Chains- What is the Deal!
GUIDE How to identify and measure chains for Racing go-kart use
I am often asked the question “Will this chain fit my kart?” and “What is the best pitch to use for my project?” so I’ve decided to write this informative but straight-forward guide focused on the two popular go-kart chain sizes 35 pitch and 219 pitch.
What is Pitch?
Firstly, to explain pitch we need to understand the basic components of the chain. A picture is a thousand words (so to speak) so here’s a diagram of an arbitrary chain:
The pitch of the chain is basically the distance from center of roller to center of roller.
Or, from the center of the link plate to the center of the next link plate (inner plate center to outer plate center).
This is the same distance between the tip of each tooth on a brand-new sprocket of the same pitch:
What types of chains are used on Racing Go Karts?
In Australia, we generally use one of two size chains to transmit power from engines to axles our karts. #35 pitch and #219 pitch. As a general rule of thumb, most 2-stroke karts use #219 pitch chain and most 4 stroke karts use #35 pitch chain, but this is not a hard and fast rule due to the benefits of each type of chain and the purpose of the go kart.
How do I know what pitch I have on my kart?
The easiest way to determine the pitch is to measure either a sprocket or a chain from your kart. If it’s #35 pitch it will measure approximately 10 mm (9.525 mm = 3/8 inch), if it’s #219 pitch it will measure approximately 8 m (7.774 mm). The reason we measure approximately is because these tow chain pitches are measured in imperial inches rather than metric mm. 219 is a very unusual pitch as it is not 5/16 inch as often incorrectly referred to as. It is wise to note that #219 pitch chain is not 8 mm pitch chain – 8 mm chain is Metric and is not used on Racing Go Karts in Australia in general.
#35 Pitch = approximately 10 mm (9.525 mm)
#219 Pitch = approximately 8 mm (7.774 mm)
#40 , #428, #41 & #420) = approximately 13 mm (12.70 mm)
(*NOTE: 41 & 420 plates are spaced closer together (1/4″) compared to 40 & 428 which are 5/16″ – this means you can use a 428 chain on a 420 sprocket, but you can’t use a 420 chain on a 428 Sprocket)
Where do the numbers 35 and 219 come from?
Pitch numbers are arbitrary numbers given to chain sizes as part of the ANSI (American Standard), ISO (International Standard) and BS (British Standard). 35 and 219 pitch chains do not derive their pitch number from any of their properties.
What are the benefits of 219 pitch chain?
1. Smaller diameter sprocket
a. Because 219 pitch chain has a smaller pitch (7.774 mm), more links can occupy a given diameter of sprocket. That means a 219 sprocket with the same number of teeth as a 35-pitch sprocket will be smaller in diameter. That means a larger number of teeth can be used before sprockets foul on the ground or chassis. This improves gearing options.
2. Smoother power transmission / longer sprocket life
a. Because of the smaller pitch, teeth are closer so a more even drive force is transmitted per square mm of sprocket tooth. This reduces the amount of stress on each tooth and provides a marginally improved sprocket lifespan.
What are the disadvantages of 219 pitch chain?
1. Lower strength
a. Because the chain is made from less material, the strength of the components is lower.
2. Higher price
a. Because 219 pitch chain needs to be manufactured to a much higher quality to ensure durability, it is generally more expensive.
3. Fixed length / Non-Breakable
a. 219 pitch chain generally does not come with a removable link due to any removable links compromising the already close tolerance chain. While 219 pitch chain can be broken with a chain breaker, it is not recommended.
What are the benefits of 35 pitch chain?
1. Adjustable length / Breakable
a. Because 35 pitch chain is relatively strong, it can afford to compromise its strength and offer removable links. One of the biggest advantages of 35 pitch chain is the ability to lengthen or shorten it with a removable link. This also proves an enormous advantage where rear axles are driven ‘in-board’ with a sprocket between the bearings.
2. Higher Strength
a. Because 35 pitch chain has marginally larger components, it has increased strength.
3. Lower Price
a. Due to the ability to manufacture 35 pitch chain at good strength at a lower quality of manufacture, prices can be lower.
What are the disadvantages of 35 pitch chain?
1. Larger Sprocket Diameter
a. Because 35 pitch chain has a larger pitch (9.525 mm), less links occupy a given diameter of sprocket. That means a 35 sprocket with the same number of teeth as a 219-pitch sprocket will be larger in diameter. This means a lower number of teeth can be used compared to 219 pitch before the sprocket fouls the ground or chassis. This reduces the gearing options.
2. Less-smooth power transmission / reduced sprocket life
a. Because of the larger pitch, teeth are further apart so a less even drive force is transmitted per square mm of sprocket tooth. This increases the amount of stress on each tooth and provides a marginally reduced sprocket lifespan.
What is the best type of chain to use for my Project?
Factors to consider when choosing an ideal pitch of chain would include:
1. In-board or out-board drive sprocket configuration
2. Availability of engine sprockets
3. Final desired gearing