* A long and boring look into the numbers of geometry

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• 11-12-08, 10:48 PM
SaiKaiTai
* A long and boring look into the numbers of geometry
As I dig into the numbers to define my new "steelie" I think I begin to see.

Right now, the standards I have are my LeMond and my Giant.
They're the only bikes I have -or have had- any meaningful hours with.
So, I think of what characteristics I like in each or both of them and I look at the numbers.

Ah, the numbers.
Based on some of the answers I got from y'all and articles I've found in my online research, I put together some numbers that I'd guess had something to do with anything. I used numbers from my bikes, some that I'm interested in, and one mythical standard of the Retro Ideal.

Warning, I probably have ZERO idea what I'm talking about

Materials, and the obvious, aside -the LeMond is aluminium. the Giant is pure carbon- here's what I have:

I like the quick handling and snappy -almost twitchy- responsiveness of the LeMond and the comfort and stability of the Giant. Not that the Giant isn't responsive, it is but it doesn't have that snap.
Even so, the LeMond oddly feels like it has more inertia to overcome when you start off but still responds as quickly but more slowly than the Giant.
I know that doesn't make any sense but that's the only way I can describe it.
Anyway, I ascribe that more to the longer cranks and bigger rings than the Giant.
More torque bur slow developing.
The LeMond is definitely a more jarring ride. The Giant feels rock steady in the downhill twisties at least up to the speeds I'm willing to go which, to date, is 45+ mph. The bike does not waver.

So, what do the numbers say?

The LeMond has a shorter wheelbase and chainstays.
The headtube angle is a full degree more upright on the LeMond (73.5 vs. 72.5)
The front of the LeMond is a bit shorter on the LeMond.
Both have the same BB height but the LeMond has a shorter drop. This might be a measurement error on my part.

So, now I have to figure out what kind of bike I want but the Smoothie looks like a steel Reno while the Smoothie ES looks more like a steel Giant with a longer wheelbase and chainstays. The Smoothie ES with a B-67 and some 32mm tires sounds like an all day sucker for your love. Hm. Will 32s fit? 28s will do fine.
• 11-12-08, 11:46 PM
BluesDawg
B-67? I'm not seeing the Smoothie ES as an upright bike calling for a wide, sprung saddle. It will take 32mm tires with fenders.
• 11-13-08, 07:17 AM
BikeWNC
You have to decide what this bike is going to be. I wouldn't consider a bike with 32c tires to be snappy. Do you want a race bike or a cruiser?
• 11-13-08, 08:37 AM
The Smokester
SKT,
Last year I probably shopped at some of the same stores you are now. I considered the Soma Smoothie but ultimately bought the Gunnar Sport. My purpose was ultra long distance but now the Gunnar bike is pretty much my "go to" bike. It is amazing how comfortable and smooth this bike is with 28mm tires and 36 spoke wheels, yet it steers more precisely and responsively then any other bike I have had. So, geometry really makes a difference.
• 11-13-08, 08:47 AM
SaiKaiTai
Quote:

Originally Posted by ddac
What size is your LeMond? Mine has a 72.5 Head angle. But I have a smaller frame.

Mine is a 55cm

Quote:

Originally Posted by BikeWNC
You have to decide what this bike is going to be. I wouldn't consider a bike with 32c tires to be snappy. Do you want a race bike or a cruiser?

Agreed about the responsiveness of the 32mm tires but I think I've already answered the question. Kind of.
• 11-13-08, 08:55 AM
BikeWNC
Quote:

Originally Posted by The Smokester
SKT,
Last year I probably shopped at some of the same stores you are now. I considered the Soma Smoothie but ultimately bought the Gunnar Sport. My purpose was ultra long distance but now the Gunnar bike is pretty much my "go to" bike. It is amazing how comfortable and smooth this bike is with 28mm tires and 36 spoke wheels, yet it steers more precisely and responsively then any other bike I have had. So, geometry really makes a difference.

