8 Common Husqvarna FC350 Problems (Explained)

The Husqvarna FC350 is a popular motocross bike offering a perfect balance of power and agility.

The FC350 features a 350cc four-stroke engine, a lightweight steel frame, a hydraulic clutch, and a customizable engine map switch.

But like any motocross machine, the Husqvarna FC350 is bound to experience issues from time to time.

This article explores the most common problems with the Husqvarna FC350, including testimonials from real-life owners and how to troubleshoot them.

1. Electric Start Problems

Some Husqvarna FC350 Owners have experienced issues with the electric start button not turning over the motor fast enough or draining the battery faster than what’s typical for these bikes. Potential culprits include short circuits, faulty needle bearings, or bad wiring connections.

“fc350 3017 that I just rebuilt… When I press the electric start button, it won’t turn over the motor very fast, and it will only do 3-5 rotations before it stops. Then I have to press it again just for it to turn over one more time. I bought a new battery, and it still won’t work properly! It also drains the battery super-fast, as in, I get about 30 seconds of turnover time tops. The battery also gets very hot and steams when I hold the starter button for too long. Any ideas on what it could be? I cleaned connections, so I don’t believe that’s the problem.”

Solution:

Check the battery voltage and connections. Make sure the battery is fully charged and not damaged. Inspect the starter motor and solenoid for any signs of wear or short circuit.

Check the needle bearing on the starter gear for any damage or seizure. Examine the wiring harness and fuses for any shorted, loose, or broken wires. Replace any faulty parts as needed.

2. Restricted Airbox

Owners often report that the plastic air intake unit on the Husqvarna FC350 is known to be restrictive to the air intake flow due to its small size. A small airbox limits the workflow and, therefore, the engine performance of the FC350.

Riders report replacing their FC350’s airbox with an aftermarket unit or cutting holes in the stock unit to increase air intake.

“I purchased a 2017 FC350 this year and was lucky enough to pick Dave Feeney’s brain (Rockstar Husqvarna mechanic for Zach Osborne) about airbox mods, he suggested cutting the battery box back to allow more air to flow in through the air inlets at the back. Even though they still have their side plates, he said they often tape them up on a wet track, so it wasn’t super critical. He suggested opening up the exhaust system to allow more air.”

Solution:

Remove the airbox cover and see if you notice any performance improvement.

If yes, drill some holes in the airbox cover, following instructions provided by a knowledgeable mechanic, either online or in person. Otherwise, consider replacing the stock airbox with an aftermarket one.

If removing the airbox cover didn’t improve your engine performance, check the TPS voltage and adjust it if necessary.

Check the air filter and replace it if dirty or clogged. Inspect the reed valves inside the airbox and remove them if they restrict airflow.

3. Harsh Fork Suspension

Riders report the Husqvarna’s WP XACT Air Forks to feel too stiff or harsh on small bumps, especially at low speeds. Harsh suspension affects the comfort and handling of your motocross ride. Some owners adjust their air pressure, compression, or damping; others switch to coil-spring forks.

Solution:

Inspect the air pressure in the forks and adjust it according to your weight and riding style.

Check the compression damping and rebound damping settings, adjusting them to your preference.

Examine your fork oil level and change it if it is too low or too old. If none of this help, consider getting a re-valve or a spring conversion kit or replacing your FC250’s forks.

4. Lazy Gearing

The stock gearing on the Husqvarna FC350 is 14/51. Some owners complain that this gear ratio makes the bike feel sluggish, particularly on the low-mid range transition. Some riders report that changing their rear sprocket to a size 52 or 53 improves acceleration.

“The Husky is similar in that it likes to be ridden aggressively, but it behaves differently. I want to say that I would like a little more snap right off the bottom, but I could clear jumps out of corners and didn’t fight the bike at all. I thought the muffler might add a tad bit of snap, as mentioned before. Or 1-tooth to the back might be something to consider, but I don’t want to lose that pull in 2nd gear, which seems to pull forever. I was there with my friend (the son of the dealership owner where I bought the bike), and he is an A-rider on the same bike. He says I just need to adjust to the riding style, maybe the muffler, but otherwise, leave it alone.”

