it comes to understanding how all of the data tie together, how they affect the overall/net geometry, their implications between one bike and another, I'm lost without more reading.

I see the point about the 58 Roubaix vs. 61. Interesting. Looking at the 2012 data for the CruX and Roubaix, it was even more interesting to look at the 56 vs. 56. While both the 61 CruX and 58 Roubaix have the reach of 392mm, the 56 Roubaix has a reach of 387mm and 56 CruX has the reach of 384mm (in this case, the CruX is less). Why the non-linear progression between sizes?

One important question: Can a Roubaix with 28c tires withstand curb jump-offs (size 56 w/ a 160 lbs rider)??

Going back to a more specific geometry comparison, which of the 2012 would yield a more upright position? From what I can tell, they are very close. Am I right?

Size, head tube angle, head tube length, stack, reach
CruX: 72, 155, 583, 384
Roubaix: 72.5, 190, 589, 387
(Difference between head tube length being offset by ~30mm additional fork length in CruX)

Cheers.

Possibly this is coming from lack of experience...but pure frame dimensions often tell me zip about how a bike rides. I hate to use a tired saying, but riding a bike really is the only way to tell how it feels. Data sheets, sales brochures, manufacturer terms (OCLV, "10r carbon", etc)...all of those really do not tell that tale properly.

As for running a 28mm tire on a Roubaix...I'm not sure on that one. The Roubaix I spent last season on (2009 105) barely accepted the 25mm tires with the brakes all the way open. You may or may not be able to squeeze a 28mm in there...I'm not sure it will clear the brakes though (unless you get a disc brake model).

I guess I have to ask this...are you planning on doing much curb hopping? Perhaps I'm making an assumption as to where you live but in the central Illinois area, I've yet to have to pop a curb on my road bike and that's after 1000's of miles over the past year. Personally, I stay away from sidewalks and curbs, sidewalk to road transitions is something I just avoid.

Roubaix will take 28s no problem. The crux is a great ride but the one with zertz is an old tricross. i

So, something I'm a bit unclear on. Do you plan to:

• Ride on tarmac most of the time, and be prepared for the occasional patch of bad roads and gravel
• Do a ride that is 75% tarmac and 25% gravel, or 50/50
• Do a ride one day that's on tarmac, and the next day use the same bike to do mostly gravel

I got a SL4 Roubaix and a Crux Evo, if I were to pick one it would be the Crux Evo. Crux Evo is designed for gravel riding, it has hydraulic disc brakes and a compact crankset 50-34. I've ridden the bike in gravel, sand, dirt, mud, street and everything in between, the bike is stiff and I love it.

Thanks for the responses, in particular, pointing out the 2011 Crux w/ Zertz is the old Tricross. I now see that the 2010 Tricross has the same geometry as the 2011 Crux.

My typical path contains riding on the curb at times (long curb, no pedestrians, safer than street and better surface) and having to get off the curb where there is no driveway. It also contains poor roads and debris depending on time of year. I just want to have the ability to hop off of a curb without damaging the tire/wheel and was curious whether a Roubaix with larger tires can handle that. Roubaix was a consideration in the first place because it will help me keep up with my friends riding long distances.

If one were to consider the Tricross geometry, it looks awfully similar to that of the Roubaix from my read. Am I right?

In a nutshell, I'm looking for a rig that is light and efficient enough for me to go long distances, carbon, can occasional handle curb jumps, is upright enough to prevent my back pain, and Zertz are cool.

in that case a roubaix, with bomb proof 32 hole wheels. something like a 3 cross 32hole on ultegra hubs and Hed Belgium rims ought to work quite well..oh and get a fit to deal with the back pain side of things

Which if either did you wind up getting?