A Gunnar Sport is a great bike. Perhaps not the lightest frame out there but for all day rides it's very nice. I'd like to get one and build it as a brevet bike. I think the Gunnar uses a better tubeset than the Soma, if my memory is correct.
• 11-13-08, 09:11 AM
cyclezen
Quote:

Originally Posted by SaiKaiTai
So, I think of what characteristics I like in each or both of them and I look at the numbers.

Ah, the numbers.
...
Materials, and the obvious, aside -the LeMond is aluminium. the Giant is pure carbon- here's what I have:

I like the quick handling and snappy -almost twitchy- responsiveness of the LeMond and the comfort and stability of the Giant. Not that the Giant isn't responsive, it is but it doesn't have that snap.
Even so, the LeMond oddly feels like it has more inertia to overcome when you start off but still responds as quickly but more slowly than the Giant.
I know that doesn't make any sense but that's the only way I can describe it.
Anyway, I ascribe that more to the longer cranks and bigger rings than the Giant.
More torque bur slow developing.
The LeMond is definitely a more jarring ride. The Giant feels rock steady in the downhill twisties at least up to the speeds I'm willing to go which, to date, is 45+ mph. The bike does not waver.
...

So, now I have to figure out what kind of bike I want but the Smoothie looks like a steel Reno while the Smoothie ES looks more like a steel Giant with a longer wheelbase and chainstays. The Smoothie ES with a B-67 and some 32mm tires sounds like an all day sucker for your love. Hm. Will 32s fit? 28s will do fine.

getting this out of the way... bike size has a bit to do with numbers, and you don;t mention the sizes of your current bikes...
but numbers is just numbers
ultimately you can;t divorce the material from the comparo, its THAT important.
3 bikes with Identical numbers in the 4 diff. (&TI) materials (wish I could try/include bamboo!) are gonna ride very differently for each of us.
..."quick handling and snappy -almost twitchy- responsiveness of the LeMond and the comfort and stability of the Giant"... is most certainly attributable to the materials as much as anything else.
and then its down to wheels...
If you don;t want to have just another bike with a nuance of differences - sortta like differences in Dreadnaught axes, then maybe go more different...
I bike that fits 32s is certainly different, as long as its not too 'quirky' in other areas. Then having 2 sets of wheels for it (which can be used on any of the other 700c bikes - assuming they follow Shimano or Campy stds) will give 2 very different personalities.
I will note that 'light' wheels don;t necessarily make them tender... Nor does high spoke count guarantee a bomb-proof wheel. The rims are important.
Inherently, the 'liveliness' of a nicely designed and brazed steel combined with solid' 'stuff' will make it a 'got-to' bike for a variety of uses.
IMO
• 11-13-08, 10:04 AM
Hermes
Quote:

Originally Posted by cyclezen
getting this out of the way... bike size has a bit to do with numbers, and you don;t mention the sizes of your current bikes...
but numbers is just numbers
ultimately you can;t divorce the material from the comparo, its THAT important.
3 bikes with Identical numbers in the 4 diff. (&TI) materials (wish I could try/include bamboo!) are gonna ride very differently for each of us.
..."quick handling and snappy -almost twitchy- responsiveness of the LeMond and the comfort and stability of the Giant"... is most certainly attributable to the materials as much as anything else.
and then its down to wheels...
If you don;t want to have just another bike with a nuance of differences - sortta like differences in Dreadnaught axes, then maybe go more different...
I bike that fits 32s is certainly different, as long as its not too 'quirky' in other areas. Then having 2 sets of wheels for it (which can be used on any of the other 700c bikes - assuming they follow Shimano or Campy stds) will give 2 very different personalities.
I will note that 'light' wheels don;t necessarily make them tender... Nor does high spoke count guarantee a bomb-proof wheel. The rims are important.
Inherently, the 'liveliness' of a nicely designed and brazed steel combined with solid' 'stuff' will make it a 'got-to' bike for a variety of uses.
IMO

+1 One has to consider the material and what a manufacturer can do with it. Steel frame sets are made with round steel tubes. To make the tubes lighter, they are thinned in the middle. One could imagine that the frame set could consist of thinned and un-thinned tubes to change the weight and the ride. IMHO, geometry is important for steel because it will determine the type of ride and the thinning of the tubes and quality of the steel or alloy the weight. Cheaper frames will consist of similar or identical tubes that are heavier.

