rpenmanparker 

Jen, I see two issues. First, your ultra short CC top tube recommendation just doesn't look right for someone your size. It is way short. Even women's bikes don't come with top tubes that short.

Second, after looking at the geometry diagram on the Bikes Direct web site, it looks to me like the seat tube length and nominal sizes both refer to the actual seat tube length, neither refers to the effective seat tube length (effective would be from center of BB to the spot on the seat post in the center of where a HORIZONTAL top tube would intersect or the so called "bike size". Looking at the picture of the slope of the top tube, I would say you need to add about 3 cm to the size to convert it to a conventional bicycle size. In other words, I think the actual "size" of the 51 cm bike is about 54 cm or in some carbon bike terms, M. That means the top tube is actually on the short side on this model bike, not on the long side, though not as short as a women specific frame.

Normally I agree fully with Campag4life, but at 5"4', I question whether you would properly ride a frame that would normally be called 54 cm or Medium (here it is called 51 cm) which at 5'8" is what I ride. Damn, I know this is confusing! It looks to me like the Bikes Direct "48" which in standard parlance is about a 51 or Small, is the right size for you. The top tube is only 0.5 cm shorter so it is still generous (relative to your needs) to stretch you out, but not crazy long. For a woman it is good this model has relatively short top tubes. You can make up for any small problem with stem length.

On the one hand I think you should consider what I am saying, but on the other hand I urge you to seek some confirmation. I could be absolutely full of bull, but I don't think so. If anyone gets agrees or disagree with my analysis from looking at the Bikes Direct geometry key and the slope of the top tube in the picture, please let me know.

Robert

Sabby

I will try that bike specifically and do as you suggest re the stem.

One thing, though...if I've not ridden a road bike in foooorEVeeeer (if you ever saw The Sandlot you should know how I just said that) then how will I know if I like it after a short ride? I live in the city so I can't imagine they'll let me just take the bike. I'll see.

Also, I've never in my life clipped into a pedal so I will be just riding it with my bare feet (or running shoes) on the clips, which isn't ideal. I don't think I'll get a good idea for how I like it if I'm focusing on learning how to clip in/out.

------->nooooooob<-----------

rpenmanparker 

Ask the shop for some platform pedals with or without toe clips and straps. They are happy to switch pedals. Many folks bring their own when buying a bike.

megalowmatt

Just to throw this out there because it's a big purchase...

I'm 5'9" on a good day and chose the 51. I normally ride with a total reach of ~65cm so generally I will ride bikes with 54cm effective top tube and adjust from there. I was originally torn between the Moto 51 & 54 but went with the 51 out of pure vanity and I knew it was within my range. I wanted to post this for sake of reference but I'm not a fan of being real stretched out, either because I'm old.

I'm not familar with the Ritchey Pro but anything has to be better than the one that came on mine...

Campag4life

Another tip is...if you want to enlist the eyes here for feedback...there is no substitue for still pics or even video of you on the bike. With modern technology this is easily achieved. Just takes a smart phone or a cheap digital camera with video capability.
How it works is...go into a bike shop that sells Specialized...they will have Roubaixs. Ask for a size 52 test bike. See what kind of ride you can take it on. Let's say its a short ride and you don't know if you like it. It take quite a few miles to acclimate to the road bike position. Initially it will fill too bent over. This quickly changes. Your best bet is this. Tell the shop you want to put the bike on a trainer at the shop and get their opinion on size. Tell them you just want their opinion and nothing more but want to make sure. Hand them the camera and take some pics or video with you in profile on the bike. A picture is worth one thousand words when it comes to fit.
If you don't want your picture on the web and I fully understand this...either crop the pic so it isn't shown...or blur is out with a simple photo editing software. The more feedback you get the better will be your selection.

Sabby

I'm only 5'4". Maybe a half inch taller.

I think Campy has it right...I need to get on a bike and se.

Sabby

To add evidence to this Matt says he's 5'9" and has the 51. It makes me think you're right...that perhaps the sizing is misleading.

Sabby

I'll bring my husband and have him video it. I'm still out of the country so I will try to go this weekend. I get back early Saturday morning.

