When you feel the need for a bit more top end or faster acceleration, changing your sprocket ratios is a fast way to achieve those results.  Playing around with a combination of front and rear sprocket sizes can allow you to tune your bikes acceleration and top speed to suit the type of terrain you are riding on a particular day, or most regularly. We will also cover the types of sprockets and chains that are available to buy from Moto Hut and the relative differences of each.
Sprocket & Gearing Info

 

Front Sprockets

Front sprockets are all made from a high quality steel, with suitable case hardening.  Different brands have different quality steels, different designs and different manufacturing techniques.  These contribute to wear resistance and longer life.

Grooved sprockets have a groove machined into them to allow mud to fling off easier such as on offroad bikes.

Ultralight sprockets have holes machines into them to reduce the weight of the sprocket.  Typically used by racing teams.

Standard sprockets have no additional machining to them, and offer OEM type functionality.

Front sprocket sizes can be changed up to a point.  Physically, there is a limitation to how big you can go and that this depends on the amount of clearance your bike has between the front sprocket shaft and surrounding casings and sprocket guards.  Going too big may cause interference between the sprocket and casings which will lead to damage.  Not a good thing.

A single tooth change on a front sprocket is about equal to a 2-tooth change on the rear sprocket.

 

Rear Sprockets

Rear sprockets can be made either from steel or aluminium, depending on the application. We compare them in the following chart:

  STEEL ALUMINIUM
Weight Better
Durability / Lifespan Better
Price Better
Looks Better

Changing rear sprocket sizes a tooth at a time results in a less severe changes, and is recommended if you are fine tuning your bikes response or are not wanting a radical change.

 

Chains

There are good chains and there bad chains.  Don't expect a R300 chain to perform better or outlast a R2000 chain. Its one of those things where you pay for what you get!  Having said that, lets look into the various technical aspects of a chain

 

Chain Strength

The strength of the chain must be sufficient for the engine size and application of your motorcycle. Chain strengths are generally classified according to the engine capacity (CC) of the motorcycle. The higher the engine capacity, the stronger the chain needs to be.

Buying on price alone will likely end in disaster - chains for superbikes for example cost proportionately more than offroad and smaller capacity road bikes, so be sure that amazing deal you think you're getting does come at the cost of inferior strength.

Chain Length

Chain length is measured in the number of links a chain has, eg. 120L means 120 links long.  Buying a chain that is too short will not provide enough chain for you to adequately adjust your chain.  If anything, buy a length longer than is required as you can cut the chain to length.  While on this topic, make sure to use a proper chain cutting and riveting tool!  A grinder and chisel are not considered "proper"

Chain Size

This must be the correct size to fit the sprockets, as the sprockets are also measured and manufactured according to the chain size.  Chain size is represented by a 3 digit number: 415, 420, 428,520, 525, 530, 630 etc.  Effectively, two measurements define a chain size and these are shown in the table below:

Chain No Pitch Width
415 12.7mm 4.76mm
420 12.7mm 6.35mm
428 12.7mm 7.94mm
520 15.875mm 6.35mm
525 15.875mm 7.93mm
530 15.875mm 9.53mm
532 15.875mm 9.53mm
630 19.05mm 9.53mm
632 19.05mm 9.53mm

 

Seal Type (Std vs O-Ring vs X-Ring)

The seal type of the chain defines the type of seal fitted on the links.  If a chain does not have seals, it's considered a "standard chain". If it has a seal, it can have the traditional o-ring seal, or the more modern x-ring or z-ring variants.  Let's understand them better by looking at the friction and wear-resistance capabilities in the charts below.

Chain friction is the highest on an O-Ring chain, and significantly less on an X or Z-Ring chain, due to the newer design.  Standard chains have the least friction as they have no seal surfaces in contact with the steel links.  Reduced friction = greater performance, and the less your engine has to work to turn the rear wheel!

 

Chain Friction Comparison


Chain wear resistance is remarkeably better on sealed chains.  That means, the standard chain will not last nearly as long as a sealed chain (all things being equal).  O-Ring chains show their age yet again, and do not offer nearly as good wear resistance as the X or Z-Ring chain designs, which offer the most superior wear resistance.

 

Chain Wear Resistance Comparison
 

Connecting Links

These differ depending on the chain application.  Chains used on higher capacity bikes (say 600cc upwards) typically use a RIVET link while smaller capacity bikes using a CLIP link. Clip links can be installed by hand without special tooling, while rivet links must be fitted using a chain riveting tool.  In some cases, certain chains that you buy will have both a rivet and a clip link in the box, however it is still advisable to fit the correct link for your application.
 

 

GEAR RATIOS 


Gear Ratio Formula

Now that you understand the basics of sprockets and chains, let's discuss making changes changes to the gearing of your bike to get a certain outcome.  
 
