Kawasaki Vulcan 750 Problems, Signs & Solutions

Kawasaki Vulcan 750 ruled the mid-budget cruiser bike market with its 749CC V-Twin engine, excellent suspension system, and brilliant fuel efficiency at 45-50 MPG. Hence, people still crave owning the Vulcan 750 as a prestigious collectible. 

However, you should learn about Kawasaki Vulcan 750 problems before getting one. Even if you don’t ride the classic cruiser, knowing its problems would help you maintain it better. Also, you will learn how the actual riders felt about the motorcycle. 

Common problems of Kawasaki Vulcan 750 include quickly wearing out the cam and timing chain tensioner, engine overheating, and overcooling. You may also see the gear system and clutch failure sooner than expected. Hence, you must observe Vulcan 750 and troubleshoot the problem to ensure the best performance from the crowd-favorite cruiser. 

Kawasaki Vulcan 750 Feature and Specs: 

From engine details to dimensions and performance figures, the Kawasaki Vulcan 750 boasts iconic performance. Also, this overview will provide you with essential information about the Vulcan 750, whether you’re a proud owner or considering it as your next ride.

Kawasaki Vulcan 750 features and Specification	Details
Production Years	1985 – 2006
Engine	749cc V-twin
Transmission	5-speed, constant mesh
Cooling System	Liquid-cooled
Fuel System	Carbureted
Front Suspension	Telescopic fork
Rear Suspension	Twin shock absorbers
Front Brake	Single disc, dual-piston
Rear Brake	Drum
Weight	496 lbs (225 kg)
Fuel Capacity	3.6 gallons (13.6 liters)
Seat Height	30.9 inches (785 mm)
Wheelbase	62.2 inches (1580 mm)
Tires (Front/Rear)	100/90-19 / 150/90-15
Maximum Power	66 hp (49 kW) @ 7,500 rpm
Maximum Torque	47 lb-ft (64 Nm) @ 6,000 rpm
Compression Ratio	10.3:1
Top Speed	Approx. 115 mph (185 km/h)
Fuel Efficiency	40-50 mpg (city/highway combined)
Front Suspension Travel	5.9 inches (150 mm)
Rear Suspension Travel	4.1 inches (105 mm)

Kawasaki Vulcan 750 Problems And Solutions 

The Kawasaki Vulcan 750 was a powerful and comfortable cruiser. However, during its presence in the market, riders faced issues with its engine heat control, gear failure, and cam chain tensioner. You need to know about these Vulcan 750 reviews and problems for safe rides. 

Problem 1: Engine Overheating and Overcooling

Kawasaki Vulcan 750 engine overheating and overcooling issues relate to frequent irregularities in the motorcycle’s temperature regulation system. The standard motorcycle temperature should typically be around 150F to 230F (65C to 110C). 

Nonetheless, when the engine overheats, it operates at temperatures beyond the normal range. Many riders have reported that the engine temperature reached 250F, potentially leading to damage. Also, for many, sitting on the motorcycle comfortably was unbearable due to the excessive heat generation from the engine. 

Conversely, Vulcan 750 overcooling results in the engine running too cold. It impacted the performance and combustion efficiency. Also, at colder times, riders needed help in starting the engine. It happened mostly when they didn’t use the Vulcan 750 for a long time. 

Signs of engine overheating:

• The most evident sign of engine overheating in Vulcan 759 is a rising temperature gauge on the instrument cluster. It indicates that the engine is operating at higher temperatures than it should.
• An overheating engine may cause coolant leakage. Hence, you can see coolant leaking from the tank. Also, it may result in puddles of coolant beneath the motorcycle. The leakage is due to excessive pressure or compromised cooling system components.
• You may hear audible engine knocking or pinging sounds as the engine temperature increases. These sounds occur due to pre-ignition or detonation that the high temperatures within the combustion chamber create. 

Signs of overcooling engine:

• You will face difficulty starting the engine, particularly in cold weather. When the engine is too cold, the combustion process is less efficient. Thus, it gets harder to ignite the fuel-air mixture.
• Over cooled engines will mostly produce reduced power output. You will notice the power reduction, especially during acceleration and higher RPMs.
• Overcooling may result in the emission of excessive exhaust smoke. Hence, you may particularly see white smoke emitting from the exhaust. White smoke indicates incomplete combustion due to the engine running too cold.

Solutions to engine overheating and overcooling problems in Vulcan 750:

When your Kawasaki Vulcan 750 overheats, you must check and fix the reasons ASAP. It includes proper checking of the coolant, thermostat, and airflow of the motorcycle. 

