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The Intricacies Of Mountain Bike Gears

Admin — Thu, 24 Dec 2009 20:30:43 +0000

When you choose mountain bike, it is a good idea to learn more about the gearing systems. This article will explain more about how those systems work. Mountain bike gears are continually becoming more and more complicated and intricate. Today’s bikes can come with up to 27 gear ratios. It is common for a mountain bike today to use nine gears in the back and three sprockets of different sizes in the front for gear ration production. Why so many gears? The most common reason is that a large number of gears allow a rider to pedal at the same pace no matter what terrain that he/she is on. This can be understood better if you think about a bike that just has one gear. Every time you turn the pedals one full turn, then the rear wheel also turns one full turn, too (1:1 gear ratio). For example, your back wheel is measured at 26 inches. If you pedal one full turn, then this would mean that your wheel moved 81. 6 inches. If you are riding at 50 RPM, then you will be able to go 340 feet per minute. This means that you were going 3. 8MPH, which is equivalent to walking speed. This speed is great for going up a hill that is steep, but it is not a good speed for flat ground or racing downhill. If you want your bike to go quicker, then you will need a different ratio. If you want to reach a speed of 25 MPH downhill using a 50-RPM cadence, then you will need to have a 5. 6:1 gear ration. If you have lots of gears on your bike, then you will be able to get that ratio so that you can continue your pedaling at a consistent pace, no matter what terrain you are on or what your speed is. A typical mountain bike that has 27 gears will have six gears so incrementally close to the other that you will not be able to determine that there is any difference between the gears when you change them. Most mountain bike riders decide to choose a gear system with a front socket that is suitable for the slope or terrain that they usually ride on and they stay with this choice, even though it may be more difficult under a heavy load to shift the gears. This is purely a personal decision, but it is simpler to shift between gears when the rear socket, rather than the front one. When you are pedaling uphill, then you will find that it is much better to choose a sprocket that is smaller on the front and then shift gears with the nine gears that are available on the rear. If you are more speeds on the rear sprocket, then you will find that it is much more efficient to ride. Mountain biking needs gears so that you can keep an overall speed going. If you didn’t have gears, then you would find it difficult to build up any speed and you would find it nearly impossible to pound your pedals for extra control. Gears help to move the pedals and enable you to gain that speed.

How Mountain Bike Gears Work

Admin — Wed, 23 Dec 2009 14:31:26 +0000

The gears in mountain bikes just keep getting more and more intricate. The bikes of today have as many as 27 gear ratios. A mountain bike will use a combination of three different sized sprockets in front and nine in the back to produce gear ratios.
The idea behind all these gears is to allow the rider to crank the pedals at a constant pace no matter what kind of slope the bike is on. You can understand this better by picturing a bike with just a single gear. Each time you rotate the pedals one turn, the rear wheel would rotate one turn as well (1:1 gear ratio).
If the rear wheel is 26 inches in diameter, then with 1:1 gearing, one full twist on the pedals would result in the wheel covering 81. 6 inches of ground. If you are pedaling at a speed of 50 RPM, this means that the bike can cover over 340 feet of ground per minute. This is only 3. 8 MPH, which is the equivalence of walking speed. This is ideal for climbing a steep hill, although bad for ground or going downhill.
To go faster you’ll need a different ratio. To ride downhill at 25 MPH with a 50 RPM cadence at the pedals, you’ll need a 5. 6:1 gear ratio. A bike with a lot of gears will give you a large number of increments between a 1:1 gear ratio and a 6. 5:1 gear ratio so that you can always pedal at 50 RPM, no matter how fast you are actually going.
On a normal 27 speed mountain bike, six of the gear ratios are so close to each other that you can’t notice any difference between them.
With actual use, bike riders tend to choose a front sprocket suitable for the slope they are riding on and stick with it, although the front sprocket can be difficult to shift under heavy load. It’s much easier to shit between the gears on the rear.
If you are cranking up a hill, it’s best to choose the smallest sprocket on the front then shift between the nine gears available on the rear. The more speeds you have on the back sprocket, the bigger advantage you’ll have.
All in all, gears are very important to mountain bikes as they dictate your overall speed. Without gears you wouldn’t be able to build speed nor would you be able to pound pedals. The gears will move the pedals and help you build up speed.
There are all types of gears available in mountain bikes, all of which will help you build up a lot of momentum if you use them the right way.