Carbon fiber changes the equation. It is lighter and can be use creatively to change the shape of the tubes for improved aerodynamics and tweak the ride. My Cervelo R3 is a prime example. The seat stays are ridiculously thin but the design is such that they are not required for strength. All the strength is in the bottom bracket, chain stays and squoval down tube. These shapes and their performance are not possible with steel at the weight. The seat stays are used to hold the rear brake and act like springs. Hence the ride of the R3 is smooth over rough road even though it is a short wheel base frame with short chain stays and it is very light. I suspect it would be impossible to design the R3 out of steel.

On the other hand, Serotta uses Niobium steel alloy made by Columbus, a carbon fork and carbon stays in their classic steel design to get low weight and a plush ride.

And wheelsets can make a significant difference in the ride and as noted above and it is not obvious by looking at them and counting spokes with either less or more spokes being better or worse. For me, there is no way that I would run anything but 23 mm tires UNLESS it was off road. With our terrain, larger tires are pure overhead that is ridiculous to carry around. One interesting point on the Cervelo R3 is that is will accommodate 25 mm tires since it was conceived and designed for the torture of Paris Roubaix.:thumb:

Happy hunting.:)
• 11-13-08, 10:18 AM
SaiKaiTai
I think I'm about ready to give up on the idea at this point.
• 11-13-08, 11:22 AM
BluesDawg
Reviewing the geometry numbers can give you a good indication of how a bike might ride and handle. But there are so many other variables at work, some mentioned above and many others, that only extended riding can tell you for sure how that bike will work and feel.

BTW, a friend of mine just built up a Soma Smoothie ES for his girlfriend and she loves it.
• 11-13-08, 11:51 AM
SaiKaiTai
Yeah, the proof of the pudding and all that....
It just gets a little complicated when you can't try it out first
• 11-13-08, 01:32 PM
stapfam
Quote:

Originally Posted by SaiKaiTai
I think I'm about ready to give up on the idea at this point.

Wouldn't give up yet- but There are such a variety of bikes out there- I would hold on for a bit. Winter is coming on and time to get out and arrange test rides for as many types of bike as possible. Don't just mean manufacturers either- Get a test on a Performance frame- or even one of the top racing frames. And do not just go for steel- Retry the Giants in the TCR range- Or even the Alliance- that is one frame I wished I had tested before I got the TCR. Still think the TCR would have won for me though.

No rush to get another bike- or is there?
• 11-13-08, 02:15 PM
Hermes
Quote:

Originally Posted by ddac
Many of you here seem to have pretty good knowledge of frame geometry and how it affects the characteristics/personality of the bike. I started a thread asking geometry gurus for help in selecting the most relaxed bike of the bunch. But it seems like I'm not able to get any concrete answers.

For those of you who would like a challenge, here were the bikes I looked at. From a quick look at the geometry, would you be able to tell which bike(s) have the most relaxed geometry?

These are all track / single speed and cheap. BTW...nothing wrong with cheap or BDs mark it up mark it down marketing strategy. I suggest you take the one with the longest wheelbase. I suspect it will offer the best ride. A long wheelbase car rides smoother than a shorter one. The wheelsets provided at that price point are going to me marginal but hey you are going to get exactly what you pay for. For example, an okay set of track wheels on Ebay is \$250 to 300.

