How do you know if a bike fits?
#1
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How do you know if a bike fits?
This may be an open ended question but how do you know if a bike fits? I rode 54cm and 52cm Treks and could not really tell a significant difference besides the fact that I felt slightly higher up on the 54cm. On the 54cm, standing with the top tube between my legs, I had just mm's of space but it still felt OK. The 52cm felt OK also but I felt like I was riding a kids bike. I dunno maybe it was my inexperience or psychological.
Note the 54cm Trek (Domane 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
Note the 54cm Trek (Domane 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
Last edited by yashinon; 04-23-16 at 07:54 AM.
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For me, it's when I can sit comfortably on the saddle and rest my hands on the hoods, with a bit of a bend in my elbows, without feeling too stretched out or too cramped.
In other words, it's all about the top tube. Get that right, and the rest can be adjusted to fit.
In other words, it's all about the top tube. Get that right, and the rest can be adjusted to fit.
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This may be an open ended question but how do you know if a bike fits? I rode 54cm and 52cm Treks and could not really tell a significant difference besides the fact that I felt slightly higher up on the 54cm. On the 54cm, standing with the top tube between my legs, I had just mm's of space but it still felt OK. The 52cm felt OK also but I felt like I was riding a kids bike. I dunno maybe it was my inexperience or psychological.
Note the 54cm Trek (Madone 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
Note the 54cm Trek (Madone 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
There are all kinds of ideas in bike shops about fit, many of them wrong. I've heard it many times (to take just one example), that the front of the kneecap should be vertically over (or very close to vertically over) the pedal spindle, when the pedal is at the 3:00 position. This is taken as science. The more appropriate term is BS. Here is a good demystification by Keith Bontrager:
https://www.sheldonbrown.com/kops.html
Here is another: https://hypercatcycling.wordpress.co...pedal-spindle/
To paraphrase someone on another recent thread, "The bull**** is a little thick in this part of the pasture."
It's best to get your science from people like Bontrager, not from your typical non-scientific bike shop or youtube video.
His article would make a good study.
Last edited by lightspree; 04-22-16 at 10:04 PM.
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Much of what you said in your post, OP, made no sense. Your three contact points, saddle, pedals and handlebar shoule be in exactly the same relationship on both the 54 and the 52 so the salesperson's comment is nonesense. Your leg should look the same on both bikes. If it doesn't, it is because the shop didn't set you up correctly. Similarly you should not have felt higher up on the 54, because you should have been the same distance from the pedals on both bikes. Having said that, my belief is that the 52 should be the right size for you, but you really need to confirm that by a long test ride.
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Another question the OP might ask is, How Do You Know If a Given Bike is Properly Fitted or Set Up for You?
If you changed the stem on either bike, the fit would be different. It isn't just the bike that fits or doesn't fit; to a great extent, it's how that bike is fitted or adjusted to fit you.
The saddle can be higher or lower. The stem angle can bring the handlebars up or down. The stem length can bring them closer or farther away. The saddle can slide forward or back on its rails. Different handlebars can be shaped more or less to your liking. The stem can be clamped on higher or lower, by adding or removing spacers....
I would start with 52cm and smaller bikes, get the shop to make some adjustments, try to dial things in (you will learn more the more you experiment) and test ride until you feel a sense of a great fit.
Some bikes have longer top tubes than others, even among 52cm bikes. Shorter top tubes will usually allow for a more upright position. Comfortable positions are often different from aero positions, and it is helpful to know whether your main goal is comfortable recreational riding or more competitive, speed oriented riding.
If you changed the stem on either bike, the fit would be different. It isn't just the bike that fits or doesn't fit; to a great extent, it's how that bike is fitted or adjusted to fit you.
The saddle can be higher or lower. The stem angle can bring the handlebars up or down. The stem length can bring them closer or farther away. The saddle can slide forward or back on its rails. Different handlebars can be shaped more or less to your liking. The stem can be clamped on higher or lower, by adding or removing spacers....
I would start with 52cm and smaller bikes, get the shop to make some adjustments, try to dial things in (you will learn more the more you experiment) and test ride until you feel a sense of a great fit.
Some bikes have longer top tubes than others, even among 52cm bikes. Shorter top tubes will usually allow for a more upright position. Comfortable positions are often different from aero positions, and it is helpful to know whether your main goal is comfortable recreational riding or more competitive, speed oriented riding.
Last edited by lightspree; 04-23-16 at 12:47 AM.
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I would agree that set up properly you definitely shouldn't feel higher up on one bike then the other. There should be room to adjust saddle height and handlebar height on both sizes to be exactly the same. The reach and top tube length is the main thing that would be different. You should also ride each bike in a 52 and 54 so you can compare apples to apples. But I am 5'10.5 and ride between a 54 and 56 depending on the bike so I would think the 54 is probably too big for you
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If you can sit comfortably in that position as Machka says then your golden.