Second Hand Mountain Bike – a Buyers Guide

Admin — Mon, 21 Dec 2009 22:13:49 +0000

Good mountain bikes these days are by no means cheap. However, a knock-on effect of their expense is that they are being built with much stronger and more durable materials, meaning there are literally thousands of great second-hand bikes out there for a fraction of the cost of a new one. You just need to know what to look for.

There are usually many elements to a second-hand mountain bike and each bike tends to vary in its make-up. Outlined here are the key points to look out for on the more common components.
Wheels
Turn the bike upside-down and check the condition of the rims. Look out for dents or fractures in the metal and spin both wheels to see if they run true. Any problems with the rims will hinder performance and might mean you’ll need to fork out for a new pair straight away. Check each spoke individually for tightness or damage. Spokes can be tightened or replaced easily but loose spokes can be an indication of a misshaped wheel. When spinning the wheels, pay attention to how the bearings function. The wheels should spin almost silently and with very little resistance. Any noise or resistance to the wheel turning could be a problem with the bearings and may mean they need replacing.
Brakes
There are a number of different types of brake used on modern bikes but they all do the same job, so the best way to test them is to get on the bike and use them to stop. Use both brakes individually in order to highlight any problems and look out for weak braking power, excessive noise, shuddering or having to use a lot of hand force to engage the brakes. Also check the brake cables for any fraying or splitting. . . any damage to the cables can spell trouble for braking power, especially for hydraulic brake reservoirs, so give them a good inspection. To be honest, most problems can be corrected by making small adjustments but be prepared to pay for new cables, pads, levels and even brake-sets if there is significant wear/damage
Frame
Arguably the most important part of the bike to inspect. Almost every frame is different but there are common elements that should be checked. First examine the welds in the frame. Are the any cracks or clear weak spots? How about the top tube and down tube, are they in good condition? Don’t be afraid to apply a reasonable amount of force to each part of the frame, it should be able to hold up to a lot and if you see any weakness or excessive movement then the frame is severely compromised. In some instances the frame can be re-wielded or strengthened but it’s unlikely to be worth your time and there are plenty more bikes in the sea. The general condition of the frame should be good. If there are lots of dents or nicks in the frame it may suggest the bike’s had a lot of use or has been badly treated.
Saddle
Check the condition of the saddle covering and have a look underneath at the fixings also. Try adjusting the seat up and down. This should be easy to do and the seat post shouldn’t snag at any point. If it does then the saddle post or seat tube of the bike could be misshaped.
Suspension
As with other elements of a mountain bike, suspension can come in many forms, so again the best way to test it, is to use it. To test the front forks, repeatedly apply pressure downwards on the handle bars and see how much travel there is in the forks. Look out for restricted movement or too much movement – both of which can suggest damage. Remember however than many types of suspension allow for adjustments to the travel in order to give a firmer or softer ride, so test at both extremes that the forks offer.

Some forms of suspension use oil in the forks. If this is the case then clean both forks, apply some downward pressure on the handle bars and see if there is any oil on the forks when the suspensions expands back out again. If there is oil then there’s most likely a problem with the fork seals and they’ll need replacing.
To check the rear suspension, place pressure downwards on the saddle. Like with the front forks, there should not be too little or too much movement. However, advances in rear suspension have allowed adjustment to the travel here as well, so take this into account.
Chain
Depending on quality, the price of a new chain can be quite steep so you’re going to want to inspect the condition of the current one. A good chain shouldn’t have any rust on it, it should be well-fitting and each link should be able to pivot on the ones either side. If two links will not move independently of each other then they can very easily be replaced but beware, one locked link often means there will be others. Tip the bike upside down and give the chain a good few rotations. It should be smooth, quiet and easy to turn.
Gears
The most common type of gears on modern mountain bikes comprises of a front and rear derailleur, a set of rear sprockets (aka cassette) and a set of front chain rings.
Take a good look at the condition of the sprockets and chain rings first. They can sometimes become damaged and the teeth can bend or pick up nicks, both of which will need repairing. Check if they are secure by trying to move them both away from and towards the bike. Any wobble or sliding of the sprockets or chain rings will need looking at.
The front derailleur should guide the chain onto the chain rings smoothly. Check that it hasn’t been bent out of place or picked up any serious damage. Impact marks on derailleurs are a key giveaway of bike abuse. The rear derailleur should do a similar job, guiding the chain on the rear sprockets with ease and smoothness. Push the bottom of the derailleur forwards to give slack to the chain and let it move back into its resting position. This line of travel should again be smooth and require little effort to achieve it. Check the cables that run to both derailleurs for fraying or other damage and also check the gear-changing apparatus on the handlebars for ease of use and possible damage.

