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Understanding
the Components
When
designing a custom ride you will need to consider these features
when deciding which frame you are going to build your bike around,
or even if it is an off the rack unit, you will still need to take
all these into consideration. We have listed the component in order
of importance of selection but not necessarily in the order of
importance when it comes to maintenance
and repair.
Frames
All
bikes need a good frame however the mountain bike frame must be
exceedingly strong in order to survive all of
those rocks and logs that you will ride over. As you have probably noticed,
the standard frame above
is a diamond shape made from two triangle forms. The triangle is the strongest form known to man but
recent developments in design and strength have allowed the
manufacturers to
create sub frames that allow the rear wheel to travel in an up/down
motion, as below
 .
These are shock dampened and provide a smoother
ride.
1. Frame Features -
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Weight and Stiffness
It is difficult to produce a lightweight frame
that is also stiff because stiffness is achieved by using thicker tubes
which add weight. Stiffness is important because it
allows the rider's energy to be converted into moving the bike forward
without wasting energy in a flexing frame. The lightest frames are generally made of
titanium which is very expensive. If you want a stiff, but
lightweight bike, expect a high price ticket!
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2. Joining Methods -
TIG Welding (tungsten inert gas)
This is the most common method for joining various parts of the frame
together. The welding is all done in an inert gas atmosphere as a measure to
prevent impurities from affecting the weld.
Brazing
Generally used on custom bikes with steel frames. T. The end
result is a strong joint with a smooth junction of tubes.
Bonding
These tubes are generally made of carbon which cannot be welded. This is a
very tedious process because the tubes are glued into lugs and
the frame is then "baked" for several hours at a very low temperature. The end
process is a very strong and lightweight frame which is generally used for racing.
3. Frame Material -
Aluminum
Commonly used to make stiff frames, aluminum is becoming more and more
popular as technology and alloys advance. Aluminum frames are fairly cheap
compared to their more high-tech cousins.
Carbon Fiber
This could be considered the best frame material
available. Carbon Fiber is very stiff and strong, but also lightweight.
Metal Matrix
Mostly made up of alloys of aluminum and ceramic particles, these
metals have a very high strength-to-weight ratio.
Steel
This is the most common material used to construct mountain bike frames
out of. It is fairly cheap, but very strong.
Titanium
A frame constructed of titanium is very light and strong, but also very
expensive because of the special welding required. Many experts report
that titanium has almost infinite life span.
Drivetrain
The drivetrain is what takes the energy from your legs and transforms it
into power that propels the bike forward using a series of gears. Bikes require two shifters: one to move the chain back and
forth on the chain rings on the frame and the other to move the chain on the
sprockets on the rear wheel.
Most shifters have index gearing (a positive click into position) which allows you to shift to
desired gear without having to look at what is happening.
Selectors -
STI Shifter or
"Rapid Fire"
These shifters are mounted underneath the handlebars and have two levers.
One located in the back to shift up using your thumb and the other located
in the front to shift down by using your index finger. This type is not
indexed and is activated and returned to a neutral
position for each gear
change. Preferred when riding in difficult terrain.
Grip Shift
These are becoming increasingly popular and are actually a part of the
handle grip which you rotate to shift up or down. These
have been around for many years but only became popular when the
Shimano factory (Shimano provides parts for may
different bike manufacturers) was damaged by an earthquake
and the bike manufacturers had to resort to using what was
available, which were the twist shift from an alternate
supplier. Resulting from this, they became mainstream equipment
and even Shimano began making them once they got up and running
again. While these are found on all multi geared type of bikes,
many mountain biker do not like this method because of the
intense jerking motion in the handlebars in difficult riding,
which can unintentionally change the gearing ratio.
Thumb Shifter
These are the push-pull shifters that appeared on the multi sprocketed bikes and
are still available. Some person prefer these still because they
reduce the possibility of unintended shifting when raising the
front wheel or some other maneuver that requires manipulation of
the handlebars.
Chains -
This is probably the hardest worked component on your mountain bike. It
has to constantly stand up to a wide range of gear changes and at a very
rapid speed. It also has to work despite of the fact that it is covered in
mud, sand, water, grit or anything else you can manage to get on it.
Manufacturers have improved the chain to allow it to flex and withstand
these conditions.
Hyperglide Cassettes and Chains
When used with the proper components, these will give you the smoothest ride
you will ever find. The rear sprockets have slanted teeth which allow the
chain to slide from one gear to another. The only drawback is the fact that
the chain requires a replacement pin. In the event that the chain breaks, it
is very difficult to fix or replace. Shimano has introduced an improvement
on the Hyperglide chain called the Interactive Glide chain.
