Mountain Biking - BMX Vs Mountain Bike

what the difference between these two bikes? pretty similar in the eye of a newcomer.

the biggest differance is that BMX bikes have 20" wheels vs MTBs have 26" wheels and gearing

Frame style and size as well, handlebar setup, i dunno about bmx bikes nowadays, but do they have shocks on em now? As far as i know most are shockless.

I think there are some insanely tallented BMX riders out there. It's too bad they're stereotyped as punk kids with nothing better to do than break ****. Some BMX riders can ride some insanely technical stuff and pull some major tricks, all without suspension or wide tires.

Gonzo,

There are BMX suspension forks on the market and I believe a couple of bmx suspension frames. Neither of which sell well :D

Jim,

I agree 100%. Any mtb that is worried about going a little big should go watch these guys rip. Mtbers will never be afraid of 5 ft drops again. The main differences are size and weight. BMX geometry is different as well allowing for more tricks than just riding. BMX also tend to weigh more than the average bike (except freeride and dh) :)

MTBs have wide range and low ratio gearing. BMX are low ratio singlespeeds.

In the UK, one of our top roadie/track racers is also a BMX champion

[QUOTE]BMX also tend to weigh more than the average bike (except freeride and dh)


BMX Bikes are very light.

Just like road bikes or mtn bikes, there are many genre's of BMX bikes.

Dirt Jumpers, are super beefy and heavy, usually only a rear brake and built to handle serious abuse.

Freestyle and Flatland bikes are also heavy with 48 spoke wheels, axle pegs...etc. Geometries are different than a DJ bike.

BMX race bikes, are built light and nimble.

The two most common materials for BMX bikes are Chromoly Steel and Aluminum. Chromo bikes are much heavier and chromo is the choice for a frame that is designed for some serious abuse.

Aluminum is becoming more popular, even for some DJ bikes with the addition of huge gussets welded at critical areas. For lighter weight BMX race bikes, they are predominantly Aluminum, and now a trend towards Titanium (high modulus of elasticity and good strength to weight ratio)

Similarly, there are many genre's of mtn biking these days;
cross country (XC), Freeriding (FR), Dual Slalom (DS), Downhill (DH), Dirt Jumping (DJ) and even Singlespeed versions of these (SS).

With mtn bikes, you will see frames of Aluminum (majority), steel (chromo), Titanium, Carbon Fibre,....etc.

The big difference b/t a BMX and a Mtn bike is one, the size of wheels. BMX has 20" and 24" wheels. Mtn has 26" mostly, some DJ, and DS are using 24" and a few XC folks are trying out 29" wheels.

A newer mtn bike usually has gears (usually 24 or 27 speed), and some form of suspension (front or/and rear). With a BMX bike your rider position is more upright, with mtn (XC for instance) is more stretched out. However, the FR and DH also requires a more upright postion.

O.k., getting confusing.

A BMX bike is smaller and built for shorter rides, sprint races, or tricks.

A mtn bike is designed for longer rides, climbing and descending and usually bigger!

L8R

Originally posted by djbowen1
[QUOTE]BMX also tend to weigh more than the average bike (except freeride and dh)


BMX Bikes are very light.

I do agree with a2 but most of the bmx's I see and ride at the dirt park are heavier than my freeride bike. All of them are chromoly so that usually helps the weight.

Originally posted by djbowen1

BMX also tend to weigh more than the average bike (except freeride and dh)


BMX Bikes are very light. None of the BMX bikes that come into my shop are what I would consider light. In fact I haven't come across one that was lighter than my 30 lb hardtail commuter bike.

My haro Monocoque BMX bike is 23 pounds and thats fairly light for a bmx bike. I used it for racing and some DJ/trail use. but some more "race specific" BMX bikes are surely lighter than 23 pounds as i didnt use mine for only race and needed the added strength for jumping.

I'll make it really simple:

BMX Bike - Very small frame, no suspension, 20" wheels. Almost always made of steel unless used for BMX racing. No gears. Ideal weight is around 30 pounds. Used for dirt jumping and tricks.

Street/Dirt Jump MTB - Somewhat small frame, usually has front suspension only, with 3-4 inches of travel. Usually 24" wheels. Sometimes has gears (not always), but usually no more than 18, often just 9. Used for riding very similar to BMX, but with bigger jumps. Ideal weight is around 35+ pounds. Often made of steel.

Freeride MTB - Still has a small frame, maybe a bit bigger than a Street MTB. The main difference is it has more suspension. Freeride MTBs can have front and rear suspension, although many have front only. Anywhere from 5-9 inches of travel. Usually has a 24" rear wheel and 26" front wheel. Almost always has 18 gears. Used for riding "North Shore" style trails with stunts and very technical obsticles. Also used for doing huge jumps and drops. Freeride bikes are also used for recreational downhill, but are not suited to racing. Can be made of steel or aluminum - ideal weight is about 38 pounds for a hardtail or 40-50 pounds for a full-suspension. .

Downhill (racing) MTB - Like a freeride MTB, but a larger frame that has a more stretched-out riding position. Usually has 26" wheels on the front and back. Travel is usually 7-10 inches, just a bit more than a freeride bike. Almost all downhill bikes have rear suspension in addition to front. Most of the time has just 9 gears. Used for downhill racing. Usually made of aluminum - ideal weight is around 40-45 pounds.

And finally....

Cross Country/Traditional Mountain Bike - large frame, 26" front and back wheels, 4 or so inches of travel. Some cross-country bikes now have 29" wheels that let them roll over things more easily and go faster. Almost always has 27 gears. Used for riding and racing on trails through the woods. These bikes are made of aluminum, titanium or carbon. Ideal weight is about 25 pounds.