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any frames w/ long seat tube and short top tube?(20 posts)

any frames w/ long seat tube and short top tube?kenyee
Oct 29, 2001 5:38 PM
Finally had a Serotta fit cycle fitting today to confirm what I thought about my body. I'm a mutant. Long legs. Short torso. Turns out I need a 55 c-c seat tube and 53 top tube. Interestingly, the fitter was the direct opposite; same height, but he's got shorter legs and a long torso.

Anyone know of companies that make bikes for long legged, short torsoed people? The fitter mentioned that Euro riders are built this way, but said a stock bike wouldn't fit perfectly (though using a 90mm stem would probably work ok)...
Something interesting I found out is that your "perfect fit" changes as you progress through the season because you can stretch better later on.

- Newbie (enjoying the shopping part :-)
re: any frames w/ long seat tube and short top tube?LC
Oct 29, 2001 6:05 PM
Since I am built similar, I have the same complaint about US made frames so I lean to the Euro. Look for a frame that is about square 53-54 TT, 53-54 ST or something close. The seatpost is very adjustable so the ST is not really a worry, except that the drop to your bars from the seat is larger, but this is also very Euro also. I use a 95 cm stem with slight rise or higher stack and cannot really say that there is any problems with a short stem.
Final adjustment had a drop of 1" or sokenyee
Oct 30, 2001 6:05 AM
I suspect it was more comfortable (didn't feel like I was leaning on my hands as much) because I haven't biked as long so I haven't developed my back muscles. I'm worried about neck pains w/ too much of a drop too.

He even tried setting the handlebars up 1" above the seat and that felt really weird but he said some people do it :-)
re: any frames w/ long seat tube and short top tube?jacques
Oct 29, 2001 6:24 PM
LC nailed it right on the head. Get a frame that fits you horizontally. The seatpost adjustment will take care of the vertical fit. Then work on your flexibility so you can get down on those bars way down there. Don't judge your comfort on a stationary bike. At speed and cranking out big power those low bars will probably feel better than you expect.

Colnagos are relatively short, but you need deep pockets.
You're not kidding about the deep pockets for Colnagoskenyee
Oct 30, 2001 8:07 AM
Even used prices are a big Ouch...

I checked the frame geometry and it doesn't seem to have that much of a short top tube. The seat tube and top tube seem to be close to equal. E.g., the 55cm c-t seat tube has a top tube of 54.3cm which could make it close to a 54 c-c...
Au Contrar`...Kristin
Oct 30, 2001 10:54 AM
(sp?) sorry, my French is atrocious. I have no arguement about goemetry, but Colnago does make an entry level frame. Built up with Veloce it retails at about $1500 US.
I got just the bike for you ...tarwheel
Oct 29, 2001 7:16 PM
I had a Serotta fitting and had the exact same "diagnosis." My ideal frame was a 56 seat tube and 54 top tube. After checking around, someone told me to look at the Gios frames sold by Excel Sports in Colorado (www.excelsports.com). The Gios frames, it turns out, have about as close to perfect geometry as I could find in a stock frame -- nearly as close as a custom.

Excel carries 4 Gios models -- 2 w/ aluminum frames and 2 w/ steel frames. They are all excellent frames for the money because Excel imports them directly from Italy. Gios has been making frames for more than 50 years and has a fine racing tradition. I ended up buying the Gios Compact Pro, which is sort of a retro design with chrome lugs, forks and stays and lots of other nice details. The Compact Pro and some of their other models have adjustable (and replaceable) rear dropouts that allow you to adjust the wheelbase by about 1.5 cm. My frame has a 56 seat-tube (center to center) and a 55 top tube. I have a relatively short stem to make up the difference.

Anyway, the frame fits me great and for the first time I don't feel too stretched out when riding. I've had the bike about 5 months and I've put 2,500 miles on it during that time. All of the Gios models are cobalt blue, which is sort of their trademark (like celeste green Bianchis).

Short of a custom, the Gios comes the closest to the type of geometry you mentioned. Colnagos are relatively short across the top compared to many frames, but are still a little longer than Gios. I have also heard that De Bernadino (not sure if I have that spelled right) also makes frames with relatively short top tubes. GVH Bikes (www.gvhbikes.com) carries some of the deB frames.

