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  1. #1
    Cries on hills supton's Avatar
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    Touring Bike Geometry

    My current bike is a 53cm frame, but with a 57cm top tube. I'm thinking that, since this is a mid 80's bike with stem shifters and suicide brakes, that it may have been designed to ride the tops comfortably. My question would be, would this sort of stretch make for a reasonable touring bike? I'm finding that I enjoy longer rides, but found my neck and shoulders felt kinda beat after a long ride recently. Could be conditioning, I will grant; and I am starting to redo the fit: but would this bike be more amenable to my wants? For comparasion, I've been wrenching on a 53cm World Sport (top and seat tubes), and it feels twitchy by comparasion, yet the Panasonic is only maybe 2cm longer on the wheelbase.
    '07 Trek Pilot 1.2
    '85 Panasonic Sport 1000 (beater, gone now)
    '69 Raleigh Sprite 5 speed (AW instead of S5, for now)

  2. #2
    jcm
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    Not enough info. But, here's how I do it - and it usually doesn't have much to do with a guy in a shop telling me, "there, now you're comfortable." when I'm not.

    Assuming a standover with just a touch at the fruit basket, I start with a saddle that I like. For me, it's a Brooks 17 on a roadie. The bars are about an inch above the highest point of the saddle. The saddle is set so there is no perineal pressure. That means a bit of an up tilt with the Brooks, and it's slid forward so my sitbones are upright, with a little forward arch to the lower spine. The bars are adjusted so that my elbows are slightly bent, allowing for road shock to be dissapated there - not at the shoulders or collar bones. In order to achieve that, I might install a shorter stem, while keeping the quill high.

    In other words, with a longer bike, I compact the cockpit and I'm still able to enjoy the sedan-like ride of a bigger bike. The Knee Over Pedal fitting is a go-by, not a hard fast rule. It gains in importance wirth teh level of cycling you require - such as with a racer. Or, if you use higher gears on hills alot, you might want to pay closer attention to it. If you select gears that fit your comfort level, KOP is not so important - just don't get too far away from it. Shorten the cockpit by shortening the stem first. Then, sneak up on it by moving the saddle forward. On some bikes, a short stem will cause the bike too "wallow" in the turns. I don't worry about that because I don't require such crisp, race-like handling. Besides, most of the time I'm going straight down the road. A nice sedan should wallow a bit

    Both my roadies are too big for me, but they treat me well on some very long rides.

  3. #3
    Cries on hills supton's Avatar
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    Well, bike wasn't from a shop; and after tweaking it so it felt ok and going 660 miles, I'm going to PT tomorrow. At the moment, I don't trust myself. I'm playing with the fit today, as I have the day off.

    If I pull hard (but carefully!), I have about an inch of clearance. So, frame size, check. Saddle, not really. It's what came with the bike, and it is minimally padded; but it's no Brooks (not that I've had one). After a couple of rides though, my bottom seems ok with it. Couple of saddle sores, but that's it (and that has more to do deal with clothing). I did have the seat cranked all the way forward, come to find out; I pushed it all the way back, and I'm about at KOPS.

    The 18.5% of femur length rule does indicate that I ought to be using 160mm cranks though (currently 170's). Maybe I'll try a (short) trip today, and see if all the changes matter--maybe I've been running the seat too high to deal with too long cranks, or to deal with tight calves, not sure. I do know I've had a problem with one foot hitting the crank (at the crank spindle), so I'm guessing that may have pushed me to where I was. In the end, I'm worried that pushing the seat back will make the reach worse.

    I suspect I do want a different stem, but haven't gone shopping for one yet. This one has always been about 3cm below the saddle (or more--am going to experiment with lowering the seat, plus todays pushing the seat back), and it is already at the max. I measured the stem, and it's 8.5cm from max to to top of stem, and 8.5cm from center of the bolt to center of the handlebar clamp. So, do they make stems (traditional stems for threaded systems) that would allow for that kind of height? Shouldn't the handlebar clamp still be centered over the wheel axle?

    Anyhow, sorry, this is more "fit" than "touring geometry".
    '07 Trek Pilot 1.2
    '85 Panasonic Sport 1000 (beater, gone now)
    '69 Raleigh Sprite 5 speed (AW instead of S5, for now)

  4. #4
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    A bike designed for loaded touring usually has long chainstays (around 17 inches) to provide room for saddle bags that don't hit your heel, and a long wheelbase (41 or 42 inches) for stability and comfort on rough roads.

    For your own comfort while touring, you would benefit from using the fattest tires that fit, and raising the bars so that the highest portion of the bars is level with the top of the saddle.

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    Don't get too locked into rules like that 18.5 percent-of-femur thing, nor into KOPS, either. Many people have abandoned KOPS altogether, or use it as a starting point from which they can adjust. I may have lucked out on the fit of my two bikes (Atlantis and Rambouillet), but I built them up myself, rode them for a week, made a few tiny adjustments (slid one seat back, put on one taller stem) and I haven't had to change anything in thousands of miles.
    Sometimes I think we overmystify bike fit. There may be an ideal setup for racing, but even then it would be ideal for the individual rider, not for ALL riders without considering the differences in their bodies.
    Set the thing up so it's comfortable and go ride it. It makes a lot more sense to fit the bike to you than you to the bike, especially if you're not able to train six hours a day to adapt to some "ideal" position.
    If you need a taller stem, check www.rivbike.com. Rivendell still uses quill stems and sells several sizes.

