Motorbike Chain Abrasion Issues
Similar to our previous article relating to motorcycle chain alignment issues, many factors can also cause the same chain to face abrasion issues. For obvious reasons, such as repair and expense, this is something you need to avoid as much as possible. Although there are many influencing factors, the main one tends to come in the form of wear, friction or a trauma endured by the motorcycle and its components.
Unpicking the term ‘Abrasion’
When it comes to caring for your motorcycle, understanding the terms involved in its maintenance and preservation is key. Abrasion is a term that is intrinsically linked to your chain, but what does it actually mean?
According to The Cambridge Dictionary, abrasion is the process of rubbing, scraping or the wearing away of the surface of something. With this in mind, it’s obvious that any motorbike chain will naturally suffer from abrasion over time.
The key, therefore, is not preventing abrasion altogether (as that can never happen) but reducing it where possible and identifying it before it becomes a more serious problem that either damages the bike or puts you in danger.
The significance of your chain
You’ll already know this but to ensure we have a complete picture it’s worth saying. A motorcycle’s chain connects it’s engine (which generates the power) to the rear tyre (which provides momentum). As such, any movement of the bike results in an opportunity for abrasion to occur.
Furthermore, a typical motorcycle chain consists of approximately five hundred pieces providing multiple points of potential failure due to excessive wear, rubbing, or reduced lubrication to name a few.
With this in mind, any damage to the chain can result in a loss of power being transferred to the tyre. This drop off in power transfer means your engine needs to work harder to achieve the same speeds. As the engine works harder it is also more likely to suffer increased wear.
The increased power from the engine also puts more strain on the chain resulting in further damage - and so the cycle repeats getting increasingly worse until either you intervene, or a catastrophic failure occurs.
Common Causes of Motorcycle Chain Abrasion
Abrasion can be caused by almost anything as the chain is such an exposed part of the bike. There are a number of common causes, however, which we’ve detailed below;
- Riding conditions such as excessive heat or cold
- Environmental impacts such as dust, dirt, or stones being 'kicked up' into the chain
- Chain tension
- Riding style and type of motorcycle engine
- Quality of chain and sprockets
- Mechanical issues
The question then becomes how you diagnose these issues before they become a serious problem.
Below we have listed some useful warning signs to keep an eye out for;
- The chain suffering rapid pin/bush wear leading to chain pitch extension resulting in a visual lengthening of the chain*
- A loosely hanging chain (or out of measurement)
- A chain ‘tugging’ whilst riding in the lower gears
- The chain becoming dislodged
*This occurs when the motorcycle chain wears at the point where inner and outer side plates are connected by the pin. The rolling action of the chain pin and bush then constantly rub against each other. If this contact point is not sufficiently lubricated, the pin will wear into the bush, thus allowing it to sit deeper in the bush. As this usually happens over many links of a chain, the chain physically becomes longer, up to the point where adjustment is no longer possible.
If these symptoms are not picked up on, you may then start to experience the following as the problem becomes more serious.
- New grating noises are occurring as the chain runs over the sprockets
- When you open the throttle the chain makes a clanging motion
- Kinks or stiff spots
- Separating link plates
- Excessive stretch resulting in loose components
- A jerky feeling and loud sounds when riding
Many of the above can result in your chain becoming worn-out altogether. As always, prevention through regular maintenance is something we strongly advise.
Further examples of abrasion
Although there are various potential abrasion issues, they tend to have one overwhelming factor in common: wear, rubbing, or scraping has occurred. Often this is due to a build-up of excessive wear over time. As such, it will likely have been caused by many factors.
Inevitably, your motorcycle chain will encounter wear and tear daily, with little you can do to stop it. However, your responsibility to your bike (and to yourself) is to ensure replacement of the chain is prolonged for as long as possible through regular maintenance.