I ride / race at the track and track bikes in general have high ground clearance and a shorter wheelbase so they are NOT great for plush rides over long distances. They are designed to manage high speed turns on a bank with high power out of the saddle pedaling. I suspect this is why no one can offer any advice about which offers a more relaxed ride.
• 11-13-08, 02:25 PM
Oh dear, here I go again:lol:
As I said in a reply to your other thread when you first mooted the idea, leaving aside 'N+1' or pure, simple, bike-lust (not that there's anything wrong with either of those!): what, precisely, is 'new bike' going to do (assuming it's another road bike) that your current two don't? A steel sport road/sport touring bike is NOT going to have the 'snap' of your Giant or Lemond; do you want more of that? To get it, you need a full-on race bike, running 23 or 25 tires.
Your Giant, certainly, will take 28s (it has the clearances/deep-drop brakes necessary). If you run a bike with 32s, chances are you're giving up even more 'snap'. What's the gain? Are you after more 'all day' comfort?? That might make sense, but even then a full-carbon OCR with 28s on really good wheels is purty comfy. Or do you want to do some light (i.e. more that 'credit card', carrying at least some kind of luggage) touring? If so, then I do see the addition making sense, but otherwise ...??
Just sayin!:)
• 11-13-08, 02:43 PM
SaiKaiTai
I think we're dealing with lust, no question :lol:
But, as I've stated somewhere in all of this, I want the bike my Kaitai should have been.
More road oriented but rugged, comfortable and still able to handle a dirt or gravel path.
It doesn't have to be as snappy as my Reno but I don't want a "pig" either
• 11-13-08, 02:54 PM
Hermes
Quote:

Originally Posted by SaiKaiTai
I think we're dealing with lust, no question :lol:
But, as I've stated somewhere in all of this, I want the bike my Kaitai should have been.
More road oriented but rugged, comfortable and still able to handle a dirt or gravel path.
It doesn't have to be as snappy as my Reno but I don't want a "pig" either

Dah...cycle cross. Check this out. http://www.feltracing.com/08/product...,1513&pid=8719

I am taking two of these and going back to work.

http://i170.photobucket.com/albums/u...Fredcedrin.jpg
• 11-13-08, 03:00 PM
BluesDawg
Quote:

Originally Posted by SaiKaiTai
I think we're dealing with lust, no question :lol:
But, as I've stated somewhere in all of this, I want the bike my Kaitai should have been.
More road oriented but rugged, comfortable and still able to handle a dirt or gravel path.
It doesn't have to be as snappy as my Reno but I don't want a "pig" either

Salsa La Cruz
http://www.salsacycles.com/images/zoom_laCruzComp08.jpg
• 11-13-08, 03:58 PM
SaiKaiTai
Gee... the specs aren't really all that different from the Jamis you said I didn't want
Except, the Jamis comes with a triple and lower gears in the back - just like I want.
• 11-13-08, 06:54 PM
Quote:

Originally Posted by SaiKaiTai
I think we're dealing with lust, no question :lol:
But, as I've stated somewhere in all of this, I want the bike my Kaitai should have been.
More road oriented but rugged, comfortable and still able to handle a dirt or gravel path.
It doesn't have to be as snappy as my Reno but I don't want a "pig" either

Good oh -- now I get it/must have missed that step somewhere:o
As a couple others say right above, really does sound like you're wantin' a 'cross bike -- assuming you're not talking full-on mtb'ing, but rather just the ability to ride what the Brits call 'rough stuff'. Lots of choice these days, I would have thought. Are you wedded to drop-bars, or would you (re)consider flats w/bar ends? That would open up the choice even more; e.g. you have a Giant, take a look at the FCRAlliance: canti brakes, clearance for up to about 35/38 tires, amazing 'comfort', wide-range gearing, etc. I just mention this one example because I'm seriously considering one to replace my 'roadified' mtb; it'll do everything I want (commute, tire switch, long rides, light touring, etc.), and have test ridden it extensively, on both unpaved and paved surfaces: very "road oriented but rugged ..." as you say above. But that's just me; I like flats w/bar ends, others don't.
• 11-13-08, 07:06 PM
SaiKaiTai
Quote:

Good oh -- now I get it/must have missed that step somewhere:o
As a couple others say right above, really does sound like you're wantin' a 'cross bike -- assuming you're not talking full-on mtb'ing, but rather just the ability to ride what the Brits call 'rough stuff'. Lots of choice these days, I would have thought. Are you wedded to drop-bars, or would you (re)consider flats w/bar ends? That would open up the choice even more; e.g. you have a Giant, take a look at the FCRAlliance: canti brakes, clearance for up to about 35/38 tires, amazing 'comfort', wide-range gearing, etc. I just mention this one example because I'm seriously considering one to replace my 'roadified' mtb; it'll do everything I want (commute, tire switch, long rides, light touring, etc.), and have test ridden it extensively, on both unpaved and paved surfaces: very "road oriented but rugged ..." as you say above. But that's just me; I like flats w/bar ends, others don't.