  6. #6
    Cries on hills supton's Avatar
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    I'm trying not to be locked into those measurements, but I figure they are good starting points. Yesterday, I messed with the bike on the trainer. Didn't take long to find out my issue: I had set the seat too high (about 1.5cm, maybe 2), but my hips were not rocking. Instead, my ankle would toe down quite readily on the bottom of the stroke--hence, my issues with my calves of late. After sliding the seat back (not the same as a setback seatpost, but that was recommended by one of the sites), and then setting the height to 18.5%, I took a ride. Maybe marginally faster, but overall similar, except I finally got something of a workout in my thighs--in 660 miles, starting as a noob, I've never had sore thighs, until yesterday. But my calves for once aren't bothering me, and I can walk today.

    I'm going to look for a different stem; I pulled mine up 1cm past the max (which is to say, 1cm higher than before), and it's now about 2cm below the saddle. Hard to say if it's alot better or not; but I can tell I really want another. Have started shopping for that. But first I'll probably have to figure out the head tube angle and see what kind of reach I want to aim for (other than "shorter").

    As for tires, I've been running 27x1 1/4 (32mm wide), at 90psi they are a bit rough, but ok. Can definately feel the flat spot at high speeds (rim has a flat spot). At 60psi they are quite smooth though.
    '07 Trek Pilot 1.2
    '85 Panasonic Sport 1000 (beater, gone now)
    '69 Raleigh Sprite 5 speed (AW instead of S5, for now)

  7. #7
    Senior Member halfspeed's Avatar
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    Quote Originally Posted by supton View Post
    My current bike is a 53cm frame, but with a 57cm top tube. I'm thinking that, since this is a mid 80's bike with stem shifters and suicide brakes, that it may have been designed to ride the tops comfortably. My question would be, would this sort of stretch make for a reasonable touring bike? I'm finding that I enjoy longer rides, but found my neck and shoulders felt kinda beat after a long ride recently. Could be conditioning, I will grant; and I am starting to redo the fit: but would this bike be more amenable to my wants? For comparasion, I've been wrenching on a 53cm World Sport (top and seat tubes), and it feels twitchy by comparasion, yet the Panasonic is only maybe 2cm longer on the wheelbase.
    57 cm seems unusually long for a 53cm frame. How are you measuring that?

  8. #8
    Cries on hills supton's Avatar
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    Center of seatpost tube to center of head tube. I haven't tried yet to get tube angles.
    '07 Trek Pilot 1.2
    '85 Panasonic Sport 1000 (beater, gone now)
    '69 Raleigh Sprite 5 speed (AW instead of S5, for now)

  9. #9
    Senior Member halfspeed's Avatar
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    57cm top tube wouldn't be out of line for a modern compact 53cm seat tube, but on a vintage bike it's a bit unusual.

    More important than the wheelbase for "twitchiness" is the trail. Check Sheldon's glossary for an explanation.

  10. #10
    Violin guitar mandolin
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    What is "touring" in your mind? Certainly for carrying weight a traditional model might be in order. For example, I used to tour on a bike more or less like: 22" x 21.5", 72 parallel, 17" chainstays, 2" rake, 100 mm stem, set with perhaps 1 cm drop, relatively low bottom bracket, wide double on the front, 700C tires. With a front rack as well sometimes. Nice traditional approach. Every now and then I'd get annoyed at the thing and go on a tour with my racing bike. 73 parallel etc, standard 1970s stage race bike. It worked fine, too. More drop to the bar, I tended to ride harder, and I didn't carry as much. Had to use P clamps. Otherwise, it worked great. Didn't have as low a low, so I'd muscle the hills. I can't really say one was better than the other loaded up!

    Now I would "tour" with a handlebar bag, a big seat bag, and credit cards. That's a different world. I would go on a long tour with . . . . my normal road bike. Which is an Italian carbon bike, pretty stiff, very comfortable, has 72.5 head angle that gives nice carved turns. I can ride that all day, so why have something different?

    If I were running coast to coast or the like I'd try a bunch of things. Don't know what I'd end up with. Probably something compact, but not particularly short, and set up with lowriders front and back. Wouldn't be surprised to end up with a custom, at least as far as bag placement.

  11. #11
    Cries on hills supton's Avatar
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    "What is touring in my mind?" Good question. Not there yet. I sincerely doubt I'm going to get into fast riding; but I enjoy pounding out miles--well, so far at least. The most I've ridden in one shot was 48.7 miles, and it was great. Loved it, even though I was wiped out at the end and could just barely make the last 8 miles home.

    I don't know if I will get into "touring", as in, carrying enough stuff to camp out for a week. But I think I want a comfortable ride, that I could enjoy for a typical 3 hour ride. I relish the idea of doing centuries next summer. Maybe, some day, I would do a mini tour of some sort; but I don't think it's in the cards for a few years.

    Anyhow, touring bikes seem to be expensive (to me who's riding a $5 bike); and I'm loathe to just buy one just because it's a "touring bike". I guess I'm just after generalizations; I know that the bike that is right for me will be whatever feels right and racks up miles. I just haven't taken 32 different bikes out for 4 hour rides to see what feels "right".
    '07 Trek Pilot 1.2
    '85 Panasonic Sport 1000 (beater, gone now)
    '69 Raleigh Sprite 5 speed (AW instead of S5, for now)

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