Horizontal vs. Sloping top tubes - what do we think?

[simon.r]

I ride a frame with a 57cm horizontal top tube (centre to centre) and a 61cm seat tube (centre to top). I have about 18cm of seatpost showing.

A different frame from the same manufacturer has a effective top tube of 57cm and a seat tube of 53cm, so I'd need about 26cm of seatpost showing.

From a purely aesthetic point of view I much prefer the horizontal top tube and not too much seatpost showing, but if I'm looking for a new frame that severely limits the choice.

Why are sloping top tubes so prevalent at the moment? Is it just fashion or are there practical reasons?

 

[Pale Rider]

I prefer sloping top tubes for the same reason you prefer horizontal - aesthetics.

But I'm not aware of any practical reasons for one or the other.

Tempting to say standover clearance is better on a sloping top tube frame, but when I hop forward off the saddle I'm close to the head tube so the top tube may as well be horizontal.

 

[kiriyama]

I prefer horizontal. Aesthetics I suppose, bit more of a classic style.

 

[dan_bo]

The original argument for sloping frames was the smaller triangle provided a stiffer structure whilast the longer seatpost dulled vibration mre effectively. I can see the point.

For what it's worth, I like both.

 

[Vapin' Joe]

Sloping gives you one less dimension to worry about, you only have to concern yourself with top tube length. It also means manufacturers can offer a smaller range of sizes which keeps costs down for them and ultimately for us. It is worth noting that many pro teams now use frames that are from stock rather than each rider's being custom made.

 

[Bollo]

My old litespeed has a horizontal top tube that looked old fashioned when I bought it as sloping top tubes were just taking off. I still think its quite handsome.

 

[Bollo]

For sheer ugliness, this takes some beating. When I acquired it, I found it only had about an inch and a half of seatpost in the frame as well. It's been rehomed now (with a longer seatpost).

View attachment 125798

Aaaaarrgghhhh! My eyes!

A step-through kinda hybridy MTB. The world's gone to hell, TMN. To hell.

 

[simongt]

According to the late Richard Ballantyne, sloping top tubes are a development of the mountain bike. The idea was / is that with a sloping top tube, when one is belting up and down 'mountains' and the bike is moving around under you, it gives you more manoeverability, thus control. Also, if you come to a sudden stop and slide off the saddle onto you feet, it is less likely to be an eye watering experience. Well, for men at least.

 

[3narf]

Smaller triangles = more stiffity between head tube via BB to back wheel spindle. The seatpost can then provide a degree of flex ergo comfort.

Back in the '70s (I choose this decade 'cos that's when I grew up) and prior, the idea was the biggest possible main triangle as that took out a bit of the harshness. Aluminium components were relatively weak, flexible and inconsistent, so the exposure of the seatpost etc was purposely limited.

Please correct any of this; I'm making it all up as I go along!

The point I was going to make is that with modern technology and materials, a well-designed and executed bike can have either. Imo a modern-looking carbon or ally bike looks better with some slope; horizontal top tubes seem more natural with skinny, steel tubes.

Having said all that, I'm intending building a steel road frame with a sloping top tube...

 

[raleighnut]

Sloping top tube allows a longer head tube on the same size frame, stiffens it up laterally.

 

[ColinJ]

Also, if you come to a sudden stop and slide off the saddle onto you feet, it is less likely to be an eye watering experience. Well, for men at least.

I suspect that most women would probably find that an 'eye watering experience' too!

 

[MichaelW2]

With sloping top tubes, short arsed riders with long torsos can fit better. With a selection of seatpost laybacks and stem length, fewer frames can fit more riders. Giant used to do this with the original TCR, but I think they dropped this service.

 

[Accy cyclist]

My Scott expert bought in 2000 was my first sloping top tubed bike.

(Not my bike but 95% like it) The colour scheme looks a bit dated, don't you think?

I prefer sloping but don't mind horizontal top tubes.

 

[cyberknight]

http://www.cyclingweekly.co.uk/news/latest-news/icons-of-cycling-giant-tcr-206346

 

[Blue Hills]

I suspect that most women would probably find that an 'eye watering experience' too!

Now now colin, stop trying to be so "new man" not quite the same is it?

On main topic, i can see that horizontal looks more classic and even more aesthetically pleasing. For practical purposes i much prefer sloping, and am prepared to accept that when you stand well back from my bikes and look at them they do look somewhat odd/not big enough. In short, i prefer the ride and sod how the bike looks.