Good luck.
maybeDA
Oct 30, 2001 4:39 AM
I don't think 4" of spacers under the stem would be considered an ideal fit. For the original poster, you also need to remember the seat tube angle- steeper means a more effective TT length and most stock bikes with short TTs have steep angles so it all works out about the same. Serotta size cycles fittings give you the BB-bar coordinates (vertical and horizontal protrusions) for this reason. My guess is that you need a short TT and steep angle, and that isn't common in stock frames. At the very least you prob need a minimal layback post. If you're way out of the norms custom may be you best option and good quality steel from a local builder can be had for under a grand. A WSD-type frame amy also work. BTW, Serotta fittings often seem to be "short" so consider your present bike and comfort.
Huh?tarwheel
Oct 30, 2001 5:01 AM
What does the amount of spacers have to do with it? BTW, I have about 4 cm (not inches) of spacers on my bike, but that has nothing to do with a proper fit or lack of it. (If you are basing your statement on the photo of my bike in photo section here, that shot was taken soon after I got the bike and before I had installed a positive rise stem and trimmed the steerer tube.) I like my handlebars about 1" below my saddle, which is not unusual. In my case, it's because I lack the flexibility to ride in an aggressive position with my bars far below my saddle. I also don't find it comfortable, and have trouble seeing the road ahead without craning my neck. A higher bar just looks different with a threadless stem. With a threaded/quill stem, no one would even notice.
I looked at the picturejj
Oct 30, 2001 5:07 AM
and there is NO WAY you would be able to get your bars that high with a normal quill stem. You could use a Nitto Technomic, but those still look ridiculous.
forgot to mention the seat tube angle was left at 73 degreeskenyee
Oct 30, 2001 5:58 AM
on the fit cycle measurement,
He said it was "average" for road bikes.
STA...Questions questions questions...Kristin
Oct 30, 2001 11:01 AM
Okay. When dealing with long femurs (need for longer ST than TT), which is more ideal: Make up the difference with a shallow STA or longer crank arms?

I hear alot of debate about Seat Tube Angle, but I rarely hear anyone mention its relation to KOPS and leg length. Is this an important consideration or no?
re: any frames w/ long seat tube and short top tube?jaybird
Oct 30, 2001 5:51 AM
not to mess with your ego, but you might look at some of the bikes designed for women. They generally have a shorter top tube relative to the seat tube. Colnagos are notoriusly short on the tt as well.
Thanks for Colnago ref and tarwheel's Gios refkenyee
Oct 30, 2001 6:01 AM
I guess now I have to look into Euro bikes if the fitter was right about Euro riders having a similiar long leg/short torso phsyique.

BTW, I don't have much of an ego, so I'll try anything as long as it's comfortable and fits. I consider myself a skinny stick w/ long legs... :-)
TT length meaningless without STAC-40
Oct 30, 2001 9:02 AM
You didn't get a decent fit if they didn't give you an optimum seat tube angle to go with that TT length. A bike with a 73 degree STA and 54.2cm TT is effectively the same as one with a 53cm TT and 74 degree STA. Only the nominal saddle position on the post changes.

The TT length must also be qualified with a particular stem length. A 120 stem isn't more correct than a 110.

An optimum head tube length should also be determined, to avoid the need for lots of spacers or a high rise stem.

The fit bike should also have the same style of seatpost, pedals, bars and saddle that you intend to use. If not, the custom fit could easily be off by 2cm.

I also have long legs and short torso (5'-7" with 83cm inseam). A 55cm (c-t) Colnago fits great with a 110 stem.
The STA was 73 degreeskenyee
Oct 30, 2001 10:42 AM
He changed it at the very end to try out 72 degrees but the 72 didn't feel as comfortable.

He was trying to find a TT length that allowed the most variation in stem length (I think); he seemed to be trying to find a top tube that allowed an adjustment of +- 1cm on the stem.

As for the type of seatpost, pedals, bars, saddle, he didn't mention anything about them; he also didn't mention a head tube length. It was a Serotta fit cycle (I saw a pic of one on ebay before I went and it looked just like it). The guy has also done Serotta fits.
BTW, my inseam measurement was also 83cm. What has me also puzzled is that the calculation on a web site (Add your arm length and your torso length, divide by 2, add 4. This gives you your combined top tube and stem length.) gives me a theoretical top tube of 57cm.
Where did you get the relationship between STA and TT length?
get a custom. nmcolker
Oct 30, 2001 3:09 PM
nm
Other info on the measurement sheetkenyee
Oct 30, 2001 3:17 PM
Finally remembered to bring the sheet home :-)

Stem length 95-115mm
Crank arm 172.5mm
Handle bar width 44cm

Seat tube angle 72-73 degrees

The measurement sheet doesn't even have a field for head tube length..only head tube angle and it wasn't listed since I didn't get sized for a custom frame (at the end, I wondered if I should have, but a newbie probably shouldn't get a custom frame as a first bike in 20 years...)
TT & STA relationshipC-40
Oct 31, 2001 5:25 AM
As an engineer, calculating the effect of STA on TT length is pretty simple. Assuming that saddle height is .883 times inseam, the change in TT length is saddle height times (cos73-cos74). Steeper seat tubes effectively lengthen the top tube, once the saddle is moved back to achieve the same KOP. Any two angles can be put in the formula to compare different frames.

For an 83cm inseam, the result of the formula is about 1.2cm. Saddle height may be a little more or less than .883 times inseam, depending on the type of pedal/shoe combo, you're preferred foot position at the bottom of the stroke, and how accurately your inseam has been measured.
Thanks...kenyee
Oct 31, 2001 7:03 AM
Forgot about the origin of the .883 number...

So, since the GIOS has a 74 degree STA, the top tube is not really shorter than normal since other frames have a 73 degree STA. It's just a square frame (ST = TT length) like the Colnagos (55 c-c frame has 55.6 top tube w/ 73 degree angle) because the 74 degree Gios TT of 54 on the 55 c-c ST is really equivalent to a 73 degree TT of 55.2)...