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new comments? "compact vs. traditional geom"(24 posts)

new comments? "compact vs. traditional geom"bm
Aug 13, 2002 10:01 PM
searching net articles, i found a distinct advantage of compact frames is stiffness . . . but stiffness is only apparent in out of saddle climbing (because of a lower center of gravity) . . . while seated, there isn't much difference.

any personal experiences or comments regarding compact frames?

AND, if you were to purchase a compact or traditional bike what would you choose? (considering lower COG, $$, stiffness, weight, etc)
re: new comments? "compact vs. traditional geom"Rich_Racer
Aug 14, 2002 1:41 AM
Extra Stiffness is not necerssarily a good thing. A bike can be too stiff. There's a trade off between comfort and efficiency where stiffness is concerned that relates to the material, geometry, size of tubes, etc, etc. Bike manufacturers have spent years researching this in terms of traditional frames but compact frames are perhaps still in the early stages of development.

Rich.
i thought they were designed for skirt wearing men ;-) NmSpirito
Aug 14, 2002 4:11 AM
Is there a problem with guys wearing skirts? nmJuanmoretime
Aug 14, 2002 4:41 AM
Not for some guys evidently! www.utilikilts.com NMslide
Aug 14, 2002 4:44 AM
www.utilikilts.com
Got both, andEager Beagle
Aug 14, 2002 5:33 AM
can't tell the diffrence in stiffness. Both 7000 Al in a 56cc (equal). I think it's just a style thing. Wheel build/stiffness will make far more difference.

The CoG issue is a red herring - lowering that TT by a tad makes no noticeable difference (esp is you have a yard of cheap heavier seat post instead).

I'd just get the best components/wheels/quality frame package that you can find, and ignore the compact/trad issue entirely, unless you have strong feelings about the look.
Sloping vs. Traditionaljjohnson05
Aug 14, 2002 6:06 AM
If you go to www.orbea-usa.com and compare the geometry charts for traditional and sloping (voop) frames you will se that the only difference is the point at which the top tube intersects the seat tube. All of the virtual measurements are the same. That being the case, the Orbeas should give identical rides whether sloping or not.
personal opinionweiwentg
Aug 14, 2002 6:38 AM
not only am I short, but I have relatively short legs. I can fit on most small compacts, but I can't fit on a lot of standard frames (unless we're talking 47cm; a lot of 48s and most 49s are out).
personal opinioncapnjim01
Aug 14, 2002 7:34 AM
I don't have as much problem as you seem too. Fit kit says I need a 48cm seat tube and 53cm top tube. Not a lot of frames in that size. I have been riding a 54 (didn't know any better LBS had one on sale said it was my size.) I only have about 2 inches of seat post showing, so am i better off with smaller frame and more seat post or going for size using the top tube as ,my guide. I have longer torso realitive to leg length.
lucky youweiwentg
Aug 15, 2002 12:44 AM
I've not used a fit kit yet. but I estimate that I need a 53cm TT, and something like a 47 seat tube or less. there are some 14" MTBs on which I don't have enough standover clearance (Santa Cruzes, for example)
don't like the aestheticsDougSloan
Aug 14, 2002 6:44 AM
While they may be useful for short riders needing more standover clearance, I don't like them. I prefer the look of the level top tube, maybe simply for traditionalist reasons.

The small seat tube means less room for water bottle and a much longer seat post. Much of the weight advantage is lost with the longer post.

I think the sloping TT is nothing but marketing or bean-counter efforts, simply trying to be different or building fewer frame sizes for some companies.

Just my opinion, but then again, I could be wrong.

Doug
marketing to mtb'ers maybe?TomS
Aug 14, 2002 7:17 AM
Even though mtn bikes come in many sizes instead of the S/M/L that most compact road bikes have, the compact road frame looks a bit like a hardtail mtn bike frame. So maybe it looks more "familiar" to someone coming over from mtn bikes. I think they look pretty cool, and it might be because I grew up riding bmx and mtn bikes, so that's the look I'm used to (small frame, long seat post).

Just a thought. *shrug*
re: new comments? "compact vs. traditional geom"legs
Aug 14, 2002 7:25 AM
I will never ride a standard frame again. Before I had ever ridden a compact i felt the same way most of these posters feel about them.. and in my experience people that hate them have never really spent time on one.
The experience in the saddle is virtually identical to a standard frame.. but the bike does something special when you stand-up... Tom Kellog writes about this on the Spectrum site and after about three months of 200 mile weeks in an Xll Compact.. I have the same sensations and I will never go back.

There is also a perception of a lower center of gravity on the bike that affects descending...the closest metaphor I can come up with is that it feels like you are on your belly right above the ground versus standing up on a skateboard... it is th e best descending bike i have ever ridden.

I think you owe yourself few test rides I dont think its a fad. And as fas as making a bike stiffer.. it just depends.. I do think a sloping TT is a perfect application for a titanium bike... the smaller main triangle eliminates the 'softness' of titanium IMO.

The last pro race I saw.. the field was over 60% compact frames... (at the Manhattan Beach GP)....
so appearently I am not the only one...

Like I said.. I cant see myself on anything but a sloping TT frame anymore... and I hated the idea of them until I spent a weekend test riding one.

So I suppose the only way for you to find out is to answer for yourself. Just like traditional designed frames.. one compact is not a representaion of the ride of all others...

