Troubleshooting an ATV that won’t go into gear or won’t shift gears can be quite complicated, but not always. Whether you’ll be able to address the issue on your own depends on the severity of the problem as well as your mechanical skill level.
ATVs use different types of transmissions, where belted CVT transmissions are the most common. The possible causes and the steps required to solve the problem depend on the type of transmission your ATV has.
This post covers some of the most common causes if your ATV doesn’t go into gear. It is meant to guide where you should begin your troubleshooting but not as a complete repair guide for all types of ATV transmissions.
The service manual for your specific brand and model will provide more detailed troubleshooting procedures for your transmission issues.
Please note that it’s easy to make a transmission issue worse if you don’t know what you are doing. Some of the repairs require special tools such as a clutch puller or a clutch disassemble tool. If the repair seems intimidating to you or you do not have the right tools, it is recommended that you take the bike to a dealer technician.
Step 1: Does the ATV shift gears as normal with the engine off?
We recommend that you begin the troubleshooting by testing whether you can shift gears when the engine is not running. This initial test allows you to narrow down the possible culprits of your gear shifting issue.
If you can shift gears with the engine off, you know that the gear shifting mechanism, as well as the inside of the gearbox, most likely works fine.
Gear shifting problems that are only present when the engine is running are usually clutch- or belt-related (Step 3) or caused by a high idle (Step 2). You may find that the bike wants to creep or move forward when in gear at idle. But even without creep, the problem may be with one of these components.
If you are, however, unable to shift gears with the engine off, we recommend you jump straight down to Step 4.
Step 2: The idle is set too high – causing the clutch to engage
Many ATVs come with an automatic clutch that engages when you apply throttle, and the clutch speeds up. The same principle applies whether you have a wet disc clutch or a dry clutch as you find on a belted CVT transmission.
If the ATV, for some reason, idles higher than it’s supposed to, it may cause the clutch to engage slightly, putting a small but constant tension to the metal gears inside the gearbox. This pressure on the gears makes the ATV very hard to shift.
Most ATVs should idle around 1100-1200RPM. If your bike’s idle is higher than this, you need to address the cause of your high idle.
For carbureted ATVs, there will be an adjustment screw to set the idle. Your user manual will provide the correct setting for your bike. Adjusting the idle on a fuel-injected ATV is usually a job for a mechanic.
Step 3: The CVT is engaging too soon or not disengaging properly
When idling, the primary clutch on a belted CVT transmission is supposed to spin freely without engaging (not pulling on the belt). This relieves the tension on the gearbox and allows you to shift gears.
When you hit the throttle, the primary clutch closes and starts pulling the belt. The belt makes the secondary (driven) clutch spin, which creates tension between the gears inside the gearbox.
This is how a CVT transmission works:
But when the transmission is not tuned correctly or has a mechanical issue, it may be engaging and spinning the secondary clutch even at idle.
To troubleshoot an issue like this, you need to remove the belt cover to inspect the clutches and see how they behave when the engine runs, both at idle and when revving in neutral.
Please note that the clutches will be spinning at high speeds. Keep your hands and all loose objects clear of clutches to avoid potentially fatal damage.
Cause 1: The clutches are dirty
If the primary clutch is packed with dirt, it may bind or not open enough to release the belt. Now is a good time to pull the clutches for proper cleaning and service.
Cause 2: The clutch spring is getting weak
The springs inside a CVT transmission clutch may weaken over time, preventing the clutch from functioning as it is supposed to. Clutch springs are replaceable, but you may need special tools to pull and disassemble the clutch.
Cause 3: The clutches are not aligned; a bad or loose engine mount
If the motor mount is bad or has come loose, the primary clutch may be out of alignment. Use a pry bar to see if you can lift the whole engine. You should barely be able to see the engine move, if at all.
Cause 4: The clutches are not aligned; the belt is offset (common issue)
The drive belt should ride in the clutch assembly center, not touching the primary’s two clutch sheaves. If it does rub against one of the sheaves, it will cause unwanted tension on the belt.
