There is a lot of talk about the quality and durability of components and the quality an durability of the different components need to be put into context. For example, I have an original Acera drivetrain and rigid fork on a 1998 Univega Zig Zag. It easily has thousands of miles on it ranging from road commute to beginner to advanced trails. To say it is poor/fair not durable, is only to say it is poor/fair not durable compared to the higher level components - not poor/fair for a specific use case.
The below is a modified version of Lucin999s fantastic post:
As a comparison the ranking for component levels generally goes like this (from least expensive to more expensive):
SIS/Tourney/No name at all (least expensive possible) - Recreational use to ride around the neighborhood with your kids.
Altus - Ride on the road or on paved trails fairly often
Acera - Recreational trail riding commuter/hybrid on a regular basis
Alivio - Recreational trail riding and beginner/intermediate trails on a regular basis
Deore/Deore Shadow - Beginner-advanced trail riding on a regular basis
LX/SLX - Race ready
XT - Lighter than SLX - race ready and great durability
XTR - Lighter than XT - there are two versions for durability's sake - trail and race. Race version is ultra light weight and shows wear after a season or two of a racing. Very expensive to replace parts.
The further up the ladder you go, you are paying for the reduced weight through higher quality and lighter weight materials and higher precision manufacturing.
SRAM follows the same basic principles with a number system with XX being the highest.
In general, Shimano Deore or SRAM X5 are considered the lower threshold for "decent quality" components for frequent intermediate to advanced trail use and will shift faster and smoother in continuously changing terrain better than lower level ones.
As to the forks on these bikes, as of 2012, the RST Omega and Saturn and Suntour XCR, XCM and XCT forks which come on the majority of bikes under $700 are designed for recreational trail use (smooth dirt trails, well groomed single track, gravel roads, paved trails) and are fine for use on beginner level single track. They will make it through just fine.
The next level up from the entry level Suntour forks is their line of XC designed forks, The Axion, Epicon, and Raidon. RST also has a very capable line of forks for XC use. Rock Shox is a brand owned by SRAM and they also have recreational trail use coil shocks along with a line of high end XC and beyond as well. Rock Shox is considered a premium brand along with FOX, Marzzochi and a few others because they typically do not have supply agreements with the under $700 new bike price point and thus do not have a negative reputation Suntour and RST have picked up as a result of supplying coil shocks to the popular manufacturers.
Keep in mind, you can ride any trail with any of the drivetrains or forks mentioned above - you will likely not be able to ride as fast with the recreational trail use equipment as you would with professional race circuit designed equipment, but you can make it. Just ask the guys who are likely riding your same trails on rigid single speed bikes
If you plan to buy a bike for recreational trail use, buy equipment designed for recreational trail use or higher. If you are planning on riding intermediate or advanced trails for more than 500 miles a year, you'll be well suited to go with Shimano Deore or SRAM X5 and an air shock with rebound adjustability or better components if you can afford to do so. If your budget doesn't allow you to buy a more expensive bike, you will be best off sticking to training on the beginner trails and on the road/paved trails until you can afford to upgrade the components or the entire bicycle designed for the types of trails and riding you'd like to do.
Higher end suspension forks are marginally faster, enables a higher level of control at higher speeds and marginally more comfortable depending on how the spring rate is adjusted.
If none of these things are standing in your way of having a good time, then you are not a good candidate for anything beyond a coil fork designed for recreational trail use.
If you weigh more than 175 lbs, it is unlikely you will get full benefit of a stock coil fork as it is unlikely it is set up properly for you. I will also say most people who replace recreational trail use forks were unhappy with them because they did not have them set up properly or were using them in a way in which the fork was not designed. These forks are designed for low grade climbs and descents and well groomed single track, or, to put it another way, beginner to intermediate XC trails.
RTR forks come with a spring inside that is sent from the manufacturer. That spring was spec'd based on an average person's weight. If your weight is above average, it is likely that when you sit on your bike, the spring compresses a certain amount beyond what it was designed to compress during static use, or "sag rate." If you are heavier, it compresses beyond the ideal "sag" rate.
Some coil forks have a "preload adjustment" to compensate by compressing the spring to reduce the sag distance, but it can only compensate so much before you are completely compressing that spring during normal use. This will reduce your effective travel from 100mm to something less. The best and only way to fix this is to get a new, different, coil with a higher "spring rate." If you weigh less than 130, you probably would benefit from a softer spring.
The higher end shocks use air pressure to set the "Spring Rate." It gives you the ability to be much more precise when setting your sag rate. Some people like to adjust their sag rate based on the terrain to give them a firm ride whereas others like a plush, soft ride. You should always have a high enough spring rate so as not to bottom out during normal riding conditions.
High end suspension also gives you the ability to adjust how quickly your wheel "bounces back" after it is compressed. This is where the recreational trail use designed, entry level, forks get the bad reputation for being "Pogo Sticks of Death." With many of the entry level coil forks, if you are traveling at a high rate of speed down a very bumpy slope, your front wheel starts to act sort of like a car tire being rolled down a bumpy hill if you've ever seen that happen. The coil energy gets translated into, to use a scientific term, a boing-boing-boing effect.
This can be and should be avoided by, again, using a scientific term, slowing the F down.
Now, if your goal is to go faster down steep slopes, then a suspension system designed to go fast down bumpy slopes should be retrofitted to your bike or you should buy a bike designed to go fast down bumpy slopes.
If you upgrade your fork, it is VERY important that the distance between the ground and the bottom of your head tube not change unless this is something you desire. The longer the fork travel, the more it will ride like a "chopper" motorcycle - slowing response, making it more stable going down hill. Some higher end forks allow you to adjust the "travel" in the fork, which is the total distance the fork can compress. Some do it with spacers and some do it with a dial.