• Check Coolant Level: First, ensure the motorcycle’s coolant level is at the recommended range. You can check it with a coolant dipstick. If the coolant level is too low, fill the reservoir with the appropriate coolant mixture if necessary. You should change the coolant once every two years or 20000 to 25000 miles. 
• Radiator Inspection: You should regularly inspect the radiator for clogs or damage. A clogged radiator reduces heat dissipation, contributing to overheating. So, you must clean or replace the radiator as needed.
• Thermostat Examination: Next, you may verify the thermostat’s functionality. A stuck closed thermostat will restrict the coolant flow. So, the engine won’t receive necessary coolant and overheat. You need to replace the motorcycle thermostat to overcome the problem. 
• Airflow Maintenance: Ensure there is unobstructed airflow around the engine. You should remove debris, dirt, or foreign objects that may block the cooling fins or obstruct airflow. Also, you can use a larger air filter and carburetor and clean the older ones for better airflow. 

Besides the engine overheating problem, the Kawasaki Vulcan 750 may also have overcooling issues. As it happens, you must check the thermostat. It should not be stuck open. A thermostat stuck in the open position can lead to overcooling. Also, consider using a lower-temperature thermostat.

Next, look for leaks in hoses, connections, and the radiator. When you find any coolant leaks, repair them with adhesive to prevent further cooling issues.

Problem 2: Cam And Timing Chain Tensioner Wearing Out Soon

Premature cam chain tensioner wear is a common concern for Kawasaki Vulcan 750 owners. This issue pertains to the cam and timing chain tensioner, which maintains proper tension in the timing chain that controls valve timing.

Ideally, the cam chain tensioner should last for 80000 to 120000 miles. However, a few riders have reported that their Vulcan 750 cam chain tensioner wore out at around 50000 to 60000 miles. So, it becomes tense with the faster wearing out of the timing chain tensioner. The engine may damage or fail completely as the time chain tensioner completely wears out or comes out. 

Signs of wearing out cam and timing chain tensioner:

• A clear sign of cam chain tensioner wear is a noticeable ticking or rattling noise from the engine. The noise is particularly pronounced at idle or during low-speed riding.
• As the cam chain tensioner wears out, it may fail to maintain proper tension in the timing chain. It will reduce engine power and acceleration, especially noticeable at higher RPMs.
• You will have a hard time starting the engine. The engine may not even start when the tensioner belt comes, or its teeth get damaged. 
• The “Check engine light” will illuminate. As it happens, you should immediately check the chain tensioner for damages. 
• Lastly, the engine will vibrate when it is idle. So, the motorcycle may shake, and the engine will become sluggish, too. 

Solutions to faulty cam chain tensioner 

One effective solution is to replace the stock cam chain tensioner with an upgraded aftermarket unit. Aftermarket Kawasaki cam chain tensioners such as the Cam Chain Tensioner For Kawasaki Vulcan 750 are a great option. It is designed with more robust materials and better tension control for improved longevity.

Nonetheless, you should also focus on preventing premature wear of the cam chain tensioner with proper maintenance. Hence, you should inspect and adjust the cam chain tensioner’s settings periodically. You will get the cam chain tensioner adjustment kit to tighten the belt. 

Adjustments may be necessary after 5,000 to 10,000 miles or extended use. It ensures that proper chain tension is maintained and will preserve the engine performance, too. 

You can change the old ACCT of the Kawasaki Vulcan 750 to the latest MCCT. For this, you may see the following YouTube video:

Problem 3: Faulty Clutch and Gear System

The clutch and gear system on the Kawasaki Vulcan 750 may develop problems over time. It will affect the motorcycle’s shifting and overall riding experience. Many riders reported that the gear transmission feels slugging, hard, or clunky. It happens especially when you shift from Gear-1 to Gear-2, which leads to a jerky and bumpy riding experience. 

Also, the clutch failure results in unsmooth acceleration. Your engagement and disengagement will become problematic when the clutch fails, leading to clunky gears. 

Signs of faulty gear and clutch

• A common issue for gear failure is the difficulty in shifting gears. You will notice it particularly when the engine is hot when you ride for 50 to 100 miles at a stretch. The gear changes may feel notchy, or the transmission may resist shifting.
• You will experience a lack of power during acceleration, with the clutch slipping out of its position. The engine’s power doesn’t effectively transfer to the rear wheel when the clutch slips. It will result in reduced engine performance.

Solutions to faulty gear and clutch:

The gear failure or slipping clutch can be problematic for the Kawasaki Vulcan 750. So, you should focus on clutch cable maintenance. You must observe the clutch cable’s tension and lubrication. The clutch won’t engage accurately if the gear and clutch lubrication is dry. The clutch and throttle lube will reduce friction and improve smoother engagement for the gear. 

• You need to disconnect the cable from the motorcycle first. 
• Then, choose the proper clutch cable lubricant on the clutch and gear cable. 
• Afterward, you should attach a funnel with a cloth or plastic to the cable’s top. 
• As you pour the lubricant through the funnel, it will reach the entire cabling. Then, you should attach the cable in its position. 

