Road Cycling - compact vs. tradtional geometry

what are the real world advantages\disadvantages of having compact geometry vs. tradtional? i've never really understood this too well.

what are the real world advantages\disadvantages of having compact geometry vs. tradtional? i've never really understood this too well.

From a manufacturer's view point, a compact frame provides the opportunity to reduce the total number of sizes the frame is produced in (a la Giant). However, some manufacturers still make a variety of compact sizes.

From a rider's perspective, a compact frame can be stiffer and can potentially provide a weight reduction. On the downside (and I'm surprised I haven't seen it mentioned here before), smaller compact frames make it difficult to remove a water bottle from the seat tube mount.

Other than that, it's all personal preference.

-mark

It's been discussed extensively on this forum. Perform a search the road cycling section using the words "sloping" or "compact", and you'll soon find the relevent threads. Here's a very good thread from last August:
http://www.bikeforums.net/showthread.php?t=26661&highlight=bankrupt , and a similar one from last December: http://www.bikeforums.net/showthread.php?t=42587&highlight=compact

Cannondale's opinion is very interesting:
http://www.cannondale.com/bikes/innovation/sloping.html , and here's what Cervelo say about it:

"The differences between sloping and horizontal are small, especially when compared to things like tubeshapes and butting options. But if you use the same tubeset for both frames, the following differences will occur:

Slightly higher bottom bracker stiffness for the sloping frame
Slightly higher torsional stiffness for the horizontal toptube frame
Slightly lighter frame with the sloping toptube
Slightly lighter seatpost wit the horizontal toptube frame
Slightly more seatpost compliance with the sloping frame.

Issues 3 and 4 are a wash, and for us at Cervèlo the choice between sloping and horizontal depends on what combination we are looking for out of 1, 2 and 5. For our Alu bikes, which have plenty of bb and torsional stiffness anyway, we go with a sloping toptube (or a dropped toptube on the tri bikes which has the same effect) to get a bit more seatpost compliance.

For the steel frames, this is not necessary and so we can increase the torsional stiffness by keeping the toptube horizontal, especially nice for the twisting and turning on rough roads.

For the new carbon frame, the seatpost compliance wasn't an issue but we did want to get the highest possible bb stiffness, so we opted for a sloping frame.

531 ...

that's an interesting perpective from cannondale. i recently bought a new road bike, and owning a cannodale mtn bike i wanted a cdale road bike as well. i rode various sizes of the R600 and could not get it to fit. i test rode a number of other bikes as well and ended up with a lemond tourmalet with the compact geometry. the tourmalet just plain fit my body better. so, if the bike fits ride it, compact or traditional geometry.

-- michael

I recently bought and have ridden a significant amount(260kms) since my pruchase a week ago and here's what I observed.

CrMo traditional frame:
size: 50cm
ST: 49cm (C-C)
TT: 53.5 C-C
fork: LOOK HSC3 Carbon fork
weight(bike): 19lbs (8.63kg)
components: shimano 105/ultegra
wheels: shimano XTR, rigida shpinx, dt swiss comp
ride: very comfortable ride. absorbs vibration and small bumps very well.
power: the flex can be felt especially when off the saddle at full power (sprinting/climbing)

Specialized S-works E5
size: 50cm
ST: 46cm (C-T)
TT: 52cm
fork: Look HSC
weight(bike): 17.6lbs (8.0kg)
components: same used with the steel frame, except the front derailuer(2004 shimano 105) and seatpost(Specialized AL)
ride: fairly good ride. The frame is stiff, and can't absorb much of the bumps as compared with the traditional gemoetry frame. But because of the longer seatpost(absorbing some vibration), the ride is ok.
power: very efficient!!! I can climb faster, sprint faster, and my average speed has improved by 2kmh.

Bike frames are all about fit. If the bike fits well, it will allow you to be the most efficient you can be. I've never ridden a compact frame and don't really care for them. Nobody will ever convince me a sloping top tube is necessary. Here's another insteresting comment for you: Lance Armstrong does not ride a compact frame because he doesn't want a "girl's bike." Notice how few Trek's have sloping top tubes. Now for the editorial: They look dumb!

DEXMAX, I've got an E5 S-Works too, that bike is a weapon it sprints so well.

I've also heard the compacts described as "girls bikes".

It's not really a fair comparison: the 'S-Works' compact with the traditional CrMo. I would say the materials would have more do with the differences than anything. I have 3 aluminium bikes that are so stiff that I occasionally experience rear wheel side skipping when sprinting out of the saddle, yet they are all traditionally shaped! I also have 3 Reynolds 531 bikes (traditional) that all handle very differently. One is a 56cm that rides like well-cooked spaghetti, yet the 58cm bike is much stiffer -- i would would describe the ride as "springy". So, who knows.

I'f you're really interested, read the threads I posted earlier.

Well, I have both frame types in my stable and like both A LOT. As far as any stigma
applied to bikes, compact = "girls bike", I wouldn't be cought dead on ANY road frame with a tripple chain ring on it, Id rather walk. just my opinion........

Yeah, how fast can you go on that small ring -- 'bout 5 mph? that's walking speed anyway.

Not a roadbike but my old hardtail MTB had a sloping toptube and triple chainrings. And yeah... 5MPH is walking speed but at least I was able to ride up that twisty singletrack climb instead of walking.

Compact better for small riders.

I much prefer the traditional frame. Keep in mind that I'm average height and have typical porportions and that I'm pretty much of a retro grouch.

I much prefer the traditional frame. Keep in mind that I'm average height and have typical porportions and that I'm pretty much of a retro grouch.

I do love the look and feel of traditional geometry frames... I especially love steel frames... (Steel is real).
The ride of steel is smooth and comfy.

But i had to try a compact... (the marketing and the ads got to me :D).. And its not so bad after all.. No regrets here!

Somebody in 1 of these threads mentioned your preference has alot to do with what you are used to seeing. I am new to road bikes (coming from several years of casual mtn biking, and, before that, BMX/freestyle). As such, I am relatively unbiased, and I happen to think the semi compact geometry of my Klein (http://www.kleinbikes.com/us/road_bikes/aura/aura_x/index.html) looks "better" than frames with oldschool geometry. The "classic" geometry frames look unecessarily large to me. The Aura-X looks sexy to me, and I am a man who likes women. Lance Armstrong may be a top athlete among bicycle riders, but that doesn't immunize him from dumb jock syndrome -- his alleged "girl's bike" comment sounds rather obtuse -- not a profound or well reasoned insight into the merits of traditional vs. compact.

After reading tons of posts on threads of this topic, I have concluded the traditional vs. compact debate boils down to personal preference, with no clear cut answer.