The bike shop up the street sells only Specialized. I'll ask them if I can test size 52 and a smaller size.

dalava

With a thread like this, who need Retul

Campag4life

The smallest size Roubaix is 49 and next size up is 52 per the chart. Another way to consider fit is where you fit on the bell curve of people. For example at 5'4" with 29-30" inseam...you aren't the shortest person out there. Bike companies make bikes for those that are smaller than you. For the smallest people on the bell curve statistically...that would be the smallest size they make which is the 49. So...you basically are one size up from the smallest riders out there...and that means a 52. Same basic premise applies to the Moto Ti....you wouldn't ride the smallest bike they sell but rather one size up. I for example am on the opposite side of the bell curve but it still applies. I am not the biggest guy out there but at 6'1" I ride one size smaller than the biggest bike out there generally. Most that basically apply what size person they are to generic bike sizes would be just fine without getting overally analytical. If the 52 Roubaix ends up feeling a bit large than spend some time on the 49. But keep in mind when applying this to the Moto Ti that the Moto has a shorter head tube.

A nuance and this maybe an overly technical point but the basis for Rivendell's fit philosophy is...the reason it is easier to size up and not down is...reach is actually shortened with a taller bike....and increase in top tube largely just cancels reduction in reach due to frame height. Reach is comprised of both horizontal and vertical vectors from the handlebar. As the head tube gets longer, the bars raise in the direction of the shoulders by virtue of the head tube angle. This shortens reach and top tube needs to increase in length to compensate. If you want validation of this...study the stack and reach on the Roubaix chart. Roubaixs and many bikes from size to size vary much more in stack aka handlebar height than they do in reach. The reason is the dynamic I explained. Keep in mind that fit is an enigma wrapped in a conundrum. There is no right or wrong only shades of grey and a bit of a moving target as your fitness improves and you improve your speed on the bike which generally results in pursuit of a more aggressive fit.

rpenmanparker 

C4L what you are saying is true, but you are ignoring that different companies make different smallest sizes. Some companies make a 43.5 actual c-t seat tube (about a 47cm traditional size and others start at about 46.5 or 47cm seat tube corresponding to a 50cm traditional size. Motobecane's smallest bike isn't all that small with a seat tube of 48cm. A value company like Motobecane likely just drops off the smallest size and says there isn't enough business there to make it worthwhile to address those customers. If Motobecane's smallest bike is a true (traditional) 51, which it looks to be, that ought to be just right for a 5"4' woman. The next one up would be for me at 5"8'. Sure the top tubes are on the short side, but that isn't so uncommon and probably beneficial for a woman. I just put a 5'4" woman on a Windsor Wellington 47cm frame sized the same way, and it is just about right.

The problem with comparing the Motobecane to a Roubaix is that the sizing charts are denominated differently. Specialized calls its bike sizes according to traditional sizing (seat tube length up to a horizontal top tube) while Motobecane calls its sizes according to the compact seat tube length. So the 52 you recommend in the Specialized bike is really very close to the 48 in the Motobecane with nearly the same seat tube length. And the top tubes are almost identical too. The big difference is in the taller head tube on the Specialized bike vs. the Motobecane. So the smallest Motobecane corresponds to the next to smallest Specialized Roubaix but with a more aggressive geometry common to say crit bikes rather than comfort bikes.

Her test riding experiences will be instructive, no?

Campag4life

I hear what you are saying Robert but what is shown in bold above seems patently false to me. Perhaps you see it different...but the frames are radically different in geometry.

As to the best bike for the OP...she will find it. You may well be right at the end of the day...she may prefer a smaller bike and she stated she would try the smallest Roubaix and one size up...which is the right approach.

I have attached Dave Moulton's fit chart below which comports empirically with thousands of fits he performed as a custom frame maker.
At the end of the day, she may indeed prefer a 49. Dave would have put her on a 50 or so.
Cheers

megalowmatt

But the Motobecane Lechamp is not a true 51 - in fact the effective top tube is what would be considered a medium size in other brands. That's what I wanted to point out with my earlier posts...her CC numbers have her on a bike with a 49-50 ett. The frame she is looking at (the Lechamp) is a 54 ett. It's always difficult ordering online and I wanted to try to point that out to help in the decision.

The Windsor you referenced has what looks like to be a horizontal top tube (there's no geometry chart - just a "sizing tips"), which would make the sizing true to size.

Anyway, I hope this hasn't made it too confusing

rpenmanparker 

Howso false? The actual seat tube lengths are only 0.5 cm different. The top tubes are only 0.2 cm different. Seat tube angles are the same, but the Specialized is one defree shallower than the Moto. The Specialized is more compact and has shorter chainstays. But the really big difference is the head tubes and it is significant. I would say the bikes are for the same size rider but are designed to produce different riding experiences. I think you are saying that compact frames allow us to move among sizes to level out such differences. I just see a downside to taking the larger Motobecane with its longer top tube to get the taller head tube. In any case Jen needs to know the Moto has what for her will be a very aggressive geometry, no matter which of the two sizes she chooses. This is a good exercise.

