|'Idiot's Guide' question for ET (or anyone who can answer)||steeveo|
Aug 8, 2001 5:17 AM
|Of the two methods you described for determining reach (pinky over the middle of the bar and eyeballing the hub from the drops) which is the better indicator of good fit? My pinky's dead-on, using your technique. But to conceal the hub I'd have to extend my stem a couple centimeters. If I did THAT, my pinky would be a couple centimeters short of the bar.
Get my drift? I either have a too-long torso or too-short arms. Which indicator would you go with in a case like that?
Aug 8, 2001 6:08 AM
|There is one more check you can make: the Excel method. First, measure your torso from your crotch to your sternal notch. Then, measure your reach from the inside of your armpit against your ribs (this will not be very comfortable) to the middle of your hand. I have created a quick webpage illustrating these two methods ( http://www.azaleacitycyclists.com/fit.html ). The illustrations are not mine and I cannot recall where I got them. Then, add these two figures together, divide by 2, and then add 4. This is a good starting point for your overall reach. For example, my overall reach is 68.5cm. I could go with a 56cm top tube and a 12cm stem or a 56.5cm top tube and a 12cm stem...you get the idea. |
Also, your reach will be affected by your flexibility. I have heard that if you can bend over and place your palms on the ground, then you can add 1.5-2cm to your overall reach. If you can touch the tips of your fingers to the ground, then you can add about .5-1cm to your overall reach. Again, use these comments/suggestions as guides and not something that is to be strictly followed.
As for the stem obscuring the hub, there are different views on this. But, as long as the stem obscures the hub or is a little behind the hub, then you are in the ballpark. The following info is from the USCF: "Stem Extension: The length of the stem extension determines the horizontal distance between the handlebars and the seat. To determine a proper stem extension. assume a normal riding position with your hands on the brake hoods. Have a helper drop a plumb line from the tip of your nose while you look down at a 45 degree angle toward the road surface. The line should pass about one inch behind the handlebar. A long ride can also give you evidence about the stem extension. If you develop soreness in the triceps and deltoid (upper arm) muscles, the stem extension is too long. A short stem will cause your neck and trapezius (shoulder) area to ache. Women generally need stem extensions in the 80 to 110mm range (measured from the front edge to the back edge), while men's longer arms accommodate 90 to 120mm lengths.
I hope this helps.
Aug 8, 2001 7:31 AM
|I think all these rule-of-thumb are very important for beginner. It allow the beginner a good starting point. On doing "a long ride" to get "evidence", would you recommend doing most of the ride with hands on the hoods? I usually spend most of my time with my hands on top of the bar on a long ride. Maybe my existing stem is too long. |
|Not sure, but...||PsyDoc|
Aug 8, 2001 7:38 AM
|...I spend most of the time riding with my hands on the hoods or somewhere on the top of the bar. I would suggest that when getting evidence you ride in your "normal" position. Perhaps others can add a differing opinion.|
|I think that what all these methods and rules of thumb show||bill|
Aug 8, 2001 6:56 AM
|is that there is no magic scientifically reliable formula or method that will work for everyone, everytime. They are rules of thumb, and they are nothing more or less. They are no substitute for trying it out, living with it for awhile, and maybe trying something else. When you realize that you pretty easily can adjust your stem length by 3 cm or more, and I'm not sure that total length is really the most critical measurement, anyway, at least in part because your comfortable length can change, I think that all of these methods and measurements and decimal points and formulas are helpful to a point but really can be overemphasized. |
If it hurts, try something else. Don't buy an expensive stem (or a custom frame) until you're pretty darn sure.
|I think that what all these methods and rules of thumb show||Jon Billheimer|
Aug 8, 2001 8:01 AM
|This is an interesting discussion. Over the years I've modified my own position on the bike considerably, due to increased mileage, fitness, and flexibility. I tried the arm/pinky method and found my pinky about two centimetres short of the handlebar. But then I also am very flexible. At the same time,if I look down, the bar obscures my hub. I also ride with a 10 cm saddle/handlebar height differential. Interestingly,I did my latest setup according to a German engineering firm's software program for fit based upon multiple measurements of limb and torso length. According to their formulas, my very aggressive fit/body position is right on. It also feels very comfortable and efficient. |
However, I do agree that these measurements are going to vary considerably depending on one's relative body proportions, flexibility, and riding style. The most important things here are comfort, and bike handling. A grossly improper weight distribution between the rear and front wheel will obviously make the bike twitchy and dangerous on descents and cornering. I think more novice riders err on the side of too short top tube/stem combinations and low saddle heights.