Crankset
The
crank set is made up of 2-3 different sized toothed rings.
These are directly connected to the crank shaft. The teeth
should be angled at the top edge to allow the chain to controllably
slip on or off when shifting. The teeth should show signs of
machining and not just a stamped item.
Derailleur
These
move the chain in out out from the frame and cause the chain to
thread on to a desired sprocket (on the wheel) or chainring.
This causes a change in gear ratio. The rear derailleur also has
a tensioner, incorporated into it's structure, to help take up
the slack that would result from a change in gears.
FYI
Gear ratio - The relationship between the
pedaling speed and
wheel rotation speed which depends on the gear selected by a chainring and
rear sprocket combination. If the chain is on the largest chainring and
smallest rear sprocket, you are in the highest gear. If the chain is on the
smallest chainring and largest rear sprocket, you are in the lowest gear .
Cadence - The rate of
pedaling, usually measured in revolutions
per minute (rpm) of one foot. A high cadence is 120 rpm and a low cadence is
60 rpm. You should aim to maintain a steady cadence. As a guide, the most
efficient cadence is 80 rpm
Gear capacity - The maximum sprocket size that a front or rear
derailleur can cope with. If a sprocket is too large, you can damage the
derailleur
See
also Pedals as your choices here will determine the way
you apply the power to the drivetrain.
Wheels
Wheels and Tires -
1. Spokes should
be properly tensioned and can be checked by using your fingers
to squeeze them 2 x2 with you finger to see if all are tensioned
equally. Some of the newer wheels or particular
applications such as BMX bikes have the spokes built into the rims to
help withstand the punishment of jumping and road hazards.
2. Rims -
Should be strong enough for the type of riding. Straddle the
bike and lock your brake and place you weight on it and then
lean sideways on it while watching for flex. If you get more
than a minimal amount of flex then this rim will not hold up for
rugged use but may be OK depending on what you plan to use
it for. Some rims are solid with no spokes and are used mostly
in racing configuration.
3. Tire Tread
- Smooth rings for Racing and touring , Knobby for mountain bikes
- a combination of the two for hybrids and BMX. See below.
4. Hubs
should have no side play but not be so tight as to prevent the
wheel from freewheeling for an acceptable amount of time when
the wheel is spun. Check for play
by rotating the axle and trying to move it from side to side.
Tires
Tires
differ depending on the type of surface they will be riding on.
Touring or racing tires that are meant to ride on hard surface
such as asphalt are narrow and have a thin ribbon tread pattern
that travels the circumference of the tire. This offers
steerability and low friction, and are generally pumped up to a
higher pressure than a off road tire. Off road
(Mountain Bike) and Hybrid (multi purpose) tend to be much wider
and are run with much lower pressure, but even at that they
differ from each other. The Mountain bike tires need to be
covered with knobby grips which will give it traction on any
surface but would be an unnecessarily rough ride on a hard road
surface. Where as on the other hand, the Hybrid are wide for
support in soft terrain and have thin ribbon treads in the
middle of the tire for hard surfaces and knobby grips
along the edges to help when off road. The hybrid may be the
best choice for someone who rides recreationally on both types
of surfaces.
Parts of a Tire
1. Inner Tubes - The inner tube determines tire pressure.
Inner tubes can be made from butyl or latex. There are two main types of
valves used on inner tubes: the Schrader valve and the Presta valve
(make
sure you have the correct valve removal tool in your
toolkit).
2. Tire Casing - There are 2 main types of tire casing:
gumwall construction which is used for cheaper mountain bikes but is
very durable and nylon casing which is light and flexible. A nylon
casing tire is determined by the amount of TPI, the greater the TPI the
better the quality of the tire.
3. Tire Size - A wide tire gives a more comfortable ride and
has better traction in wet conditions. A narrow tire will accelerate
more quickly, however it has less traction and is a less comfortable
ride.
4. Tire Tread - Smooth tires are meant for road work.
Nobbies
are for off-road riding. Multipurpose are for both road and off road
conditions. The tread patterns will vary to fit certain conditions, for
example, some offer better traction and some are better in mud.
5. Tread for front and rear -
Except for Racing bikes the front and rear wheels of
your bike do very different jobs. The back wheel requires traction and
the front needs cornering control. Tire tread on a rear tire should face
so that the tread bites into the ground, the front tire is meant to roll
easily over things like rocks or roots.
Brakes
The brakes are
one of the most important parts of your bike. Without some other
part you may not go but without brakes you may not stop when you
need to.