Besides lubricating the cable, you should periodically inspect the clutch plates and springs for signs of wear or damage. Worn components can lead to clutch slippage and gear engagement issues. So, when the clutch plate and springs wear out, replace them at a motorcycle mechanic shop. 

Next, you should check the clutch lever to determine if it is adjusted correctly. Proper adjustment ensures the appropriate amount of free play and engagement. An incorrectly adjusted clutch lever can lead to gear-related problems. Luckily, you can use the toolkit of your motorcycle to adjust the clutch lever for smooth gear shifting. 

Problem 4: Excessive Smoke and Exhaust

Excessive smoke and unusual exhaust emissions are often common Kawasaki Vulcan 750 problems. It can be indicative of underlying engine issues on the Kawasaki Vulcan 750. There can be white, brown, or black smoke coming from the engine and exhaust system, depending on the source of the problem. 

Typically, smoke comes out due to a damaged piston oil ring, worn-out valve guide and seal, clogged air filter and cleaner, higher fuel level in the carburetor chamber, etc. You may also see smoke due to missing air cleaners and clogged exhaust systems. 

Signs of smoke and exhaust failure:

• You will see thick and colored exhaust smoke. Excessive smoke from the exhaust, especially if it’s blue, black, or white, is a clear sign of a problem. Each color corresponds to different issues: blue indicates oil burning, black suggests a rich fuel mixture, and white signals coolant or water vapor entering the combustion chamber.
• You will notice an unusual exhaust smell or noise during the operation. It suggests combustion-related issues. These issues may result from improper fuel mixture or incomplete combustion.

Solutions to excessive smoke of Vulcan 750

Oil leaks are often responsible for blue smoke emission from Kawasaki Vulcan 750. Hence, to combat blue smoke, inspect the engine for oil leaks. During inspection, focus on seals and gaskets. Replace any worn or damaged piston or valve seal to prevent oil from entering the combustion chamber.

Inspect the carburetor or fuel injection system if the exhaust emits black smoke. Ensure proper calibration and adjust the air-fuel mixture as necessary. It is essential to achieve optimal combustion and reduce emissions. Also, if the carburetor’s fuel level is too high, it causes black smoke emission. You must maintain the fuel level to stop this. 

Air filter and spark plug maintenance are crucial to stop the Vulcan 750 engine smoke emission. You should regularly clean or replace the air filter to address rich fuel mixtures. An adequately maintained air filter ensures proper airflow to the engine. So, the fuel mixture will be proper, which ensures better combustion and ignition.

Additionally, replace worn-out spark plugs for every 20000 to 30000 miles. A cleaner spark plug ensures better ignition to reduce smoke emissions. 

Problem 5: Slugging Engine and Starting Difficulty

You may face difficulties, including hard starts and engine failure to start. All these can be frustrating issues for Kawasaki Vulcan 750 owners. The motorcycle’s reliability will drop if the engine fails or becomes sluggish. 

Also, these could suggest a complete engine failure. So, you must be careful to observe if the engine fails or it gets hard to start. 

Signs of engine failure:

Does the motorcycle require frequent use of the choke during startup? It may be especially necessary in colder weather. Thereby, it indicates difficulty in achieving proper fuel mixture and ignition.

Also, the starter motor will begin to spin without engagement. Hence, when the starter motor spins but doesn’t engage with the engine, it prevents the motorcycle from starting. Moreover, it may be caused by a faulty starter clutch or related components.

Solutions to engine sluggishness and starting difficulty:

As you experience difficulty starting the engine, first check the battery. It should be in good condition and fully charged. If the battery is damaged or leaked, you can replace it with the YTX14AHL-BS Motorcycle Battery for KAWASAKI VN750-A Vulcan 750CC 86-’06

Next, you should clean and tighten all electrical connections to ensure a consistent electrical flow. On top of that, you must inspect the starter solenoid and starter clutch for wear, damage, or malfunction. The solenoid connects the battery point and the motorcycle starter. If the solenoid goes bad, you must replace it. 

Lastly, clean and synchronize the carburetors. It will deliver a balanced fuel to the engine’s cylinders. Adjust the idle speed and air-fuel mixture to achieve smooth and reliable starts.

Conclusion 

Kawasaki Vulcan 750 problems are nominal compared to its outstanding performance and features. Although Kawasaki stopped producing its 3006, the Vulcan 750 remains one of their most popular cruiser models. 

It is an excellent motorcycle with easy maintenance and incredible performance. You should use proper lubricant, change the worn-out spark plug solenoid, and take care of the engine to avoid the problems of the Kawasaki Vulcan 750. And with it, the Vulcan 750 has become an excellent collectible for all motorcycle enthusiasts.