how does one properly size a bike
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how does one properly size a bike
I heard there were different methods for road bikes vs. mountain bikes. I want to buy a used bike from craigslist or ebay, and since most bikes tend to get sold very quickly from those places I dont think I have time to mess around. I'd like to know right off the bat before I even drive to the person's place if the bike will fit me. Anybody have any tips?
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I heard there were different methods for road bikes vs. mountain bikes. I want to buy a used bike from craigslist or ebay, and since most bikes tend to get sold very quickly from those places I dont think I have time to mess around. I'd like to know right off the bat before I even drive to the person's place if the bike will fit me. Anybody have any tips?
Once you get a size range that fits, it's pretty standard. You could go to a shop and see what fits but that would be kinda rude...I mean you aren't planning on buy from them. Check your buddy's bikes. If you have a friend about your size, you should ride a similar sized frame.
The 'almost' bit? Get up on the pedals and see if the top tube is too long or too short. If you feel like you should be ringing bells in Paris, it's too short. If you feel like a giraffe drinking water, it's too long. Adjustments can be made in the stem length and the saddle position but only a few inches. Thankfully, most bikes fall into similar ranges for similar sized frames.
And ride it. If it doesn't feel right...it ain't!
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Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
#4
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Nope, they're kind of like shoes in that respect. You can get a rough idea with the numbers but until you try them on you won't know if they fit comfortably.
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I'm no expert on MTB fitting myself, but one odd thing I have noticed, is that if one looks at the riders' size and the bikes they ride from sites like CyclingNews.com, I notice most pros seem to ride bigger bikes in terms of top tube lengths than what you might see on road bikes for the same riders. Example: Chris Eatough's Trek Top Fuel: rider 5'10" on a 62.8cm top tube. Is this normal? Same size guy on road bike would be on like a 55 to 57 likely. Not even close to a 62!
In my case my road bike is a 57cm top tube and my Titus Racer X is actually very close to that (measured 'virtual' or level). It feels fine to me. I run a 120mm stem though.
In my case my road bike is a 57cm top tube and my Titus Racer X is actually very close to that (measured 'virtual' or level). It feels fine to me. I run a 120mm stem though.
Last edited by gfrance; 07-09-08 at 09:49 AM.
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There are formulas and tables all over the place. https://www.google.com/search?hl=en&q=bike+sizing
Be aware of a fundamental difference between road bikes and mountain bikes, though. Mountain bikes have sloping top tubes, while road bikes have level or nearly level top tubes. This means that for the same effective size, the mountain bike will have smaller stated size because it has a shorter seat tube (the usual basis of measurement for the stated size).
Be aware of a fundamental difference between road bikes and mountain bikes, though. Mountain bikes have sloping top tubes, while road bikes have level or nearly level top tubes. This means that for the same effective size, the mountain bike will have smaller stated size because it has a shorter seat tube (the usual basis of measurement for the stated size).