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This may be an open ended question but how do you know if a bike fits? I rode 54cm and 52cm Treks and could not really tell a significant difference besides the fact that I felt slightly higher up on the 54cm. On the 54cm, standing with the top tube between my legs, I had just mm's of space but it still felt OK. The 52cm felt OK also but I felt like I was riding a kids bike. I dunno maybe it was my inexperience or psychological.
Note the 54cm Trek (Madone 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
Note the 54cm Trek (Madone 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
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I'm not sure about the Trek 1.2 but the Madone is considered a race geometry bike FYI. The Domane is Trek's endurance bike.
Whatever, that doesn't really matter.
Im 5' 5", no idea what my inseam is. I have a Trek Madone H2 geometry, 52 cm. Love that bike, it fits me well.
Whatever, that doesn't really matter.
Im 5' 5", no idea what my inseam is. I have a Trek Madone H2 geometry, 52 cm. Love that bike, it fits me well.
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Also, a bike can feel good for a ten minute ride, but after an hour or several hours it might not be working well at all for you. Going beyond the basics, and finding a finely tuned good fit, or an excellent fit, can be more detailed.
Last edited by lightspree; 04-22-16 at 11:34 PM.
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This may be an open ended question but how do you know if a bike fits? I rode 54cm and 52cm Treks and could not really tell a significant difference besides the fact that I felt slightly higher up on the 54cm. On the 54cm, standing with the top tube between my legs, I had just mm's of space but it still felt OK. The 52cm felt OK also but I felt like I was riding a kids bike. I dunno maybe it was my inexperience or psychological.
Note the 54cm Trek (Madone 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
Note the 54cm Trek (Madone 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
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This may be an open ended question but how do you know if a bike fits? I rode 54cm and 52cm Treks and could not really tell a significant difference besides the fact that I felt slightly higher up on the 54cm. On the 54cm, standing with the top tube between my legs, I had just mm's of space but it still felt OK. The 52cm felt OK also but I felt like I was riding a kids bike. I dunno maybe it was my inexperience or psychological.
Note the 54cm Trek (Madone 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
Note the 54cm Trek (Madone 2.3) was endurance and the 52cm was more of a race oriented (Trek 1.2). I am interested in the endurance geometry.
The associate at the LBS felt that the 52cm fit me best and that my leg angle looked better. He stated that on the 54cm the handlebar is a tad wider also. i did feel like my arms were slightly wider apart. On the 52cm my arms felt straighter.
I can say that sitting on a road bike felt strange after riding hybrid all these years. i am 5'5" to 5'6" with 34 waist and 30 inseam.
I'm not convinced that the bike shop employee that you spoke to entirely knows what he/she is doing...
Leg angles can be adjusted by moving the saddle fore and aft, as well as up and down. Fitting should start with the basics, knee cap just forward of pedal axle at 3 o'clock with the ball of the foot over the pedal axle. Saddle should be adjusted so that the leg is just short of fully straight, and not locked. There are a range of saddle positions that will fit this criteria. The idea is to get a bike that fit you at the basic position, and then tweek the saddle, handlebar stem and handlebars over time to get the perfect fit.
You should not be riding different models to compare different models. That's not really going to tell you anything. As someone else already mentioned, you need to test ride both models in both sizes, properly adjusted for you to take an accurate idea of how of the characteristics of that bike model, or that size of bike model.
From the sounds of it, you have longer than average legs for your torso length. If you get a bike that fits your legs, you're going to find that the top tube is on the long side. Modern, sloping top tube bikes may not fit you correctly. They fit people with shorter than average legs and longer torsos. You might consider trying some Women's models. True Women's bikes (that are not just cosmetic altered for marketing) are built with shorter top tubes with the same length seat tubes as Men's models. I believe that this may fit you better than some Men's bikes. If you fit a 54 Men's bike, seat tube/standover wise, but feel like you're too stretched out, a Women's 54 has a shorter top tube, so the standover will be the same, but the reach to the handlebars will be slightly shorter.
Last edited by RoadGuy; 04-23-16 at 12:16 AM.
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+1
I prefer smaller frame sizes, properly adjusted. And I find that 100% of the many bike shops I've been in put me on a larger bike than what is optimal for me.
I am significantly taller than the OP, and I prefer 50cm over 52cm in most bikes.
I prefer smaller frame sizes, properly adjusted. And I find that 100% of the many bike shops I've been in put me on a larger bike than what is optimal for me.
I am significantly taller than the OP, and I prefer 50cm over 52cm in most bikes.
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K.O.P.S. or Knee Over Pedal Spindle is a widely spread belief, as pointed out in the editor's note to the article at sheldonbrown.com:
"Exploding myths is tough work."
And doesn't happen overnight, especially if it is well established and entrenched.
"Exploding myths is tough work."
And doesn't happen overnight, especially if it is well established and entrenched.
