Motorcycle engine vibration are always a cause of concern when the vibration is in higher amounts. If left unchecked, the motorcycle components can start to dysfunction and might lead to higher damages.
What causes excess engine vibration in motorcycles? Excessive motorcycle engine vibration is caused by loosened engine mount bolts, out of sync carburetor, out of tune engine, or cracked frame or suspension components.
The solution to reduce this high engine vibration is to tighten the mount bolts, synchronize the carburetor, tune and service the engine, or repair and replace the damaged frame and suspension components, depending on the root cause.
Let us deep dive into each of these causes and their solution in detail.
#1. Loosened Engine Mount Bolts
The most common reason for an increased and higher vibration in the motorcycle engine is loosened engine mount bolts. Any loosening of mount bolts, mounting plates, or head stays – is bound to cause an excess amount of vibration in the bike engine.
Loosening of engine mount bolts, mounting plates, or head stays happen due to repeated load and stress on the engine and not tightening it during the motorcycle servicing.
Such loosened mount bolts on the engine will cause an excessive amount of vibration, much higher than the normal engine vibration you will see while riding your motorcycle. That’s why, a high vibration in the motorcycle needs to be addressed as early as possible before it snowballs into something fatal.
The solution for loosened engine mount bolts, mounting plates, or head stays is to tighten and torque all the bolts to its specification. So, check for the loosened bolts and tighten them in order to reduce the vibration to its minimum.
In fact, you need to constantly check the bolts and screws specially related to that of the engine at regular intervals. All the mounting bolts should be tightened at every major motorcycle servicing. Or at least once in a year.
So, for preventive maintenance. Ask your mechanic to check and tighten the mounting bolts of the engine every time you take your motorcycle for servicing.
#2. Out of sync Carburetor
Another major reason why there is an excess amount of vibration in the engine can be an out of sync carburetor.
If the carburetor is not sending the air-fuel mixture at the right time to the engine, then the combustion cycle is not in alignment with the air-fuel entry into the combustion. As a result, the engine vibrations increase due to this out of sync arrival of the fuel mixture.
That’s why, an out of sync carburetor will not only cause excessive engine vibrations but also low fuel efficiency and exhaust popping as well.
The solution for an out of sync carburetor is straightforward. You need to synchronize the carburetor. Again, this is something that should be taken care of during a normal tune-up procedure.
Carburetor tuning should be done every time you take your motorcycle for servicing.
In carburetted motorcycles, the carburetor is the component mixing air and fuel to provide an optimum air-fuel mix to the engine. If the mixture is not at the right proportion, then you will be faced with low mileage problems.
So, tuning and synchronizing of the carburetor is an essential procedure that needs to be taken care of during motorcycle servicing. And that will easily address the problem of excessive engine vibrations in your motorcycle.
A word of caution. If there is an air leak, it can be a grueling task. Especially if the motorcycle has multiple carburetors. So, it is probably best to take the problem to a mechanic.
#3. Out of tune Engine
An out of tune engine is another cause for high amount of vibration coming from a motorcycle engine. An out of tune engine, be it single or multiple cylinders, will always run rough and vibrate heavily.
That’s why, it is essential for the engine to be generally in tune. Any lack of such tuning within the engine components, can cause overheating and excessive vibration in the engine.
The solution is again straightforward. The motorcycle needs to be taken for servicing and your mechanic needs to check up the engine components for their tuning. An out of tune engine, as stated earlier, will be damaging for the engine functioning in the long run along with its increased heating and vibrations.
You need to follow your owner manual’s recommended service intervals. Servicing your bike at regular intervals and at frequent times will go a long way in maintaining engine as well as the motorcycle in a good condition.
So, take your motorcycle for servicing and ask you mechanic to check the engine components and address the issues of out of sync engine components.
#4. Cracked Frame or Suspension
Another reason for increased vibration in the motorcycle engine can be because of cracked frame or suspension components in the bike.
This is more common in off-road motorcycles, but if your bike has sustained any accidents or damages recently, it’s worth checking for.
Anytime you feel a weird or undue vibration while riding the motorcycle which occurs after the bike has been in an accident, it may be due to damaged, bent, or cracked structural members of the motorcycle.
This isn’t something you want to take lightly, especially if the bike has faced an accident recently. If there are any bent on the forks or damages on the rim, the issue is quite serious and needs to be addressed immediately.
The vibration generating from the cracked frame or suspension members can be a symptom of a much fatal damage in the bike and if left unchecked, can prove fatal for the rider.
So, have your mechanic, someone you trust, inspect the frame and suspension components. It would be preferable if you can take your motorcycle to a shop that has experience dealing with accident-damaged bikes.
Ask the shop to check the frame and suspension components thoroughly and repair the damaged parts. If some of the compensate need to be replaced with a new one, do not fret over money and go with the replacement.
In order to reduce and control the excess amount of engine vibration in the motorcycle, check for any loosening of mounting bolts, synchronization of the carburetor, tuning of the engine, and for any damages in the frame and suspension components.
It is better to take your motorcycle to a trusted service shop to address these issues since ignoring or deferring them might lead to further damages or can even outright be fatal for the bike rider.