The KTM 65 is a popular, competitive motocross bike for young riders between the ages of 8 and 12.
It has a powerful and responsive two-stroke engine, a lightweight and agile chassis, and various features and accessories to suit different riders and preferences.
In this article, we will look at some of the most frequently reported issues with the KTM 65 and how to fix or prevent them.
Whether you already own a KTM 65 or are thinking of getting one, this article will help you get the most out of your bike and avoid any unpleasant surprises.
Table of Contents
1. Clutch Problems
One of the most common problems KTM 65 owners report is clutch failure. Riders report clutch slippage and faulty clutch engagement, sometimes resulting in difficulty shifting gears and power loss.
The clutch is the vital component that changes gears and manages the power delivery from your engine to your rear wheel.
“My ktm 65 sx clutch won’t disengage. If you start the bike and shift with the clutch held, the bike dies instantly. If you push into it first and then begin to use the clutch normally, it seems to free up and work okay. When I look into the oil intake and pull the clutch, there is movement between the plates, but it doesn’t engage the engine drive.”
Therefore, faulty clutch action impacts the performance and safety of your KTM 65 dirtbike.
There isn’t a particular cause or defect with the clutch failures on the KTM 65, so the solution varies based on the following situations:
- Low fluid level: Your clutch master cylinder on the handlebar and may not have enough fluid. If not, top it up with the recommended type of fluid.
- Worn or damaged clutch plates: Your clutch plates could be worn or damaged from improper oil levels, shifting, or from debris. If they are worn out, replace them with new ones.
- Ridges on the clutch basket: Your KTM 65’s clutch basket could have ridges cut into it by the steel plates. If there are deep ridges, file them away or replace the basket.
2. Faulty Jetting and Carburation
Another issue common to the KTM 65 is faulty jetting and carburation. Your dirt bike’s carb system determines how much air and fuel are mixed and delivered to the combustion chamber.
Therefore, if the carburetor or its jets are impaired, your engine’s performance can dip, causing poor idling, fouled spark pugs, and stall outs.
“The stock jetting is on the rich side for summer, and the KTM 65 and the stock Mikuni are very sensitive to changes in temp and altitude. The bike needs an air screw adjustment basically every ride, and it doesn’t help that the air screw is very hard to access.”
“[My 2017 KTM 65] will start up but does not want to idle. Every time I come to a stop after riding, it wants to shut off immediately.”
Fortunately, there are some easy solutions that you can try to fix the annoying jetting and carburetion issues, depending on the cause:
- Wrong jet size: Your KTM 65’s jets may not match the recommended one for your altitude and temperature. If it is too big or too small, replace it with the correct one.
- Dirty carburetor: Take off the carburetor and clean it thoroughly with carb cleaner and compressed air. Make sure to clean the jets, the float, the needle, and the air screw.
- Misaligned float: Ensure your float height is adjusted according to the manual. A misaligned float can cause a high or low fuel level in the bowl, which can affect the jetting.
- Wrong spark plug: Your spark plugs may be the wrong spec, type, or heat range for your KTM 65. An improper spark plug can cause fouling or detonation.
3. Faulty Stator
One of the most common causes of electrical failures on the KTM 65 is a faulty stator.
The stator is a coil of wires that uses engine power to generate electrical current.
The electricity is then used to power the ignition, lights, and other accessories. However, sometimes a stator wears out early, overheats, shorts out, or gets damaged.
If this happens, your KTM 65’s stator produces insufficient or erratic voltage.
“The stator provides electrical energy to the ignition. Every now and then, I’ve seen the KTM 65 stator go bad. You have to check it with an Ohm meter when it’s warm… If all the basics have been checked, I would check the coil and stator with an Ohm meter. You’ll have to get the Ohm specs from the manual.”
“My grandson’s… [KTM 65] bike looks good but has needed a lot of work: new crank bearings and seals, piston, and rings, carb rebuild, new carb boot, and numerous other little things. But the biggest problem was I could not get it to run for more than a minute. It turns out the stator tested bad, so I bought a new one and am ready to time it.”
- Your KTM 65’s stator may not be generating the proper resistance and continuity. Check it with a multimeter, following directions online.
- If your KTM 65’s stator isn’t producing the proper Ohms reading, replace it with a new one.
4. Ignition System Issues
Another common cause of electrical failures on the KTM 65 is ignition system issues.
The ignition system consists of the spark plug, the coil, the CDI box, and the wiring that connects them. The ignition system is responsible for creating and delivering a spark to the combustion chamber at the right time.
If any aspect of your KTM’s ignition system malfunctions, you’ll notice intermittent starting issues or a complete loss of spark.
“I’ve had a few problems with plugs fouling on the starting gate lately. The bike will run awesome for a while, and then all of a sudden will start fouling plugs. The plug looks fine and dry each time I remove it and starts the first kick when I install a new plug. I’ve changed the pilot jet to one step leaner and have tried air screw numerous times but doesn’t seem to clear it up.”
Some of the possible culprits of starting problems on a KTM 65 are:
- Faulty spark plug: Your KTM 65’s spark plugs may be worn or fouled. If it is dirty or damaged, replace it with a new one.
- Ignition coil failure: Check the coil for resistance and continuity with a multimeter. If it’s not generating resistance, replace it with a new one.
- Faulty CDI box: Inspect your CDI box for any signs of damage or corrosion. If you find any, replace it with a new one.
- Damaged wiring: Check your wiring for any loose, broken, or corroded connections. If you find any, repair or replace them as needed.
5. Suspension Needs Upgrades
While the KTM 65 is equipped with quality suspension components, some owners have mentioned the need for suspension adjustments or upgrades to suit their child’s body type or riding style.