I wouldnt make a decision on what I like based on a bunch of strangers opinions.. who knows how many of these guys aren't total wannabes ..
and you can even find varying opinions at different bike stores..

you gotta find out for yourself... I think it is worth a few test rides..
I suggest the Merlin Xl Compact, the Merckx Teams Sc with a sloping TT, the Principia, a Schwinn Fastback (if you can find one), and a Derosa King. These bikes are all available compact.. they are at varying price points (the schwinn is three hundred bucks) and they are all different feeling great bikes.... Try and ride these models and you will have left nothing to doubt..
I've got both, race and ride bothNo_sprint
Aug 14, 2002 7:28 AM
My semi sloping is definitely lighter and stiffer, then again, it's a QPro...

It's a toss up. I don't think either offers any great advantage.
re: new comments? "compact vs. traditional geom"clintb
Aug 14, 2002 7:43 AM
I have both, an 01 Giant TCR Zero and a 93 C-Dale 2.8 framed R900 (Ultegra). After much research, comparison and measurements the Giant had the overall geometry I was looking for. Oh, the Giant is a Large and the Dale is a 60cm. Oddly enough, the TCR has a 58.5cm top tube and the Dale is shorter, although I can't remember by how much.

I had the itch for a new bike and just happened to get a great deal on the TCR. Only 2K fully Dura-Ace equipped. So far I really like it. The ride is noticeably smoother than the super stiff C-Dale and it's a whole lot lighter.

Some of it does come down to personal preferences though. The look of a compact turns off some people, but I like it. I'm however, not buying the argument about the longer seatpost that Doug mentioned, and I've seen elsewhere many times. My large frame is 1105 grams, and the USE 27.2x350 carbon post I have is 174 grams. You don't have to have a giagantic water pipe to get the job done, just a careful selection of parts. I also didn't go for a compact because of any weight savings. I just happened to get a killer deal on a complete bike that worked for me.

Go test ride and forget about "Compact vs. Traditional". Your body will tell you what's right.
do you buy Doug's less-room-for-water-bottle argument?ET
Aug 14, 2002 10:36 AM
There's must be SOME reason an ugly compact is inferior. Anything at all you can find. PLEASE!!!
long postsyeah right
Aug 14, 2002 10:54 AM
that USE carbon post is exactly what scares my large butt when I think about compact frames. double the length of exposed seatpost, especially with a little set back, and you've got some serious moments placed on the post any time you hit a bump or anything. I'd be freaked out to use a light post, because breaking one would absolutely suck.
long postsclintb
Aug 19, 2002 8:02 PM
ET,

My TCR is a large, so it'll be a bit different from the small. I have no problem with using a 24oz Polar bottle in the seat tube mounted cage. It's not even a really tight fit. Now that may be a bit different on a small, but I've seen someone with the small post that it wasn't a problem for them.

yeah right,
I'm not using the entire length of the 350 USE carbon. If memory serves, only about 165-170mm of carbon is exposed. Call me safety conscience. Also, I wanted something long enough that if I swap it to a MTB, then length wouldn't be an issue. We're only talking 174g for a 350mm post, so I wanted more options.
Warning to all that may be considering a compactpinarello
Aug 14, 2002 8:58 AM
I just bought two new DeRosa's. One is a King and the other a Merak. The King is a 46.5 and the Merak is a 48. The King does not have enough room to accomodate a second bottle. The Merak does. If you are ordering a bike frame this may be a consideration when deciding size. Catapult
superior stiffness of compactsET
Aug 14, 2002 10:41 AM
It may be true, but I've never understood this. I mean, slant the top tube a bit more and you have an old-fashioned lady's bike serious cyclists avoid, because it lacks stiffness.
isn't it becauseTomS
Aug 14, 2002 11:07 AM
The seat tube is shorter, so there is less room for the bottom bracket to "swing"; assuming most frame flex (while sprinting anyway) is because the bottom bracket is essentially swinging side to side, with the seat tube and down tube holding it up. Or am I way off base here?

On the "lady's" bikes, the top tube is almost like a second downtube, they both attach to the seat tube near the bottom; it seems like that would create a second direction of flex, where there is nothing stopping the seat tube from moving front-to-back, not just side-to-side. Of course I don't think many bikes this style were designed to eliminate flex, or made of super-stiff materials either!
re: new comments? "compact vs. traditional geom"aliensporebomb
Aug 14, 2002 12:51 PM
I'm the owner of a Giant TCR2 and notice several things:

(1) before I got my roadie this year I'd switched from road to mountain almost exclusively for four years. This familiarity with
mountain geometry and sizing may have predisposed me to like the
compact frame designs so caveat emptor.

(2) the compact frame fit me better due to my bizzarre body type (tall torso, short legs) and felt more "at home" possibly since it seemed similar to my 16" mountain frame.

(3) climbing out of the saddle seemed to work better. I'm not sure why but it just felt more "secure"..

(4) descending seemed to work a little nicer too since I felt "closer to the ground" (which could be daunting for some other people).

(5) it also feels like my center of gravity is closer to the ground, i.e. less of a chance of me falling over clipped in or something stupid like that.

I like it. it's fast, it's cool.
A few differences...RCole
Aug 14, 2002 7:12 PM
I recently replaced my LS Vortex with a Merlin XL Compact. I rode a 57 in the LS and a Large in the Merlin. The Merlin has a bit more flex but is plenty stiff. I notice the CoG difference on the Merlin, as it corners much better than the Vortex. I had to take wider angle turns with the LS but can cut a close corner with the compact. Also, for whatever reason, the Merlin is a bit faster on the downhill. I ride the same loop a couple times a week and can definately tell the difference. I'm no engineer and can't explain the why's and hows but there you go.
aesthetics mainly....little sloping is ok, too much is ugly (nm)Raf1
Aug 14, 2002 11:59 PM