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From the sounds of it, you have longer than average legs for your torso length. If you get a bike that fits your legs, you're going to find that the top tube is on the long side. Modern, sloping top tube bikes may not fit you correctly. They fit people with shorter than average legs and longer torsos. You might consider trying some Women's models. True Women's bikes (that are not just cosmetic altered for marketing) are built with shorter top tubes with the same length seat tubes as Men's models. I believe that this may fit you better than some Men's bikes. If you fit a 54 Men's bike, seat tube/standover wise, but feel like you're too stretched out, a Women's 54 has a shorter top tube, so the standover will be the same, but the reach to the handlebars will be slightly shorter.
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I'm starting to seriously believe that it is something supernatural.
My first bike fit fairly well when I first got it, and over some time, as I got more used to riding, we adjusted the fit and made some improvements. The fitter was very experienced and very attentive, but when I wanted to get a made-to-measure steel frame, he sent me to a shop that had a contraption for making all kinds of adjustments to get some kind of ideal frame geometry. When the bike came together, I was quite pleased with the fit, but again, I was continuing to get more comfortable riding a bit more aggressively, so we made some slight adjustments and everything is fine.
While the steel bike continues to be as comfy as ever, as I continued to race on the first bike, I got to feeling it was slightly cramped, and since it already had the saddle pushed all the way back and a 110 mm stem, I got the sense the fit was "compromised," and decided to get a new bike to race on and expected to get the next size up. Well, although they are different models, it turns out the bike that fit was the same nominal size. But after the initial setup, I was truly amazed by how perfectly the bike fit. It's hard to describe, but it was in a way symmetrical with me. After a short but varied ride (steep climb and descent, flat sprint, lazy loop around the 'hood, a bit of slaloming on a little chicane) the first word that came to mind was "square." However I wanted to ride - hammer, spin, sit or stand - and the transitions between them, there was no "adjustment," rather everything just fell into place, like magic. I felt like the luckiest rider ever.
The difference in the feel of a bike that fits perfectly and one that merely fits decently is immense, but the measurable differences are so varied and fine, I'd go nuts trying to define them.
My first bike fit fairly well when I first got it, and over some time, as I got more used to riding, we adjusted the fit and made some improvements. The fitter was very experienced and very attentive, but when I wanted to get a made-to-measure steel frame, he sent me to a shop that had a contraption for making all kinds of adjustments to get some kind of ideal frame geometry. When the bike came together, I was quite pleased with the fit, but again, I was continuing to get more comfortable riding a bit more aggressively, so we made some slight adjustments and everything is fine.
While the steel bike continues to be as comfy as ever, as I continued to race on the first bike, I got to feeling it was slightly cramped, and since it already had the saddle pushed all the way back and a 110 mm stem, I got the sense the fit was "compromised," and decided to get a new bike to race on and expected to get the next size up. Well, although they are different models, it turns out the bike that fit was the same nominal size. But after the initial setup, I was truly amazed by how perfectly the bike fit. It's hard to describe, but it was in a way symmetrical with me. After a short but varied ride (steep climb and descent, flat sprint, lazy loop around the 'hood, a bit of slaloming on a little chicane) the first word that came to mind was "square." However I wanted to ride - hammer, spin, sit or stand - and the transitions between them, there was no "adjustment," rather everything just fell into place, like magic. I felt like the luckiest rider ever.
The difference in the feel of a bike that fits perfectly and one that merely fits decently is immense, but the measurable differences are so varied and fine, I'd go nuts trying to define them.
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While whst you say is correct, there is no more appropriate starting point than KOPS. It is easy to go from there.
#18
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I'm not sure about the Trek 1.2 but the Madone is considered a race geometry bike FYI. The Domane is Trek's endurance bike.
Whatever, that doesn't really matter.
Im 5' 5", no idea what my inseam is. I have a Trek Madone H2 geometry, 52 cm. Love that bike, it fits me well.
Whatever, that doesn't really matter.
Im 5' 5", no idea what my inseam is. I have a Trek Madone H2 geometry, 52 cm. Love that bike, it fits me well.
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1. If you're comfortable.
2. You ride like the wind, effortlessly.
3. And you don't hurt the next day or get injured.
There is no exact science. When you get it right, you will know.
2. You ride like the wind, effortlessly.
3. And you don't hurt the next day or get injured.
There is no exact science. When you get it right, you will know.
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Fine, but any formula is just an average starting point. Tweaks from there are expected.
#22
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Since I have limited experience in bike fitting, is it safe to rely on the knowledge of the people at the LBS? Although, when selecting the hybrid...it was a piece of cake. 17.5" Trek 7.4 fits great!
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I guess the most direct answer would be, No, it probably isn't safe, if by safe you mean coming out with a great fit from a random LBS. An okay fit -- yes, that's pretty safe.
#24
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Not necessarily; I'm a shade under 5'6", and I fit perfectly on my 50cm Pelican, 52cm Secteur, and 53cm Sojourn. They're all more than comfortable on 75mile+ rides. Geometry can have a large impact on the appropriate size range.
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#25
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As other people have said, you will know when the bike fits. I am confident that the 52cm will be OK. How varied is the geometry between manufacturers for say endurance type of bikes?