Some forks have lock out features. Some even have "remote lock out" features. This gives you a switch to hit so you can make the fork completely stiff, which is an advantage when climbing.
An advantage of a higher end fork is reduced weight compared to an entry-level fork. A highend fork usually weighs more than 30% less than an entry level fork. A lighter bike translates into less effort expended during climbs. Now, you will have to spend some bank to get there, but these usually come with a lockout that has a blow off valve to protect the fork if you forget to unlock it and hit a big bump, the ability to set your spring rate, and rebound rate and some with other adjustments that are more like fine tuning those two adjustments.
For most beginners, they can tell a difference, but don't know why it is a big difference other than they feel like they have more control at higher speeds - which they do. But you've got to ask yourself, how and why is that important to my enjoyment of this activity?
I recently bought a 26 inch bike, but have my own reasons why I chose to stick with 26 inch wheels over 29 or 650b. The more I read about 650b, the more sense it makes. The more I read about 29er, the more it makes sense. The more I read about sticking to 26 inch, the more sense it makes. There is a lot of heated discussion about wheel size right now. It really boils down to choice for you. There are a lot of people saying 650b is just a bunch of hype so the bike companies can sell more stuff. There may be some truth to that, buy the reason so many people are playing the "hype card" is because so many companies have tried to force consumers to buy something that they thought the consumer wanted.
A good case study is New Coke. Here's a company that had a tried and true product until its own diet drink began to erode market share of the global leader in soft drinks. The pie chart showed Pepsi catching up in market share compared to what was then just referred to as Coke. The execs were in a panic, "people prefer a sweeter drink, have you seen the taste tests? We've got to change the formula to make it taste more like Pepsi and Diet Coke! Holy shiz, we're going to lose our jobs - somebody DO something!"
So they created a product that tasted more like Diet Coke and Pepsi. It won taste tests hands down. It was concluded by everyone in charge that it was a superior product to the current product. And then they launched New Coke.
I think we all know what happened. But why? What the marketing execs didn't take into account was what they learned in the post mortem: people didn't care what it tasted like because it didn't taste like what they grew up drinking. Coca Cola would do taste tests and people would pick the New Coke and then when they found out, the execs would say, "See, you prefer New Coke - you should buy New Coke!" The consumers would say, "I don't care about your taste test, I'm not buying that crap. Please give me back my Coke."
Coca Cola forgot that they spent billions of dollars for decades drilling into people's heads that "Coke is Life." The remaining Coke consumers who hadn't switched to Diet or Pepsi would rather consume an inferior product because of the nostalgia. This is completely irrational.
And I believe that is what we have here. You have a bunch rational of people who ride in a certain way and recognize that one wheel size is better for them in their situation and you have a bunch of people saying, "I don't care that I picked a different wheel size in a double blind taste test, give me my 26 inch wheels back."
I think the important thing for everyone to recognize is that eventually Coke realized that extreme customization is the key to the future. You may have used one of their new fangled soda dispensers recently. If you don't know what I'm talking about, Coke has a touch screen that lets you "customize your drinking experience." You can have Coke, Sprite, whatever. Oh, you want a shot of grape in that? Here you go! You want to put some cherry in that too? Fine, knock yourself out.
For these brands (and I use that term instead of manufacturer because, for the most part, they are not doing any actual manufacturing) to say that they are predicting they will be forced to limit consumer choice by eliminating the 26 inch wheel from their lineup is simply absurd. If these brands had a progressive thinker in their marketing departments, they'd be figuring out a way to deliver a bike to your doorstep with any option you want for less money than the old school guys are able to do it. You want a custom geometry carbon frame? Here you go! You want 650b in the front and 24 inch in the back? That's pretty weird, but I'm sure it's going to be awesome for you. You want tubeless Racing Ralphs on that? Knock yourself out.
There will forever be completely bonkers irrational consumers who choose to purchase products for reasons even they can't explain. The reality is, it doesn't matter. Buy a bike, ride it, smile. Don't buy something because you think you're missing out on something. Only buy something when you know the reason you want to buy it, regardless of what that reason is.
Most bikes that come with pedals come with "test ride pedals." They are cheapo plastic or, in some cases, they are inexpensive alloy pedals. The high end bikes come with no pedals.
There are a lot of reasons why people choose to switch stock pedals. If you're having trouble with your feet slipping off your stock pedals, it may be the shoes you are wearing. If you're new to the sport, there is only one brand I recommend for wearing with flat pedals: 5.10s. This company was founded by developing climbing shoes with the highest friction and lightest weight rubber in the world. They make several styles specific for MTB, but any of their shoes with Stealth rubber soles will be better than running shoes. If you still want to buy new pedals for aesthetics, or performance, Pricepoint.com has shoe/pedal combo deals for a good price. For a beginner, you can't go wrong with any of the flat pedal/5.10 shoe combos.
There is a lot of debate as to when someone should go with clip less pedals or stick with flats. Again, you have to ask yourself, how will my experience be different if I get a new set of pedals and shoes? Why am I considering new pedals?
There are two main reasons: weight and traction. You want a lightweight shoe with a stiff sole and lightweight pedals that keep your energy transferred to the rear wheel. Like all decisions regarding equipment, there are trade offs and you'll have to come to your own conclusions and decisions which pedals are right for you.
Before you decide, here is some science that aims to debunk the clipless dogma: http://www.bikejames.com/strength/speci ... al-stroke/