Good points, here. And I do know about the Giant FCR, Mrs S has one (which is how I ended up with my OCR). I'm very, very impressed with that bike and Giant in general. So, yeah, a lighter, more responsive flat bar? Hmm... that's a thought. Bars would do nice job of "being hoods" but do have a bias toward road set ups. As for the CX idea, no... won't work. Have to say it was first thing I thought of. It seemed perfect but, for me, there aren't enough rings up front and the back doesn't go low enough. yeah, I could change it but why? And again, that seems to kind of lead me back to the Jamis. I really need to ride it again in more depth.
• 11-13-08, 07:09 PM
Wildwood
Your whole dilemma of geometry, tubes, capabilities, feel, etc could all be worked out by a good framebuilder. Show him what you've got, tell him what you want and \$1,200 - \$1,600 later you should have your dream frame. Lugged or TIGed, the braze-ons you want, in the color of your desires. What the heck, get a stem painted to match. And make mine Campy.

Just do it.
• 11-13-08, 09:07 PM
BengeBoy
Quote:

Originally Posted by SaiKaiTai
As for the CX idea, no... won't work. Have to say it was first thing I thought of. It seemed perfect but, for me, there aren't enough rings up front and the back doesn't go low enough. yeah, I could change it but why?

Are you saying you don't want a 'cross bike because the gearing isn't low enough? Check out a Bianchi Volpe (steel, triple chainring). Or just build up a Soma Double Cross with a triple. Or a Surly Crosscheck with a triple. Or a Gunnar with a triple.

Also, if God didn't want you to change gearing, he wouldn't have invented chainwhips.
• 11-14-08, 02:17 AM
BluesDawg
Quote:

Originally Posted by SaiKaiTai
Gee... the specs aren't really all that different from the Jamis you said I didn't want
Except, the Jamis comes with a triple and lower gears in the back - just like I want.

I never said that about the Jamis. I like the Jamis. All I said was that it looked like a cyclocross frame more than a touring frame. And it does. The La Cruz is also a cyclocross bike. From what you say you want from this bike, I think a cyclocross bike would be a good choice. That is why I threw another one out there for consideration. (BTW, the Salsa also comes as a frameset, so you could build up anyway you like). A cyclocross frame with a triple crank and set up as a tourer (like the Jamis) might be a very good choice.
• 11-14-08, 06:17 AM
Quote:

Originally Posted by BluesDawg
I never said that about the Jamis. I like the Jamis. All I said was that it looked like a cyclocross frame more than a touring frame. And it does. The La Cruz is also a cyclocross bike. From what you say you want from this bike, I think a cyclocross bike would be a good choice. That is why I threw another one out there for consideration. (BTW, the Salsa also comes as a frameset, so you could build up anyway you like). A cyclocross frame with a triple crank and set up as a tourer (like the Jamis) might be a very good choice.

++1: right now, with the popularity of 'cross both as a race discipline and, consequently, a popular 'bike type', there are many bikes based off 'cross which are not really full-on race bikes (which is what you [S.] don't want), but actually more like on/light off-road sport touring bikes. Something like the Salsa as per BluesD. really might be just the ticket.
• 11-18-08, 10:44 AM
The Smokester
Quote:

Originally Posted by BikeWNC
A Gunnar Sport is a great bike. Perhaps not the lightest frame out there but for all day rides it's very nice. I'd like to get one and build it as a brevet bike. I think the Gunnar uses a better tubeset than the Soma, if my memory is correct.

That's basically my purpose...Long distance. So far I have done 140 miles in a single day on it. Very comfortable. Without fenders and with a heavy (but comfortable) Selle An-Atomica saddle it comes in at about 20 pounds (mine also has S&S couplers). I have a 12-34 rear cluster on it and a 48/36/26 treking crank so it will go up anything. Even on Centuries where the route planners just love to throw a 12%+ 5-mile-long grade at you right at the end it makes things pretty easy.
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