Brakes have evolved over the years from the old Bendix back pedal
brake to disk brakes and the caliper system that is now
prevalent in some form on most bikes today. Even with the calipers
there several choices and have seen some fantastic evolution over
the last few years.
The most popular brakes are the new V Brake that look similar
to the old side pull center pivoted, but these are pivoted on each
arm of the fork and provide much better control than the old
system that was prevalent for so many years. The old style cause
uneven pad wear and a less than acceptable performance.
Commonn
on many off the shelf bike is the older version of caliper brakes
The disk brake systems look like a miniature version of the
braking system found on motorcycles. You have a rotor and a caliper
which can be either mechanically actuated by cables or even
hydraulically. These are considered superior to other systems
but are closely rivaled by the V Brakes mentioned above.
Pedals
Parts of the pedals
Toe clips and straps - There are several ways toe clips and straps
are beneficial to a mountain biker. One is that they increase your
efficiency as you pull and push going uphill. Going downhill they keep
your feet from sliding off of the pedals and increase the control you
have over your bike.
Adjusting a toe strap:
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To tighten it, insert your foot and pull the strap upwards and
towards you.
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The toe strap will remain in position once adjusted to the correct
tension.
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Loosen the strap when you want to dismount and before going down a
hill. Do this by pressing forward on the inner edge of the buckle.
Clipless Pedals and Cleats -
Some cycling shoes will have holes drilled in
them for cleats used in clipless pedal systems. These make for a
positive contact between your foot and pedal and allows
you to not only push down on the pedal but to also lift
up on it.
Clipless systems:
Do not use this system until you are an experienced
rider and have practiced with them in a docile setting.
It take some getting used to, especially free yourself
from the clip in order to catch yourself in a fall.
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Adjustment - Make sure that the cleat
is set up in the right position in relation to your natural riding
position. Use your system's free float. It is designed to allow you
the movement of your foot's changing position while the pedal is
rotating.
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Getting on and off - To attach your shoe to the pedal press down
with the center of your foot, then press hard with your heel, to
click it in. To remove your foot, kick your ankle outwards.
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The advantage of a clipless system - They can be used in any
conditions, including mud and rain. They also give you the ability
to lift the bike over obstacles more easily and get up hills more
quickly.
Suspension
How Suspension Systems Work
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A suspension system contains a spring and a damper. The spring
supports the weight of the rider and the bike. When the bike hits a
bump the spring compresses taking the shock of the bump.
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After the bump has been absorbed, the compressed spring stretches
out again. The damper keeps the spring from bouncing back at the
rate it was compressed.
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When the spring stretches back to its original length the
suspension system is ready to absorb shock from the next bump.
Types of
Suspension Systems
Suspension Stems
(seat)-
These only offer comfort to the rider and offer no benefits to the
suspension of the bike.
Rear suspension -
Primarily
found on off road applications suchas Mountain
bikes. This provides extra comfort, control and speed.
Suspension Forks -
There are many different systems available for mountain bikes. The
main decision in choosing a suspension fork is the type of spring
damping unit used. There are 3 main damping systems: oil/air (oleos),
coiled springs, elastomer (rubber), and
elastomer/oil .(bladder).
Other
considerations
The Front End of a Bike -
Handlebars -
There is a huge variety of handlebars that one can choose from.
Each will affect your riding position differently. Mountain bike
handlebars are usually aluminum, which offers a good degree of shock
absorption. However they come in steel, chromoly, carbon-fiber and
titanium. The amount of absorption a handlebar will take depends on
the flexibility of the material.
The
handgrip portion of the handlebar may be one
of the biggest consideration when choosing
one. They generally come in 3 configurations:
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Standard
- This is the style where the grip point
back and are nearly parallel with the
direction of travel. These are comfortable
for ride of 2 hrs or less
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Under
grips -commonly used on racing bikes s
this allows the rider to keep their
profile low to cut down wind resistance.
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Upright
-These stick nearly straight up and are
built to be a good ergonomic fit as this
is the position our hand s will naturally
assume if at rest.
Perhaps
the best is a handlebar that
incorporates a combination of couple of
layouts. This enable you to change from time
to time which will keep you from becoming
fatigued. Under grips and upright
will normally have a straight grip that is
perpendicular to the direction of travel. This
will allow you to lean into the handlebar and
give your back a rest.
Grips
- The actual hand grip itself needs to
provide a good grip and absorb vibrations.
Grips can be made from foam, rubber, or gel
material. These should be replaced if they
collapse or begin to tear, as it is possible
to get blisters.
Stems
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The stem attaches the handlebars to the frame. They come in many
different styles and materials. Your riding position will be
determined by the stem's length, height and angle. You can get stems
with built-in shock absorbers, which are good for the arms and hands
on rough trails.