Your KTM 65’s suspension is critical for proper performance, handling, comfort, and safety. Therefore, if your KTM 65’s suspension is too soft, unbalanced, or stiff, it makes a noticeable difference.
“I’m looking at buying a 2012 -2013 KTM 65 for my son to race next year. He will be too old for the 50’s. My son, like me, is extremely small for his age. He is only 49″ tall and only weighs 50 lbs. A 65 is really tall for him, he tiptoed on his KTM 50 SR. He is a very good rider but feels a bit awkward with the height when he rides his friend’s 65. What can I do to lower the bike to give him confidence and still keep it handling well?”
“Run softer and shorter springs with 3 inches sag and move the forks up in the clamps. If you want to spend the money, you can get the suspension set up for him. They should be able to lower it a decent amount internally. My brother really likes his Rekluse clutch in his 65, and it helps to teach them to use the clutch because if he misses it or anything, he’s ok, and it will keep the bike from stalling out.”
Fortunately, there are some easy solutions that you can employ to fix your suspension issues:
- Improper spring rate: Your 65’s spring rate may not be right for your child’s weight and riding style. If it is too stiff or too soft, replace it with the correct one.
- Improper sag setting: Your KTM 65’s sag setting may not be adjusted according to the manual. Sag is the amount of suspension travel that is used when you sit on the bike. Sag affects the geometry and balance of the bike.
- Wrong damping setting: Inspect the damping setting and adjust it according to your preference. Damping is the amount of resistance that the suspension offers to movement. Damping affects the responsiveness and smoothness of the suspension.
- Worn or damaged suspension parts: Your suspension parts may be worn or damaged. If you find any, replace them as needed.
6. Worn Chain and Sprockets
The chain and sprockets of your KTM 65s are responsible for transmitting the engine torque to the rear wheel.
However, some owners have reported that the chain and sprockets can wear out or get damaged prematurely and cause various symptoms, such as noise, vibration, or loss of power.
It’s important to note that regular maintenance of the chain and sprockets is essential to ensure smooth power transfer and prevent premature wear.
Furthermore, routine inspection and adjustment can help prevent your 65’s chain and sprockets from incurring wear and tear and from damaging surrounding parts.
- Improper chain tension: Chain tension may not be adjusted according to the manual. Chain tension is the amount of slack that the chain has when you push it up or down. Chain tension affects the alignment and wear of the chain and sprockets.
- Insufficient chain lubrication: Your KTM 65’s chain may not be lubricated to spec. Chain lubrication is the amount of oil or grease that the chain has to reduce friction and corrosion. Chain lubrication affects the smoothness and longevity of the chain and sprockets.
- Worn or damaged chain and sprockets: Your chain and sprockets may exhibit signs of wear or damage. If they are worn or damaged, replace them as a set. Chains and sprockets create a wear pattern with each other. When one component is replaced and not the others, the new component depreciates quicker because of the wear patterns developed on the other parts.
- Worn or damaged chain guide: Your KTM 65’s chain guide could be damaged from poor maintenance, rocks, or debris. If it is worn or damaged, replace it with a new one. A chain guide is a plastic or metal piece that guides the chain over the swingarm. Chain guide affects the stability and protection of the chain.
7. Overheating in Warm Climates
While this is by no means a widespread problem, small two-stroke engines like the KTM 65 may experience overheating in warm climates, particularly if the cooling system and engine oil aren’t maintained properly.
- Inadequate cooling or airflow: If the cooling system isn’t clean and free of debris, overheating can occur. Clean the radiator fins and the fan blades with compressed air or water. Make sure the fan is working properly and turns on when needed. Avoid slow or stop-and-go riding or high ambient temperatures.
- Improper jetting: Your KTM 65’s jetting may not be correct for your altitude and temperature. Jetting affects the fuel-air mixture and the combustion temperature. If the jetting is too lean, it can cause the engine to run hotter than normal. If the jetting is too rich, it can cause the engine to run poorly and foul plugs.
- Malfunctioning radiator: your KTM 65’s radiator could be damaged or clogged. The radiator is responsible for transferring heat from the coolant to the air. If the radiator is damaged or clogged, it can reduce the cooling efficiency and cause the engine to overheat. Replace the radiator if necessary.
What Are the Pros and Cons of the KTM 65?
- Powerful and responsive two-stroke engine
- Lightweight and agile chassis
- Adjustable and customizable features and accessories
- Hydraulic clutch
- WP suspension
- Brembo brakes
- Excel rims
- High maintenance
- Expensive parts
- Not street legal
- Short service interval
- Hard to find specific parts.
What do the Reviews Say?
“The 2023 KTM 65 SX benefits from the same development strategy as its bigger 2-Stroke brethren. Featuring everything the bigger motocross machines do, from a proper clutch and gearbox to the latest WP XACT. In fact, you’d be remiss to think this was anything less than a proper little READY TO RACE weapon.” –Total Motorcycle
“The adjustable WP Xact suspension can be tailored to meet the rider’s or track’s specifications. Maxxis knobbies provide grip, while four-piston calipers clasp wave brake discs. Powering this six-speed dirt bike is a 65cc single-cylinder two-stroke engine.” –Cycle World
“The KTM 65 gets a 64.9cc single-cylinder 2-stroke engine that offers class-leading power and torque. It comes with a fully manual 6-speed transmission that works in tandem with a hydraulic clutch unit. It features a pressure-controlled exhaust valve that improves performance.” –Bike Top Speed
“The KTM 65 SX is a fully-fledged piece of sports equipment for young pilots aged between 8- to 12 years old. This year’s top student features a revolutionary WP AER 35 front fork, ultra cool graphics, and sets the standard in terms of power, riding dynamics, equipment, and craftsmanship.” –Total Motorcycle
What’s the Resale Value of the KTM 65?
What are Some Alternatives to the KTM 65?
|Husqvarna TC 65