rangun

Hey everyone!
I'm a 19 year old guy and thinking of buying a new bike, as my old one is really destroyed. I'd use the bike to ride on trail bycicle paths, 'cause I love nature and taking pictures of it, so the bike is good to reach those places.
Because of this, I would use my bike mainly in nature, e.g. fields, mountain paths or forests/woods. I know that in this case MTB should be the only option, but here's the deal: I'm 5'7" (171cm), so not really the tallest guy who has everly walked on earth another thing is, that I prefer small bikes, as I tend to have problems controlling a big MTB.
Now what would you recommend on buying? A 26" MTB or a 20" BMX? Are BMX really that bad for nature paths / trials?
Or maybe a 20" MTB, if they exists? But I'm afraid that while 20" BMX look rather cool, a 20" MTB just looks childish. Don't know, though. Help

JonathanGennick 

BMX doesn't make sense if you're going for distance and trying to get places. Buy a 26" bike.

Also: Go to a bike shop and get their help in selecting a reasonable frame size. Getting sized correctly should help with the control problems.

eds49721

Most manufacturers make frames down to 12" - 14" size range.
Im 5'9" and a 17.5" frame fits me really well. Youd probably need about a 15" size which shouldnt be too hard to find.

Zephyr11

You're taller than me. I'm 5'3 and ride an XS (I think it's like a 14"). You can definitely fit on a small or medium (say 15-17"). Err on the smaller side if you like small bikes.

BMX bikes aren't ideal for trail riding. Due to their geometry, you'd have to stand constantly (even if you raise the seat, it's not a good pedaling platform). Their gearing is more suited for either BMX racing on a BMX track, dirt jumps, or park (depending on what kind you get) than trails, and it will be a singlespeed. You'd get either no brakes or a single rear U-brake (or V-brake if it's a race bike), but nothing up front (which is where most of your stopping power comes from while riding trails). Handling will be twitchy, and the small wheel size will make it harder to roll over objects. Not to mention, small BMX bikes are tough to find. At your height, you'd most likely want a 20.25 or 20.5 top tube, but most full chromoly completes tend to be on the larger side, with the smaller bikes being only partially chromoly and the rest hi-ten.

Greyryder

I ride a BMX on MTB trails all the time. It's a blast. Like you, I'm just not fond of larger bikes. The trails I ride at are tight and twisty, so the extra agility afforded by a BMX bike makes things really fun. I haven't really had a problem with just a rear brakes, but I shift my weight around when I'm riding so much that I barely even think about scooting back behind the seat, wen I need to brake on a downhill.

I'd definitely recommend a race bike over a freestyle bike. Freestyle bikes usually have shorter front ends, so it'll feel cramped. If you want front brakes, you can always put on a freestyle fork with U brake bosses, but you won't be able to run matching brake levers.

The real problem is the the vertically compact nature of most newer BMX frames. I'm also 5'7", and at almost maximum extension, I can get my seat to where I can put my feet almost flat on the ground, from the saddle. This is where I like my seat, but my frame is an older Supercross, and I think it's a little taller than newer frames. A rigid singlespeed tends to have you off the seat a lot anyway, but it's still something to consider.

I'd recommend at least a 20.5" top tube. That's what mine is, and it feels great, but my stem is longer than the 53mm most current stems max out at. Standard's 125r is available with a 20.75" top tube, but I don't think it's offered as a complete bike. (I'd love to custom order one, with an extended and gusseted seat tube.) Standard does a lot of custom work at very reasonable prices, so you could even order a fork with canti bosses, if you wanted.

The real downside to a BMX, is that if you have to do a lot of hill climbing, you're either going to have the bike geared super low, or you'll be pushing it up the hills.

Remember, BMX = bicycle moto-cross. These are off road bikes. 20" knobby tires are still plentiful. There's no reason you have to use a true mountain bike. Ride what you like, and have fun.

frankenmike 

Get a BMX bro! The climbs will be no problem with your knees hitting your chest. Seriously- BMX bikes are kid toys(okay not really, but really). There are plenty of smaller riders who ride trails on mountain bikes.

Greyryder

I wouldn't tell that to Harry Leary, or Matt Hoffman.

FCDrifter

my fiance is 4'11" and she has ridden a 29r and loved it. I vote mtb and agree with the comment of go to a bike shop and talk to them

colombo357

Definitely get the BMX.

roll out shelve

generally depends on what your thrill is. I am using a MTB mainly because I go off road and dirt roads plus, downhill is my thing. I believe MTB is a crossbreed of BMX and Motocross, making it possible to use anywhere. And is durable.