“The stock gearing is too tall for my liking. It makes the bike feel slow and boggy on the low end. I switched to a 52-tooth rear sprocket, which made a huge difference. The bike pulls harder and faster out of corners and has more snap.”

Solution:

Check the sprocket sizes and chain condition on your bike. If the sprockets are worn or damaged, replace them with new ones.

If you want to improve the acceleration and snap of your bike, go for a larger rear sprocket or a smaller front sprocket.

Conversely, to improve your bike’s top speed and fuel economy, go for a smaller rear or a larger front sprocket.

5. Weak Clutch Action

The Magura hydraulic clutch on the FC350 reportedly fades or slips under heavy use or aggressive riding, especially in hot or dusty conditions. Some owners upgrade their clutch springs, plates, or master cylinder to a more durable or responsive setup.

Solution:

Check the clutch lever free play and adjust it if necessary. Inspect the clutch fluid level and condition and bleed or change it if needed.

Examine the clutch plates, springs, and basket for any signs of wear or damage. Replace them with new ones if they are worn out or slipping.

If you want a more robust clutch, go for a heavier-duty clutch kit.

6. Fuel Pump Issues

Some Husqvarna FC350 owners have reported problems with the fuel pump failing or leaking, causing the bike to lose power or not start.

Some riders report that dirt, water, or ethanol-laced fuel was present in the fuel system, causing the fuel pump failure.

This indicates that, while fuel pump failure isn’t the fault of an issue with the pump itself, the fuel system in the FC350 is susceptible to contamination and sensitive to ethanol.

However, in other cases, riders report that the wiring to the fuel pump was frayed, shorting out their Regulator/Rectifier in the process.

Finally, another theory regarding the FC350’s fuel pump issues is that the seat shreds the Regulator/Rectifier due to faulty wiring positions. The frayed R/R wires then short out the fuel pump.

“I was riding the bike, and it stopped and hasn’t started since; no FI light flashing, and the fuel pump was dead. 2 wires to the fuel pump relay had worn through the plastic, but these are now fixed, and still no luck…. There are a few people who seem to have had this problem.”

“I had the original [fuel pump] go bad after about 20 hours. The dealer swapped the whole tank with a 500, and I got 140 hours now. I think the filter is getting clogged up. I figured I’d order a whole pump and filter and put that in.  I’ll keep the OEM one as a spare, but I hear the quantum ones are better.”

“I had the seat pushed (pinched) on the white wire that goes to the volt reg on my Husqvarna because the wires were routed wrong. I told my dealer, and he said he had three on the floor that were wrong. On the front right corner of the seat is where it was. If you take the seat off and look, the wires go into a channel in the plastic subframe. Mine were routed underneath it and rubbing.”

Solution:

Check the fuel quality and freshness in your tank. Drain any old or contaminated fuel and replace it with a fresh one.

Inspect the fuel filter and hose for any dirt, water, or ethanol buildup and clean or replace them if needed.

Check the fuel pump for any cracks, leaks, or malfunctions and replace it if needed.

Inspect the wiring under your seat and see if the R/R or fuel pump’s wiring is trapped, frayed, shorting out, or causing electrical damage. Replace damaged wiring and blown fuses as needed.

7. Engine Overheating

Some Husqvarna FC350 owners have reported problems with the engine overheating, causing the bike’s engine to lose power and its coolant to boil over.

Some riders report that riding in slow technical terrain or on hot days was the leading cause of overheating, as the bike can’t get enough airflow to cool down the radiator and the engine.

The limited air intake space we addressed in the first section indicates that the FC350 engine is sensitive to heat and requires adequate ventilation and coolant circulation to prevent overheating.

