I need to decide which frame size of a mountain bike to pick: 21" frame, horisontal top tube length 60.5 cm, standover height 84.6 cm and another 23", 61.5 cm, 88.1 cm respectively; wheels are smaller size 26" on both. My height is 184 cm, inseam leg 91 cm. Currently I'm riding 21.3" (wheels 26") and I wish it was a couple of inches higher because with the saddle set to the right height (my leg is almost completely stretched with the pedal in its lowest position) the height of the handlebar is about an inch lower than the saddle. According to a cycling ergonomics book I read the handlebar should be an inch or two higher than the saddle but not more than 4 inches (otherwise back muscles are not strained and wouldnt work). So to achive that on this frame I would need to use a stem raiser (rises up to 3 1/4") which in general is not good for frame as it adds additional load onto the stem's end. In a 23" frame saddle - handlebar ratio should be perfectly right but I'm wooried about whether there would be correct weight distribution between back and front wheels (especially that the tt length is 1 cm bigger). On the other hand according to a chart 21" is enough for my height; maybe my body's proportions are not standard (legs are too long). In such a case should I err towards larger or smaller one? Please give your suggestions.
What Frame Size Should I Pick?
- Thread starter Mike1234
- Start date
FWIW. You and every other comparatively-and-or-probably newbie needs to realize that whatever your read in whomever's "cycling ergonomics book" is stating his-or-her opinion based on mostly on their own physiology and the terrain which s/he rides on ...Mike1234 said:
A flexible & aggressive rider (either Road or MTB) will probably have their handlebars lower than a casual, bike trail rider could ever feel comfortable riding regardless of the terrain ...
The writer/"expert" CLEARLY must not have OR does not take into account the stem length ...
A shorter stem has a similar effect as a higher stem might.
In other words, what you read is a starting point ...
And, you should not take it as gospel.
If you are comfortable, now, then you are good-to-go with the saddle-to-handlebar reach ...
If you are NOT comfortable, now, then you simply need to decide if you feel like you are out of control or too cramped when descending-or-climbing ...
If you are comfortable, now, then you should probably leave well enough alone until YOU actually feel a need to change your riding position ...
To state the obvious, the rider is-capable-of-and-can move fore-and-aft & laterally (shift his-or-her weight) while riding AND a rider's posture should not replicate an El Cid type of excursion on the beach.
BTW. So-called professional bike fitters bring their own prejudices & backgrounds to the task ... and, what works for them & their friends may not be suitable for many-or-most riders.
BTW2. IF you are truly looking for a new bike (instead of a shorter-or-longer stem ... at least, for the time being until YOU know what works for YOU & not someone else -- a stem-or-two will be less expensive than a new bike), then at your height you may want to consider either a 29er or a MTB with 650b wheels unless you have Flamingo-like legs OR are riding in really muddy conditions.
Who says the handlebar has to be an inch or two higher than the saddle?
Most people who write these bicycle "style guides" are writing about their own preferences, riders who share similar body proportions, or riders with average body proportions, whatever that may be.
I'm looking at your overall height, which suggests the 21" is just about right, and your leg length, which is very close to 50 percent of your overall height. That's long. That means you have a relatively short torso, which means the 23" will likely be too much of a reach.
I suggest you look at your arms. If they are proportional to your legs, it means that reaching down a few more centimeters is not that much of stretch. If they are more proportional to your torso (short, that is) you might need a riser stem, or a shorter stem.
Remember that any significant rise in handlebar height will likely necessitate longer shift cables and brake lines or cables.
Most people who write these bicycle "style guides" are writing about their own preferences, riders who share similar body proportions, or riders with average body proportions, whatever that may be.
I'm looking at your overall height, which suggests the 21" is just about right, and your leg length, which is very close to 50 percent of your overall height. That's long. That means you have a relatively short torso, which means the 23" will likely be too much of a reach.
I suggest you look at your arms. If they are proportional to your legs, it means that reaching down a few more centimeters is not that much of stretch. If they are more proportional to your torso (short, that is) you might need a riser stem, or a shorter stem.
Remember that any significant rise in handlebar height will likely necessitate longer shift cables and brake lines or cables.
There are those who will say there is mountain biking and there is mountain biking. I think it all boils down to the type of mountain biking you will be doing and how aggressive you are going to be. The key element is that you are comfortable when riding and that you can do all that you will need to do when you are on the bike.
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