MTB Commuter Sizing?
#1
My pants used to fit me
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MTB Commuter Sizing?
I'm thinking about buying an old rigid MTB to fit with slicks and fenders for commuting. It was always my understanding that you go with way more standover on a MTB than a roadie to give your crotch more space when bouncing around offroad. This bike will never see dirt.
I ride a 16" MTB and a 49cm road bike. Do I go with a 16" for the commuter or would I want to go bigger?
I ride a 16" MTB and a 49cm road bike. Do I go with a 16" for the commuter or would I want to go bigger?
#2
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Go with the reach. Stay with a small or a 15 or a 16 or whatever it is for you. MTB's do have more standover, it's true. That's still convenient with a commuter bike, it gives you something like stepthrough when you have panniers or a kid seat.
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#3
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MTB sizing by seat tube length is extremely variable, as the top tube can slope down by so many different angles. Reach will be more important for you, and you'll just have to test-ride. But yes, for a MTB that you plan to never take off road, I would tend to size it up in the seattube some, as long as it doesn't put the bars out of reach.
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FWIW & this might be useless info, I found my 1st MTB (red). thought it was a blast. did some mods & got a really fast commute time out of it. one day at my LBS was told it was too small 18" & told to find a 20" which I did (same brand & model) (grey). I don't think I remember noticing much difference in "fit"
Last edited by rumrunn6; 02-20-18 at 01:08 PM.
#5
Pokemon Master
I ride a 19" modern MTB off road. For a flat bar bike I like a 59-61cm center of seat tube to center of head tube top tube length. On my vintage Mongoose, that means I can ride up to the 23" frame. I also have a 23.5 High Sierra that fits the bill. My 88 or 89 RockHopper is a 20" frame, but apparently has a longer top tube as all 3 measure the same.
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MTB sizing by seat tube length is extremely variable, as the top tube can slope down by so many different angles. Reach will be more important for you, and you'll just have to test-ride. But yes, for a MTB that you plan to never take off road, I would tend to size it up in the seattube some, as long as it doesn't put the bars out of reach.
A 19” road bike is 49cm, by the way but the proportions are very different.
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#7
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I have two mtb at home that are labeled as 20" (with a sticker on the seat tube), but different top tube angles and lengths make them vastly different size bikes.
#8
My pants used to fit me
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Sounds like the most important thing is to look for something with an effective TT length of 20.8" like my current road commuter (and ride before buying if possible).
Thanks!
Thanks!
#9
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Yes, TT length is most important, effective seat tube length is easily modified by the extendible seat post.
#10
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On the other hand, I have five 20" mountain bikes that aren't "vastly" different in the way that I fit on them. That's from a cruiser type mountain bike to two dual suspension bikes.
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Plan Epsilon Around Lake Michigan in the era of Covid
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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!
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#12
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I would say that one of them is marked in error then. I've owned 22 mountain bikes (including the 5 I have now). I haven't ridden any mountain bike is has a 20" frame that is too small nor, for that matter, is too big. Granted I don't have any with wheels larger than 26". 29er could mess up the sizing but for someone who rides a 16" frame, a 29er probably isn't a good idea to begin with.
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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!
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!