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Frame Size(5 posts)

Frame SizeJM714
Dec 23, 2003 3:09 PM
I'm 6'5" and looking for a bike. Any thoughts from people 6'4" to 6'6" on frame size? What are you riding? I've been to numerous shops and no one has a 63 on the floor to ride. They all say they don't usually carry something that big. I'm thinking of a 'XL' Giant TCR, 63cm Trek 2300, or a 63cm C'dale R1000.
cycling inseam...C-40
Dec 23, 2003 4:07 PM
is the key to determining frame size.

Read up on bike fitting a www.cyfacusa.com.
It's not just about your total heightKerry Irons
Dec 23, 2003 4:26 PM
Measure your inseam: stand against a wall with your feet 6 inches/15 cm apart. Push the spine of a 1 inch/2-3 cm thick book into your crotch with significant pressure, and measure the distance from the book spine to the floor. Your saddle top to pedal axle should be 108-110% of the inseam measurement.

Here are several frame fit calculators.

http://www.bsn.com/cycling/ergobike.html
http://www.coloradocyclist.com/BikeFit/index.cfm
http://www.sheldonbrown.com/harart-frames.html
http://www.rivendellbicycles.com/frameinfo/Frame_Sizing.htm
http://www.peterwhitecycles.com/fitting.htm

For adjusting the fit of the bike, there are roughly five starting points:

1. Seat height (top of saddle to center of pedal axle) at 108-110% of inseam.
2. Saddle parallel to ground.
3. Saddle fore/aft adjusted so that a plumb bob from the bony protrusion just below the kneecap passes through the pedal axle when the cranks are horizontal. This is known as KOPS (Knee Over Pedal Spindle)
4. Front hub axle obscured by the handlebars when riding in your "regular" position (drops, hoods, or tops).
5. Top of handlebars 1 to 4.5+ inches below the top of the saddle depending on your flexibility and size.

To measure your knee over pedal spindle (KOPS) situation, drop a plumb line from the front of the bony protrusion just below the knee cap.

These are all starting points for "average" proportioned people, and many folks like to move away from these starting points as they learn what makes them more comfortable, powerful, or efficient. You want to get the fit of the frame as close as you can, then do minor adjustments with the stem, seat post, saddle position, etc.

A lot of this is personal comfort, and we all tend to adapt to a given position over time. For example, a given stem length may be right for you, but it may feel long at first. I use the "handle bar obscures the front hub" rule for my fit, but others claim better position (for them) with the hub in front of or behind the bar. I'm 6' tall and ride with 11.5 cm drop from saddle to bar, probably more than most people would like but fine for me. Some are suggesting zero drop from saddle to bars - it's about comfort, efficiency, and aerodynamics. The ERGOBIKE calculator is pretty good, but it is not infallible. I would suggest riding some miles (over 100 total, and over 500 would be better) and see if you adapt to the position. There are no hard and fast rules, just general guidelines, when it comes to these things.

Just as important as your size is your flexibility. If you have a stiff lower back, you may not be able to lean over and stretch out as much. If you are very flexible, you may get away with a longer top tube, with the stem in a lower position. Over time on the bike, too, you may become more limber, or at least become accustomed to being lower and stretched out. So, your first 'real' bike may not be anything like what you will want 5 years from now.

Someone new to road riding is highly unlikely to find their ultimate position on the first go. As they become accustomed to the riding position and get some miles in, sometimes over several seasons, people often find their desired position changing. What was "stretched out" now feels OK, or what was "just right" now feels cramped. With time, if you are working on your position along with all your other riding stuff, seat position tends to rise, handlebars tend to be farther below the saddle, saddles tend to move rearward, and handlebars tend to be farther forward from the saddle. You simply cannot say "this is the right position for someone of your body dimensions" because there are too many variables and things that change with time. Get used to your position, and then occasionally make small changes: raise/lower your saddle, move your saddle forward/backward. Ride a while with the changes (a few 100 miles, anyway) and decide if it is better or worse. If it
re: Frame SizeGrahamalicious
Dec 23, 2003 9:46 PM
I'm going to be (within the next few weeks) selling new a 63cm 2002 Trek 2300 Custom painted Frame/Fork/Headset Really soon if you're interested in building your own bike...

grahamalicious at mac dot com
Here's what you want . . .Drone 5200
Dec 23, 2003 11:28 PM
this topic was discussed a couple of months ago. This link will give you some ideas.

rockstar "TALL RIDERS" 11/12/03 1:46pm

As you can see, there is some variety in what tall guys like to ride. Everyone is different.

The 63cm is in the balpark for you, but you are going to need to test ride to be sure. Don't be shy about asking the LBS to bring a bike in for you to test ride. The LBS where I picked up my 5200 (62cm) had no problem bringing in a 63cm 2300 for me to compare to the 5200. Ask around.