Headsets -
Headsets keep the fork tube and stem inside the head tube of the
bike frame. The upper and lower portions both contain ball bearings so
that the steering system runs smoothly. There are 2 types of headsets:
1) The conventional headset and 2) The Aheadset (these are lighter
than the conventional headset and are used on high-performance bikes)
Bar Ends -
Bar ends are handlebar extensions which attach to the end of the
handlebars or are fitted inside the ends. These give you the added
benefit of being able to change your riding position, necessary to
keep from getting numb during long bike rides. They also make it
easier to climb hills, as your weight is distributed through the front
end of the bike.
Saddles -
Regardless of which saddle you choose, it
must fit you. Just like some pants may suit
one person and not another the same is with
saddles. An uncomfortable saddle will spoil the
ride.
These saddles are good when riding off-road, as they allow you to
slide off the back of the saddle easily for descending.
If you spend lots of time in the saddle when you are out riding you
will want a wider saddle and a greater depth of padding.
Pricing
$$$$$$
Low
end - $89.95 - $150.00
Bikes
in this range will suffice for most people who want to
ride around town or stap it on the back of the
SUV when traveling just so they don't have try
to find parking when visiting the sites in other
cities. You can always cutomize these to be more
comfortable by changing out the saddle or grips.
Mid
range $125.00 - $600.00
Mid-range bikes are definitely the right choice if you are planning on
strictly off-road riding, but are not planning on racing. You will end up with
a high-quality bike that was relatively inexpensive because these bikes are
the middle range manufactured by different companies. The bike has some
benefits over the lower-end bikes, such as the components are usually of
higher quality and do not weigh quite as much. You will find that the
mid-range bikes are priced most competitively so you're apt to get a great
deal!
Mid-range Bikes
often Include:
24-Speeds -- Makes your ride easier and more efficient.
A
lightweight headset Stem -- The weight of the front end is greatly reduced with this
kind of headset which is a great advantage on a racing bike..
Improved
suspension
Ergonomic
handlebars
Improved
braking.
Middle to top of the range bikes
$600 - to $3000.00
Features
in addition to the midrange features:
Bonded Tubing - You will find on many of these bikes that all of the
tubing is bonded which makes it very strong.
Suspension Fork - Most high-end bikes come equipped with a suspension
fork which means that the stem is a bit lower than most.
Custom Tubing - Some companies offer the buyers choice of tubing material
used to construct their bike with. This generally tends to make the bike
lighter depending upon the material chosen.
External Butting - On high-end bikes, external butting is used to
increase the strength of the frame and also reduce the weight.
Sophisticated Fork - Some manufacturers have created their own suspension
fork which look much flashier than some of the later add-on ones most people
have.
Before you Buy -
1. We recommend that you start by reading bicycle reviews in biking
magazines or on the Internet. Also talk with friends to see what they like
and dislike about their bikes.
2. Take your prospective bike for a test drive: Make sure that the saddle
is adjusted properly and that its not above the maximum height mark. Also
make sure that you aren't stretching to reach the handlebars or are too
cramped.
3. Ensure that the wheels are secure in the forks and that the
quick-release levers are tight. Also check to see that the headset is tight,
if its not the bike will not be considered under warranty. While checking
the headset, make sure that the handlebars are correctly positioned in the
frame, Push down hard on the handlebars as well to see if anything is loose,
e.g. brake levers or shifters.
4. Don't allow a pushy salesperson to coax you into buying a bike that
you don't really know anything about.
5. Check to see that you are buying the right size.
6. Look around at other bike shops or in catalogs to see if you are
paying more for your bike than you should be.
7. If the bike is being sold at a very low price, don't hesitate to ask
the retailer why the bike is going for that price. There could be a defect
which would cause a loss of warranty.
8. If you are offered any kind of free tune up after purchasing your
bike, make sure that you bring it in. This will allow for any adjustments to
be made if the bike had not been set up properly.
9. If you feel that you don't really know
very much about bikes, bring a
friend along who knows more about them and can ask helpful questions.
Things to
Consider-
1. Try to set a budget for yourself so that you will only look at bikes
that are in your price range. This will make it easier on you to choose one
you like and feel comfortable forking the cash over for.
2. Try to assess how much riding you'll be doing and on what kinds of
terrain.
3. Do as much research on your possible purchase as you can. Collect
booklets on each bike and then compare them to see which bike has the
components you want.
4. Try to test ride each bike that you've been looking at because there's
no better comparison then actually riding.