Basically, the gear ratio is a simple formula:
  • Gear Ratio = Rear Teeth / Front Teeth

Example:   Front sprocket = 12T, Rear sprocket = 52T.  Gear ratio = 52/12 = 4.33


ACCELERATION

  • The HIGHER the gear ratio, the faster you ACCELERATE

Increase your acceleration with:

Smaller front sprocket
Bigger rear sprocket


TOP SPEED

  • The LOWER the gear ratio, the greater your TOP SPEED

Increase your top speed with:

Bigger front sprocket
Smaller rear sprocket

 

Gear Ratio Table

We've made your life easier by displaying a list of all the most common gear ratios below:

  10 11 12 13 14 15 16 17 18 19 20  
65 6.50 5.91 5.42 5.00 4.64 4.33 4.06 3.82 3.61 3.42 3.25 65
64 6.40 5.82 5.33 4.92 4.57 4.27 4.00 3.76 3.56 3.37 3.20 64
63 6.30 5.73 5.25 4.85 4.50 4.20 3.94 3.71 3.50 3.32 3.15 63
62 6.20 5.64 5.17 4.77 4.43 4.13 3.88 3.65 3.44 3.26 3.10 62
61 6.10 5.55 5.08 4.69 4.36 4.07 3.81 3.59 3.39 3.21 3.05 61
60 6.00 5.45 5.00 4.62 4.29 4.00 3.75 3.53 3.33 3.16 3.00 60
59 5.90 5.36 4.92 4.54 4.21 3.93 3.69 3.47 3.28 3.11 2.95 59
58 5.80 5.27 4.83 4.46 4.14 3.87 3.63 3.41 3.22 3.05 2.90 58
57 5.70 5.18 4.75 4.38 4.07 3.80 3.56 3.35 3.17 3.00 2.85 57
56 5.60 5.09 4.67 4.31 4.00 3.73 3.50 3.29 3.11 2.95 2.80 56
55 5.50 5.00 4.58 4.23 3.93 3.67 3.44 3.24 3.06 2.89 2.75 55
54 5.40 4.91 4.50 4.15 3.86 3.60 3.38 3.18 3.00 2.84 2.70 54
53 5.30 4.82 4.42 4.08 3.79 3.53 3.31 3.12 2.94 2.79 2.65 53
52 5.20 4.73 4.33 4.00 3.71 3.47 3.25 3.06 2.89 2.74 2.60 52
51 5.10 4.64 4.25 3.92 3.64 3.40 3.19 3.00 2.83 2.68 2.55 51
50 5.00 4.55 4.17 3.85 3.57 3.33 3.13 2.94 2.78 2.63 2.50 50
49 4.90 4.45 4.08 3.77 3.50 3.27 3.06 2.88 2.72 2.58 2.45 49
48 4.80 4.36 4.00 3.69 3.43 3.20 3.00 2.82 2.67 2.53 2.40 48
47 4.70 4.27 3.92 3.62 3.36 3.13 2.94 2.76 2.61 2.47 2.35 47
46 4.60 4.18 3.83 3.54 3.29 3.07 2.88 2.71 2.56 2.42 2.30 46
45 4.50 4.09 3.75 3.46 3.21 3.00 2.81 2.65 2.50 2.37 2.25 45
44 4.40 4.00 3.67 3.38 3.14 2.93 2.75 2.59 2.44 2.32 2.20 44
43 4.30 3.91 3.58 3.31 3.07 2.87 2.69 2.53 2.39 2.26 2.15 43
42 4.20 3.82 3.50 3.23 3.00 2.80 2.63 2.47 2.33 2.21 2.10 42
41 4.10 3.73 3.42 3.15 2.93 2.73 2.56 2.41 2.28 2.16 2.05 41
40 4.00 3.64 3.33 3.08 2.86 2.67 2.50 2.35 2.22 2.11 2.00 40
39 3.90 3.55 3.25 3.00 2.79 2.60 2.44 2.29 2.17 2.05 1.95 39
38 3.80 3.45 3.17 2.92 2.71 2.53 2.38 2.24 2.11 2.00 1.90 38
37 3.70 3.36 3.08 2.85 2.64 2.47 2.31 2.18 2.06 1.95 1.85 37
36 3.60 3.27 3.00 2.77 2.57 2.40 2.25 2.12 2.00 1.89 1.80 36
35 3.50 3.18 2.92 2.69 2.50 2.33 2.19 2.06 1.94 1.84 1.75 35
34 3.40 3.09 2.83 2.62 2.43 2.27 2.13 2.00 1.89 1.79 1.70 34
33 3.30 3.00 2.75 2.54 2.36 2.20 2.06 1.94 1.83 1.74 1.65 33
32 3.20 2.91 2.67 2.46 2.29 2.13 2.00 1.88 1.78 1.68 1.60 32
31 3.10 2.82 2.58 2.38 2.21 2.07 1.94 1.82 1.72 1.63 1.55 31
30 3.00 2.73 2.50 2.31 2.14 2.00 1.88 1.76 1.67 1.58 1.50 30
29 2.90 2.64 2.42 2.23 2.07 1.93 1.81 1.71 1.61 1.53 1.45 29
28 2.80 2.55 2.33 2.15 2.00 1.87 1.75 1.65 1.56 1.47 1.40 28
27 2.70 2.45 2.25 2.08 1.93 1.80 1.69 1.59 1.50 1.42 1.35 27
26 2.60 2.36 2.17 2.00 1.86 1.73 1.63 1.53 1.44 1.37 1.30 26
25 2.50 2.27 2.08 1.92 1.79 1.67 1.56 1.47 1.39 1.32 1.25 25
24 2.40 2.18 2.00 1.85 1.71 1.60 1.50 1.41 1.33 1.26 1.20 24
23 2.30 2.09 1.92 1.77 1.64 1.53 1.44 1.35 1.28 1.21 1.15 23
22 2.20 2.00 1.83 1.69 1.57 1.47 1.38 1.29 1.22 1.16 1.10 22
21 2.10 1.91 1.75 1.62 1.50 1.40 1.31 1.24 1.17 1.11 1.05 21
20 2.00 1.82 1.67 1.54 1.43 1.33 1.25 1.18 1.11 1.05 1.00 20
  10 11 12 13 14 15 16 17 18 19 20