“Picked up my first husky about a month ago now. I love this bike! I was doing technical riding a couple of weeks ago using the clutch a lot, and the bike started to boil over. I have read that if fc/fx350 and 450 models do not get enough airflow, they will overheat. I was thinking about reprogramming the ECU to help with the overheating and flameouts.”

“Get a Trail Tech fan and call it a day. I had to do the same on my FX350. They don’t like slow technical stuff. They will get hot.”

Solution:

Check the coolant level and quality in your radiator. Top up or flush your coolant if needed. Inspect the cooling system for any leaks, cracks, or blockages and repair or replace them if needed.

Install a fan kit to increase the airflow over the radiator and cool down the engine, especially when riding in slow or technical terrain.

Reprogram your ECU to optimize your fuel mixture and reduce the risk of overheating and flameouts. Use your clutch wisely to control your engine speed and power delivery and avoid overheating or stalling.

8. Map Switch Issues

Some Husqvarna FC350 owners have reported issues with the map switch, which is a device that allows you to change the engine settings for different riding conditions. The map switch affects the ignition timing and fuel injection, which can alter your FC350’s engine power delivery and behavior.

The Husqvarna map switch has two positions: standard and advanced.

The standard position is the default setting that provides a balanced performance for most riding situations.

The advanced position is a more aggressive setting that provides more power and responsiveness for faster or more technical riding.

Some of the common problems with the Husqvarna map switch FC350 owners have reported experiencing include:

• The map switch is not working correctly or not making any noticeable difference in the engine.
• The wiring of the map switch is frayed or damaged, causing electrical issues or short circuits.
• The map switch is affected by water or dirt, causing corrosion or malfunction.

Some owners replace the Husqvarna map switch with the aftermarket Trail Tech map switch, which is a device that offers more options and flexibility in changing the engine settings.

The Trail Tech map switch has three positions: standard, mild, and wild.

The standard position is the same as the Husqvarna standard position. The mild position is a softer setting that provides less power and smoother throttle response for easier or slippery riding.

The wild position is a more extreme setting that provides more power and sharper throttle response for faster or more aggressive riding.

“I have the trail tech switch with the kill switch combo. I’ve been running mine for 40 hours, 1250 miles trouble-free so far…”

Solution:

If you have problems with your map switch or want to upgrade your engine settings, consider replacing your Husqvarna map switch with a Trail Tech map switch.

Check your wiring and connections for any damage or corrosion and repair or replace them if needed.

What Are the Pros and Cons of the Husqvarna FC350?

Pros:

• Balanced power
• Lightweight handling
• Hydraulic clutch
• Map switch options
• Electric start
• Air forks adjustability
• Gearing flexibility
• Fuel pump reliability

Cons:

• Soft suspension
• Restricted airbox
• Map switch issues
• Electric start problems
• Harsh forks
• Lazy gearing
• Weak clutch
• Overheating

What Do the Reviews Say?

“The broad but linear Husqvarna FC350 powerband enables the rider to get on the gas sooner, stay on longer, and make enough power on top to close the deal.”

“The 350 has the same strengths and weaknesses as the 250, which means it’s excellent at initiating turns, has very little squat under acceleration, and has a slightly harsh, stiff feeling chassis on hardpack tracks with chop.”

What Are Some Alternative Models?

What’s the Resale Value of the Husqvarna FC350?

Sources:

Husqvarna Fc 350 Motorcycles for Sale Near Me – Cycle Trader

Husqvarna FC 350 motorcycles for sale – MotoHunt

RIDING THE 2023 HUSKY FC450, FC350 & FC250: THE WRAP – Dirt Bike Magazine

FULL TEST: HUSQVARNA FC350 – Dirt Bike Magazine

MXA RACE TEST: THE REAL TEST OF THE 2022 HUSQVARNA FC350 – Motocross Action Magazine