Sabby

Wow, thanks for all this education! What I will make a point to consider is:

(1) How it feels
(2) If I like size # then I will look at the geometry and use it as a basis for figuring out the Moto's size I need, or any other bike.


(2) is rather nested in (1), so I should right that as 2(1) or 1(2), depending on the parameterization convention you prefer.

Did someone ask if I was good at math? I do math for a living, so I'm passable.

Anyway, I will try the 49 and the 52 for the Roubaix.

So, I'm married to a Cajun. I know how a Cajun would pronounce Roubaix (essentially ROObeh, but Cajuns put the enunciation on different syllables than the French), but how does Specialized pronounce it?

Sabby

Based on my shoe size I need a 52!

The conversation between the two of you is extremely informative to me. The main lesson it teaches me is to not be beholden to the sizing convention of any brand but to figure out a geometry I like and use that as my guide. I won't worry if it's a size 49 or 52, etc, but rather focus on the C-C, C-T, etc, in comparison to how it feels.

I will do my very best to post videos.

How long should a video be? What should I do on the bike (I'll do it on a trainer)? Any specific paces I should go through?

Sabby

I understand what you're saying. And it makes sense, since the tube is sloped.

I had emailed Moto to get the top tube length (because I am an idiot and didn't noticed it on the chart when I looked at it) and the sales guy, Chris, asked for my measurements. So, I sent him the inputs from the compcyclist calculater (not the outputs, just the inputs). He suggested the 48. But who knows if he's just a salesperson or if he's a bike expert, also?

Campag4life

Not only significant but what would be transformative in riding position is the point.
The point if considering either Moto size is...the larger is the less aggressive because of a 20mm taller head tube even with a 5mm longer top tube.
People often comflate a larger bike size with being too stretched out. This is largely nonsense for the reason I explained in an earlier post.
There are many different philosophies when it comes to fit and sometimes there will be little agreement. Sabby will decide what works best through her testing and advice from lbs.

Campag4life

I can tell you are a fast learner. Absolutely. I will say this, I am a huge fan of the Roubaix as I ride one...the Pro model with Campy which they don't sell and I am too fussy to buy off the rack so I built it frameset up with what I like. Yes the Roubaix varies from the two Moto bikes you are considering but you will learn a lot from your comparison if you have a chance to ride both smallest sizes. If you want a closer comparsion with small frame sizes, you could also choose a Tarmac. Or a Tarmac and Roubaix and compare. See if you prefer a taller head tube as many do including me.

As to the video...doesn't have to be long at all. Have the shop adjust your saddle height properly. For the 52, make sure to flip the stem down because of the nice and tall head tube which you may prefer btw.
What you can do is this. Construct a simple chart comparing four bikes....2 smallest Moto Ti's and 2 smallest Roubaixs

Matix should be comprised of:
top tube length
heat tube length
seat tube angle

With this matrix when you ride one or the other Roubaix you will better understand the relationship with the Moto you are considering.

You don't need more than 10-20 seconds of video length...you can perform this on a high level phone or an inexpensive digital camera.

Camera view should be standing to your immediate right side....perpendicular from the bike side...getting the whole bike in the frame. If possible ride with hands on hoods and drops with arms slightly bent and looking forward. Strive to rotate your pelvis and ride with lower back with good posture albeit leaning forward...same posture you stand with...or pick up a heavy object with bent knees...no slumping.

This will be a fun exercise and you will learn a lot in the process.

rpenmanparker 

You're right about both things. I got confused about the Windsor. It was the 50 cm size I built up recently. My daughter wanted one too, but they don't stock the 47 that she needs. She is only one inch shorter than her friend but has a longer torso and needs the smaller frame in this standard geometry model to get top tube clearance. My point was that however it is called, a real 50 or 51 is about right for a 5'4" woman. Thanks for catching the mistake.

Unfortunately there is no help for the need of a very short TT, even in a woman's model. The best hope is that Campag4life is right that the head tube is definitive. The test rides should be quite helpful.