5. If you are intending to buy a second-hand bike, ask a local bike shop
to look it over for you to make sure everything is working properly. Also,
ask the seller for the original sales receipt to prove that the bike wasn't
stolen. You should also find out what types of riding the seller used the
bike for to make sure that the bike isn't worn out.
Extras
The best thing about buying a mid-range bike is the fact that you have
money to spend on upgrading your bike. You can always find the latest
accessories that are easy to install yourself at your local bike shop. The
following accessories are relatively inexpensive, are easy to install and
will improve your ride.
Bar Ends - If you decided to purchase bar ends, they will increase
your power and control as you climb up steep hills as well as give you
plenty of hand positions for riding on roads.
Toe Clips - These are great because the straps keep the ball of your
foot centered over the pedal where you will get the most out of each
stride. They are also very helpful for things like bunny hops because
you are able to pull up on the pedals with your feet. They may take a
bit of getting use to, so practice before you hit the trails!
Tires - If you are going to upgrade one thing on your bike, this is
probably the best place to start. Mid-range bikes come with tires that
are knobby enough to get by with on trails, but the knobbier the tire
the more traction you'll have.
Saddles - Most entry-level bikes come with generic saddles. If you
purchase a new saddle you can get it customized to serve your riding
needs. Most mountain bikers prefer a narrower saddle because it allows
you to slide back easily for going down hill or trying to get better
traction.
Clipless Pedals - This is probably one of the most
expensive upgrades you'll find because you have to buy the clipless
pedals along witht eh shoes to fit. If you decided to install a pair of
clipless pedals, you won't be sorry! You have total connection witht the
pedals which means that all of your energy is focused on propelling the
bike forward and isn't lost between your foot and the pedal. They are
hard to get used to at first, but we're sure that you won't give them up
once you've figured the out!\
Fit
Finding a bike that looks like what you want is easy, but fitting it is
a completely different story. When you find a bike that fits properly, you
will feel comfortable, relaxed and ready to hit the trails. Follow the
simple adjusting steps below to make sure that you are getting the most
out of your bike!
1. Finding the right fit - When you find a bike that fits you properly,
you should have about three to four inches clearance between you and the
top tube. When the seat and handlebars are adjusted at the same height,
you should be able to sit comfortably on the bike. You will have more
control over the bike if you are relaxed because it is easier to balance
and if you are stretching too far it's more difficult to balance.
2. Adjusting the saddle height - When you first begin riding, keep the
saddle on the low-end and then raise it as you become more experienced.
Your feet should touch the pedals when your knee is straight and the pedal
is at the lowest point.
3. Adjusting the saddle position - As a rule, you should have about 2
inches adjustment on the rails of your saddle. There is no set standard to
decide when it is adjusted properly because it's personal preference. Try
adjusting the position until you find one that works well for you.
4. Adjusting the handlebars - Most stems have about 1 to 2 inches of
extra stem to adjust the height. Most people find that if the handlebars
are adjusted below the saddle then the handlebars are more comfortable to
hold on to. If you want to take the scientific approach, look at it this
way: if your arms are extended at a 45 degree angle with your arms
slightly bent then your handlebars are adjusted properly.
WARNING! Companies use different criteria when deciding on
frame size. Don't mistake one 19-inch frame for another!
Adjustments
After finding your dream bike and making all of the adjustments, it's
time to focus on parts. Keep in mind that if you aren't satisfied with
some of the components on your bike when you buy it you are able to trade
them in for others. This usually turns out to be cheaper when it comes to upgrading.
Saddle - Finding the perfect saddle is not easy and may take some
riders many tries before they find it. Here are some tips: make sure that
the saddle is narrow enough that you can easily slide off of the back,
also more padding is not always better! In some cases it will rub against
your thighs and after a long ride will become very uncomfortable!
Brake levers - Most brake levers can be adjusted with an Allen Key by
loosening or tightening the clamp to fit your needs. Here are the
following ways that they can be adjusted:
1. Up or down - You can rotate the levers up or down until they are
comfortable. You shouldn't feel any kind of pull in your arms.
2. In or out - You can move the levers closer together (towards the
center) or farther apart (towards the grips) depending on your shoulder
width.
3. Reach adjustment - You are also able to adjust the resting
position of the brake levers either closer or farther from the
handlebars. Just be forewarned that your break setup may need to be
adjusted after this.
Handlebars - Most handlebars can be rotated backwards slightly at the
stem clamp. The best position is found by just getting on your bike and
riding!
Handlebar stem - You should be able to adjust the handlebars so that
they are comfortable. If you cannot do this, buy a stem that is
comfortable. There are many different rise angles, lengths and quill
lengths (part of that stem that fits into the fork).
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