Your energy input in each case is roughly the same. The part about knee injury really is a key one. Conversely, there also comes a point where spinning any faster becomes inefficient and can even unbalance you. It makes sense to shift into a higher gear again in order to reduce your cadence. The ideal cadence will be very personal but is often considered to be in the 70 to rpm range. The key thing with shifting gears is anticipation. Look ahead and try to predict how your speed will change and how you are likely to need to change gears.
As you come to a tight corner, anticipate that you will need to slow down and shift into a lower gear so you can accelerate out of the corner more easily.
Equally, if you need to stop at some traffic lights, shift into an easier gear so that you can set off more easily when the lights turn green. Always ensure that you are pedalling to perform smooth shifts and shift gradually across the range of gears to find the right one.
Another thing to avoid is cross-chaining. The extreme angles this puts the chain at can result in increased wear and high loads on the drivetrain. Conversely, hub gears or gear boxes can usually be shifted when at a standstill.
The key to keeping your gears running nicely is to ensure you keep them clean and well maintained. In fact, keeping things clean in general helps you keep on top of maintenance and lets you identify any potential issues before they become more serious. As discussed previously, hub gears tend to be lower maintenance, though you may still have to adjust cable tension because it still stretches gradually over time. General maintenance like this works wonders in the long run because a well adjusted and maintained bike is kinder on your components overall.
Finally, we would recommend checking your chain for wear regularly with a cheap tool. Replacing your chain is much cheaper than replacing other worn out components on your bike. Equipped with this knowledge, get out there and start using your gears.
The basics explained Best mountain bike how to choose the right one for you. An external drivetrain with a front and rear derailleur. Jonny Ashelford. Pinion gearboxes have found a niche mainly on mountain bikes.
A Gates Carbon Drive belt requires less maintenance than a traditional chain. Fixies cannot freewheel. Trigger shifters on a Specialized Sirrus commuter bike. BUT to view these as 21 independent gears, numbered 1 to 21 would be wrong. To understand why, we first need to understand gear ratios. In simple terms, a gear ratio on a bike refers to how many times the back wheel will rotate for each full turn of the crank arms pedals.
If we have a chainring with 30 teeth and a sprocket with 30 teeth, there is no difference between the two; one full revolution of the pedals will result in one full revolution of the wheel.
As a ratio, this is 1 to 1 If we have a chainring with 30 teeth and a sprocket with 10 teeth, the chainring is 3 times bigger than the sprocket; one full revolution of the pedals will result in THREE full revolutions of the wheel. As a ratio, this is 3 to 1 As a ratio, this is 2 to 3 Gear Inches In the UK, bicycle gearing is expressed typically as gear inches or gear centimetres for the metric among us. If we imagine that our pedals were attached directly to the driving wheel we can use the gear ratio to determine the effective size of the imaginary driving wheel.
Think of a Penny Farthing with its huge front wheel. Progression Metres Through most of Europe, bicycle gearing is typically expressed as progression metres.
Again, imagining our pedals attached directly to the driving wheel, Progression Metres refers to the distance in metres that we will travel for one full revolution of the pedals. Now we have an idea of what gear ratios, gear inches and progression metres are, we can start to look back at our "21 Speed" bike and see what happens when we chart the gear ratios for real.
You can do this for yourself for the gears on your own bike using our gear calculator. Look carefully at the values for a 28t chainring with a 28t sprocket and you'll see it has a ratio of For a 48t chainring with a 12t sprocket it has a ratio of The first row of the chart is the 7 gear ratios we have with the smallest 28t chainring selected.
The highest gear ratio is 28t with 12t; a ratio of 2. Now look on the second row where we have the middle 38t chainring selected. What this results in is that rather than there being 21 "speeds", there are three ranges of seven gears.
Each of our three gear ranges overlaps onto the gear ratios of its neighbour. In fact, if you look closely, you will notice that almost every gear ratio when the middle 38t chainring is selected is almost duplicated by ratios on the 28t and 48t chainrings. How many gears speeds do I have? If you have a multi-speed bicycle, there are two options for determining exactly how many gears your bicycle has:.
Counting the gears on your rear wheel. If you have external gears, stand behind your bike and take a look at the right side of the rear wheel. There should be a cluster of gears on the right-hand side. This is your cassette. Count the number of gears or steps in the cassette. Don't forget to count the one that the chain is on. Looking for the highest number on your handlebar shifters. Most modern multi-speed bicycles have shifters on the handlebars with the number of gears clearly printed.
The highest number on the shifter that moves the chain on your rear set of gears is what you are looking for. On the crankset, the smallest chainring is closest to the frame. The smaller the chainring, the easier the pedalling. As we move the chain away from the centre line of the bike, the pedalling gets harder but you go faster.
Most bikes built in the last few years have between 8 and 11 cogs in the cassette. The largest cogs are closest to the wheel and the gears are numbered from the inside out. The marketing department likes to multiply the number of cogs by the number of chainrings because big numbers are impressive. The chain gets moved from one cog to another or one chainring to another by means of a derailleur.
The rear derailleur is a little more complex as it has two jobs. Like the front, it guides the chain from one cog to the next, but it is also responsible for maintaining chain tension and taking up the slack when we move from bigger gears to smaller ones. The rear derailleur is much more effective at switching gears while pedalling hard. It is important to note however, that in order to switch gears the chain must be moving forward. With both the front and the rear derailleur, when the shift cable is pulled, it will move the chain to a larger gear.
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