As you dig through the marvels of the dirt biking world, curiosity gets in your way. You might also be inclined to ask this question: Do dirt bikes have gears?
Well, the short answer is yes. To follow through this aspect is perhaps a series of questions, like “how many gears does a dirt bike have?”. But worry no more, we will be elaborating the details in the succeeding sections.
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Purpose of Dirt Bike Gears
As long as a vehicle possesses an engine, the gears will be always present. They are used to transmit power to the wheels from the source engine. In addition, it also dictates rider control in the speed of the engine and power output.
To add to the functionality of the gears in a dirt bike is the presence of a clutch. This coupled with the gear system in dirt bikes avoids excessive wear when the engine starts to run.
With the varying gears present in dirt bikes, this implies a varying gear mechanism to optimize biking experience.
How Gears Work in Dirt Bikes
Typically, there are five gears on a dirt bike, although bikes with four or six gears are likewise popular. The wheels revolve more quickly when the gear is higher, while more torque is applied to the wheels when the gear is lower.
Hence, a high gear, typically fifth, is excellent if a rider wants to navigate at a higher speed on smooth surfaces. Likewise, a lower gear is more suitable to provide sufficient energy to power through a rougher terrain.
To perform shifting between gears, you will get into gear shifter positions, then use your foot’s midsection as a pivot point and place it on the foot peg. The gear shift lever will be moved using the front of your foot.
Common Gear Ratios for Dirt Bikes
In dirt bikes, the gears are made up of interlocking sprockets which work together in producing a desired ratio of the torque and rpm. This gear selection collectively dictates the final gear ratios in the dirt bikes.
Also known as the sprocket ratio, gear ratio means the teeth count on the back sprocket over the teeth count on the front sprocket. The higher the gear ratio number, the lower the gearing. Hence more teeth in the back sprocket lowers the overall gearing.
Depending on the intent of your dirt biking experience, a good understanding of the gear ratio is necessary. For faster acceleration purposes and for tougher terrains, front sprockets should be smaller and back sprocket is larger to achieve a lower gear ratio.
On the other hand, if the intent is for higher top speeds which is recommended for biking on sandy tracks, the front sprocket should be larger hence resulting gear ratio is higher.
As a guide for common dirt bike gear ratios, kindly refer to the following diagram:
As a tip, when changing the teeth count of the sprockets, one tooth change in the front sprocket is equivalent to three to four teeth changes in the rear sprocket.
Pros and Cons
For optimal riding experience, gears in dirt bikes are really necessary and here are the some of the pros to remember:
- Lets the rider optimize dirt bike efficiency and engine performance through different gear shifts
- Gives terrain flexibility of the dirt bike
- Alteration of power characteristics to deliver increased accelerations which results in faster riding speeds.
The disadvantage will only happen with the absence of gears. In such a case, a bike cannot move backwards since it only goes in a single direction. This will be very disadvantageous especially when navigating on rough roads.
Gears on Two Versus Four-Stroke Dirt Bikes
Although the number of gears in a 2 stroke and 4 stroke dirt bikes are identical, the ease of usage may somehow be different. In a 4 stroke dirt bike, gear selection may not be necessary compared to a 2 stroke dirt bike since it can sustain any gear at any speed.
The 2 stroke dirt bikes, on the other hand, will require constant gear shifting which demands more effort from the rider.
Types of Dirt Bike Transmissions
Apart from the gears, bike transmissions should also be taken into account if you decide to select your own dirt bike. Generally, they are classified into three types: manual transmission, automatic transmission, and semi-automatic transmission.
Manual vs automatic transmission
What then is the difference between the bike transmission types? To summarize, here is a tabulated presentation for comparison purposes:
|Manual Transmission||Automatic Transmission|
For a mini bike, it is highly likely to be fully automatic as it is designed to be used by young bike riders.
On the other hand, adult bikes with automation are usually considered semi automatic dirt bikes instead. Although with a gearbox, such models are still operated with a foot pedal to make gear changes for opening and closing the throttle.
In addition, tabulated below are some parts to watch for to know if a dirt bike has a manual or automatic transmission:
|Bike Part||Manual Transmission||Automatic Transmission|
|Pedal||Located on the left side which can be moved up and down||Not present|
|Handles||Located on the left hand side which works as a clutch||Dirt bikes without clutch|
Tips in Maintaining the Gear System of a Dirt Bike
To ensure longevity of your gears, part of the activities you have to do is gear maintenance. Kindly watch out for the following warning signs that would signal replacement of your bike gear parts:
- Sprockets– wearing of tooth, cupping, leaning of teeth
- Chain– rust formation, wear pattern on top and bottom
- Drive chain components (guide, slide, rollers)– loose bolts, exposed metal, chain cutting
The gear system of a dirt bike operates together hence it is advisable to replace the said components together. In addition, the parts equally wear while operating the bike. It is also advisable to look into the service manual to check the service limit of your bike part.
Gears are definitely an essential aspect on vehicles like dirt bikes hence answering the question “do dirt bikes have gears?” should be a resounding yes.
Moreover, it is equally important to know how gears work and how it contributes to optimizing the speed and riding experience of your dirt bike. That being said, hopefully this guide lets you assess on what to consider for your next dirt bike purchase.