|indicators are just that: indicators||ET|
Aug 8, 2001 8:41 AM
|The rest is going with how you feel. How do you feel? (Is this on your current bike or one you test-rode?) You may also want to post what your current stem length and spacers are. The pinky dead-on is a very good start and a great ballpark device, especially for those without a clue and trying to zone in on top tube or trying to decide whether to test-ride or not. (I'd expect seasoned, flexible riders either to come out a bit long, or at least have a more severe drop to the bars.) While riding, the hub test is another nice check. I noticed you defined the hub test as "eyeballing the hub from the drops". I think more define it as eyeballing the hub from the hoods. How do you come out on the hoods? You may have noticed that I intentionally omitted my own hub test definition, as that is not for me to say. The seat/bar differential and your flexibility matter as well. If one has a rather big seat/bar differential, the horizontal distance is probably not as long. If someone has great flexibility, that adds to length. On my current setup, which I am happy with, I'm more than a cm long on the pinky test, satisfy the hub test in the drops, currently have a 2.8" seat/bar differential (but plan to soon experiment with taking off a one-cm spacer) and am very flexible (hands on ground). But I could see that bringing the horizontal reach in a drop and going down vertically would also probably work, and these would alter the tests a bit, i.e. the pinky might then be dead on.
To reiterate, the purpose of the "idiot's" guide is to get people close, and the rest is up to them. My claim is that for those without a clue, it might be just as useful as the Serotta size cycle, and hopefully (with the other details included) will aid in avoiding a major mistake, which I think is more common than might be believed. To that end, in a nutshell, what I basically described is to get seat tube by comparing standover to inseam (which I'd prefer to describe as medium pressure and not, as one poster claimed, all the way and very hard to pubic bone--ouch!--but I'm suspicious that many newbies posting here get their inseam way wrong and short because they use little or no pressure at all), and then zone in on top tube with these two tests. I am not claiming a magic formula to work exactly for everyone, especially in light of all the variables (experience, seat/bar diff, flexibility, etc.). I agree with the other posters that these are general indicators. That's all. And don't ignore the other details of the "idiots" guide, e.g. taking a long ride, and stem/spacer considerations.
For your case, and as suggested in the "idiots" guide, here's a simple test: swap the stem to one cm longer. Go for a reasonably long ride or rides and see how it feels. (Sure, it might take some time to really get used to it, e.g. for very long rides, but you probably can tell if it's a definite no. I'd err on the side of shorter if one already has aches and pains due to lack of flexibility or too severe a drop.) If you really like it (less air resistance too!), ask yourself if the stem still makes sense for that size bike. If it's on the longish side, a bike with a longer top tube may be more ideal.
Aug 8, 2001 9:08 AM
Aug 8, 2001 10:32 AM
|Thanks. I'm bookmarking that site and will study it in more detail later. At first glance, it does look pretty good. I don't know about better, though--it relies on formulas which, as with much else, tend to give a skewed picture at the extremes, and more important, it sure ain't no "idiot's" guide. How many will really take all those measurements (even though they're not that hard to do), and especially how many newbies about to buy their first real road bike?|
|indicators are just that: indicators||steeveo|
Aug 8, 2001 9:20 AM
|Thanks for a thoughtful reply.
I said 'hub viewed from drops' because I believe that's what Colorado Cyclist suggests. I too had always thought it should be from the hoods. But I've heard both. From the drops, the hub on my bike may or may not be obscured depending on whether I'm scooted up or back on the saddle.
This is my existing bike, which I've ridden comfortably for 10 years except for some knee/elbow overlap in the drops (a position I rarely use). I've always suspected, though, that I'd be better off with a bit more reach, and was prepared to try a longer stem extension next time I had the bike in for an overhaul. I was surprised when your pinky test showed I was probably not that far off. But then 10 years without back or neck pain should have been a pretty good tipoff that things weren't too skewed. Thanks again.
|if it ain't broken...||ET|
Aug 8, 2001 10:44 AM
|OTOH, to find out if you might like it better with a longer stem, or if you have specific priorities (e.g. to eliminate knee/elbow overlap, or to cut down on air resistance, which is substantial), you could give it a try for a while.
RE: knee/elbow overlap. Raising your stem (not sure you want to do that) may solve the problem. While one normally would rather evolve towards a lower, not higher position, the fact that you rarely use your drops is a good reason to consider raising it, because then you'll use the drops more. I think it's a shame to use the drops only rarely. You could even consider a stem one cm longer but angled more up; the possiblities are endless! Another idea is to switch to wider handlebars.
OTOH, 10 years without pain... :-)