Whilst a visual inspection of the gearing system is important, the best way to actually get an idea of the condition of the gears is to use them. Ride the bike around a bit and go through every gear ratio possibility there is. The changing between gears should happen quickly, smoothly and without too much noise. When cycling in each gear the action should be the same and there should be no clunking or clicking coming from the derailleurs. Tuning can often fix most problems with gearing but the person selling the bike should have sorted this themselves first, and if they haven’t then it can sometimes suggest there might be more terminal damage that couldn’t be fixed without new parts
Crankset
When cycling the bike it’s likely that you would notice any problem with the crankset if there were any. Things to look out for would be any movement of the bottom bracket, other than the rotation in the single dimension intended. Likewise, any side-to-side or up and down movement should be investigated thoroughly. Feel for resistance when pedalling and listen out for any unusual sounds like scraping or clicking. If there are odd sounds then it may be that the bearings have gone or that there is movement in the bottom bracket shell. It’s worth have a visual check of the crankset as well to sight any fracturing or bending of the crank arms (they will need replacing if there is) or any other damage to the bottom bracket or indeed pedals.

Handlebars and Stem
There is often a lot of force put through the handlebars and stem of the bike, especially during a heavy landing. For this reason they are usually well reinforced and built from strong materials. However, bending, splitting and even serious fracturing of the metal is not uncommon and should be looked for. Stickers can sometimes hide damage and you should ask for them to be removed before you buy. Also look out for repair work on the bars or stem (as indeed you should for the whole frame) and be cautious of anything that looks like it has been re-welded or amateurishly repaired.
To reiterate what has been said previously, the best way to test a used mountain bike is to give it a good ride. If everything on the bike is in good condition then the seller shouldn’t mind you testing it, and if there are any problems, they will soon become apparent.

Cross Country Mountain Biking

Admin — Thu, 03 Sep 2009 10:24:47 +0000

Cross country mountain biking is cross country at

its finest. Where free riders and downhill bikers

use four wheel bikes and ski lifts to get them to

their destination, cross country bikers get to

the top of the mountain by the ride. Though free

riding is very popular, the life vein of the sport

has always been cross country biking.

Just as cross country riders are a different breed,

the bikes they ride are as well. The cross country

bike is completely different in many ways from other

types of mountain riding bikes. The premise for

cross country riders is speed. Everything about

their bikes revolve with the idea of making the

bikes faster and faster.

Bikes used in cross country mountain biking can

be fully rigid frame, hardtails, or even full

suspension frames. Through the years, the cross

over to full suspension has become very popular.

The weight difference between free ride bikes and

cross country bikes are considerable. You’ll be

extremely hard pressed to find a bike that weighs

more than 24 pounds, and even that weight can be

heavy. Free ride bkes weigh close to 40 pounds,

which makes the difference in weight pretty close.

If you’ve never tried cross country mountain biking,

you’ll probably find it to be a break from the

ordinary. Even though this type of biking involves

trails, it’s normally the type of terrain that

beginners wouldn’t want to ride. Involving hills

and rough terrain, cross country biking offers

quite the rush.

For mountain bikers everywhere, cross country is

the way to go. It offers you a new assortment of

bikes, new areas to bike, and a new twist to

mountain biking as you know it. If you’ve been

looking for a mountain biking rush, cross country

mountain biking is what you need to be experiencing.

By: John Ugoshowa