Abrasion can occur within both the chain and the sprockets, which can look like the following: Impact within the Chain -
- Loose pins
- Damaged rollers
- Dry or rusty links
- Kinked or binding links
- Excessive wear
- Excessive slack
Impact within the Sprocket
- Worn teeth
- Broken or chipped teeth
- Loose sprocket nuts
Maintenance – prolonging the life of your motorcycle chain
To obtain the maximum performance from a chain and sprocket set, maintenance needs to be planned and carried out on a regular basis. This will not only ensure optimum chain life, but will reduce downtime and limit inconvenience when chain replacement is necessary.
The most common source of abrasion occurs within the chain mechanism itself. As such, regular lubrication of your chain should be high on your maintenance checklist. In fact, an effective lubrication routine will likely solve 80% of potential issues.
Plan to lubricate your chain every 500 to 1,000 miles or once every month, whichever occurs sooner.
The health of your motorcycle chain and sprocket should be inspected on a regular basis, whether that’s every single ride or once a week. When inspecting the bike, check for these issues that might require new parts or adjustments. More explanation on this process is provided below.
Chain Cleaning: To prevent dangerous gunk build-up, cleaning and inspecting a motorcycle chain should be a key part of regular maintenance for any owner. A chain left dry and unclean can translate into costly problems later on. The abrasive nature of road grit can wear down the chain and sprocket, while a lack of lubrication can dry out the seals or create unnecessary friction that could damage the chain and sprocket.
You will find most motorcyclist opinions on how to clean your chain and with which precise cleaning products differ from person to person. For chains in a good, well-maintained condition, hot soapy water works just fine. It also depends on how you are cleaning it, in terms of fully taking the chain off your motorcycle, in the case of a more deep clean.
With the chain off the bike, you can leave it to soak overnight in degreaser, before giving it a thorough scrubbing with a toothbrush. Or you can put it in an old water bottle full of degreaser and shake it clean
For quick motorcycle chain clean-ups, you can wipe down your chain with a rag moistened with diluted (1:3) Heavy Duty Cleaner to remove superficial grime before applying lubrication. You should give your drive chain a deep clean about twice a season or more, depending on frequency of use.
Taking preventative actions
Here at Renold, we want to help you diagnose any potential chain concerns in as short a time as possible. We recommend that the quickest way to check the status of your drive chain is to get on your hands and knees and physically inspect it from a close-up angle.
How to inspect your chain and its sprockets
Upon inspecting, the first signs of abrasion that you need to look for are a rusty chain, binding links and overly pointed sprocket teeth. These are all obvious visual signs that these components need replacing.
Fortunately, chain drive components are easy to visually inspect on most bikes so it shouldn't take long for you to determine if you need to buy a new chain and sprockets. Be mindful that undertaking such a task may require getting your hands dirty, so it might be a good idea to grab some gloves before inspection. A bright flashlight really helps, as well.
Sidenote: Your service manual will probably provide a procedure for determining how worn the chain is by hanging a weight on it and measuring the length of a specified number of links.
Simpler chain inspection:
Another, much easier way to check for a worn chain is to try to pull the chain away from the rear of the sprocket on the rear wheel. If the chain is worn, you'll reveal about half a tooth of the sprocket. A new chain will wrap around the sprocket snugly and won't pull away.
At the far back end on the rear sprocket, pull the chain away from the teeth (parallel to the ground). A new chain will barely move. If you can pull it back to expose half a tooth or more, you need to replace the chain. You can perform this task just by spending a couple of extra seconds by the rear wheel when you’re checking its tire pressure before a ride. Again, this is something we recommend you do prior to every outing on your motorcycle.
During your inspection, don’t forget to examine the sprockets, too. Look for sprocket teeth that are hooked, pointed or chipped They should not be arched on one side, like a cresting wave. If it is, you need to replace the sprocket, and your chain is probably nearing the end of its life, too.
While chain wear is absolutely normal and to be expected, correct maintenance reduces the impact of these factors and dramatically increases chain life. It is a common misconception that chain wear means the chain stretches and therefore becomes longer (in the sense that material stretches). However, this is not the case. When you compare a worn chain against a brand-new chain it will be difficult to see a difference until you put them under a load.