Campag4life

If you do math for a living...I am an engineer btw....than what has been written will make perfect sense to you.
The point is fit is pretty nuanced and often contested here. It turns out to be a bit of personal decision honed from trying many different fits to determine what works best.
As to pronouncing Roubaix...its pronounced RO-bay....O is long...accent on first syllable.

rpenmanparker 

Roubaix is a town in France that is the end of a most grueling spring classics race that starts in Paris and travels over the worst roads imaginable, much of them cobblestones and usually wet and muddy at this time of year. Naming a bike this suggests it would be comfortable for long days in the saddle over less than pristine roads. Near as I can tell, in France the town name is pronounced with more emphasis on the first syllable, but not much more. From what I have heard, so is the bike.

BTW I'm a native New Orleanean, myself, so I know exactly what you mean.

rpenmanparker 

C4L, Jen something just occurred to me. Riding the Roubaix is a fine idea. Beyond that Jen wants titanium and the Motobecane is affordable for her pretty much eliminating other choices, providing one of the Motos would be a good fit. This If she has her heart set on the Moto, shouldn't she test ride a bike very much like it to determine if it will work for her. Wouldn't comparing the two similar sizes of a similar bike be the way to know which Moto to buy (assuming one will be okay). I was just wondering if we wouldn't be more helpful by finding her a close match in a common brand (Specialized, Giant, Trek) that would help her assess the pros and cons of those short head tubes on the Moto. The 52 cm Specialized Tarmac is very much like the 48 Moto except 1 cm taller head tube. That's pretty close. I will look for others.

Jen, I apologize for talking about you in the third person when you are figuratively standing right here (if you know what I mean). It is hard to know what is the right forum ethics in this case when responding to one person's post about another person.

Robert

Campag4life

What you write makes sense. Why I suggested the Tarmac in a previous post as well. Depends how micro Jen wants to get. At this point she doesn't know if she would like more a racing geometry like the Moto or a comfort geometry like the Roubaix. Her perception about the Moto may change for example after riding the Roubaix. Or...by slamming the stem...she can do this also on the 49 Roubaix as well to replicate the Moto position. Reality is...when starting fresh, somebody new to riding a road bike...or revisiting after many years will not know what is best. Further she could really ride all bikes discussed in different sizes. One size or type...racing versus comfort may be best for her. I am of the mind that one really can't hone or distill fit until about the 4th road bike...my opinion. Basically we all learn by our mistakes and experimenting away from the margin we believe is a good starting point. I have experimented with fit after my 50th road bike. The holy grail is elusive and there is no substitute for experience.

Sabby

Hey, guy, I apologize for the lack of response. The last two work days have been very intense. Working until 8-9pm and then going home and staying up long enough to shower and call the family back home. And today I head back home. I have two flights ahead of me, one of them nearly 17 hours. So, I will definitely be away from this thread for the next few days.

That being said, I can't believe how awesome you two are. And I appreciate Matt's personal experience. I can't thank you guys enough.


So, I will do what Campy said re the video and I made the matrix, including Roubaix, Moto, and Tarmac. The Moto definitely has a shorter HT length than the Roubaix. Overall it seems the Moto is in between the Roubaix and the Tarmac.


[TABLE]
[TR]
[TD]Brand[/TD]
[TD="colspan: 2"]Roubaix[/TD]
[TD="colspan: 2"]Moto[/TD]
[TD="colspan: 2"]Tarmac[/TD]
[/TR]
[TR]
[TD]Size[/TD]
[TD]49[/TD]
[TD]52[/TD]
[TD]48[/TD]
[TD]51[/TD]
[TD]49[/TD]
[TD]52[/TD]
[/TR]
[TR]
[TD]Measurements[/TD]
[/TR]
[TR]
[TD]Top Tube Length[/TD]
[TD]518[/TD]
[TD="bgcolor: #FFFF00"]537[/TD]
[TD="bgcolor: #FFFF00"]535[/TD]
[TD]540[/TD]
[TD]518[/TD]
[TD="bgcolor: #FFFF00"]537[/TD]
[/TR]
[TR]
[TD]Head Tube Length[/TD]
[TD="bgcolor: #FF3333"]125[/TD]
[TD]145[/TD]
[TD="bgcolor: #00FF00"]110[/TD]
[TD="bgcolor: #FF3333"]130[/TD]
[TD="bgcolor: #00FF00"]100[/TD]
[TD]120[/TD]
[/TR]
[TR]
[TD]Seat Tube Angle[/TD]
[TD]75.5[/TD]
[TD="bgcolor: #E6E64C"]74[/TD]
[TD="bgcolor: #E6E64C"]74[/TD]
[TD="bgcolor: #E6E64C"]74[/TD]
[TD]75.5[/TD]
[TD="bgcolor: #E6E64C"]74[/TD]
[/TR]
[/TABLE]