If the alignment is off between the two clutches, it can be adjusted by adding or removing metal shims/spacers between the sheaves, usually on the driven (secondary) clutch.
Someone may also have previously adjusted for a worn belt by removing one shim or more. When installing a new belt, you may need to add those spacers back to prevent binding, leading to gear shifting issues.
Cause 5: Worn drive belt
If the drive belt is worn too much, it will ride low on the sheaves, causing a slight creep.
Cause 6: Using an aftermarket drive belt
We recommend that you only use OEM belts. There are aftermarket belts available that offer better performance and longevity at a smaller price. But slight variations in production tolerances can cause issues such as the clutch engaging too soon.
Aftermarket belts also use a harder compound to make them last longer, which may wear your clutch sheaves over time.
Cause 7: Shredded drive belt
Remove the belt cover. If the belt is shredded, it may have gotten wrapped around the driven shaft, causing it to bind up.
Cause 8: Worn EBS washers (common issue)
Polaris ATVs with EBS (engine brake system) have components that may wear out in time. Inspect the EBS fiber washers (one on each side of the EBS bushing) on the primary clutch to see if they are worn out. If the washers are worn, the belt may not ride in the grooves as it should and instead ride one of the sheaves.
Cause 9: Bad one-way bearing
Some ATVs with engine brake systems have a primary clutch with a one-way sprag bearing, a so-called one-way clutch. It is supposed to spin freely in one direction and be locked in the other direction. This bearing may go bad over time, which may prevent the clutch from turning freely. It may be hard to tell if the bearing is ok; just a slight drag may cause shifting issues.
Step 4: The ATV won’t shift gears even when the engine is turned off
In this case, the problem is likely with the gear changing mechanism or the transmission’s internals. Begin by troubleshooting the externals as they are the most accessible.
Cause 1: Gear linkage is worn or out of adjustment
Some ATVs have adjustable gear linkage. If not adjusted correctly, the bike will not shift as it should.
How to inspect and adjust the gear linkage:
- Make sure the ATV is in neutral.
- Remove the linkage from the shift box.
- Inspect the bellcranks to make sure they are not stripped or have split.
- Inspect the ball-ends for wear.
- Replace any damaged components.
- Set the gear shifter to neutral.
- Adjust the ball ends until they drop straight onto the shifter.
Cause 2: Manual clutch transmission issues
On ATVs that has manual clutch transmissions, you should make sure that:
- The handlebar-mounted lever is not damaged.
- The cable is not broken.
- The cable does not need adjusting.
Cause 3: Internal gearbox issues
To test your gearbox for internal damage without splitting the case you can try this method:
- The engine should be off.
- Remove the belt cover.
- Remove the drive belt.
- Shift the bike into gear.
- Try manually rotating the primary clutch; the bike should move.
- If the bike does not move, you likely have an issue inside the gearbox.
Cause 4: Wore or bent shift fork
One of the most common issues one could be facing with a gearbox’s internals is having a worn or bent shift fork. The shift fork is what shifts the gears in place. If it is bent or worn, it can’t push the gears completely in place.
Step 5: Wet clutch or hydrostatic transmission issues
Some ATVs use an oil-sump wet clutch in combination with the dry clutches on the CVT belt transmission. You also have some Honda ATVs with hydrostatic transmissions that use oil to drive the ATV forward.
Here are a few things to check out whenever any of these types of ATVs won’t go into or shift gears.
Cause 1: The oil level is low
Make sure the oil level is correct or the bike may not shift as it should.
Cause 2: The oil needs replacing
If the oil is old or contaminated it needs replacing:
- Drain the old oil into a drain pan.
- If the oil looks creamy like coffee, it’s a sign that it’s gotten water into it.
- If the oil is black and smelly, it’s old and long overdue for replacing.
- Also, look for debris such as old seals being drained out with the oil.
- Add new oil to the correct level. Make sure it is according to spec.
- Let the bike run for 10 minutes.
- Change the oil once more.
- This final time, also change the oil filter.
Cause 3: The oil is not moving correctly through the engine
It is possible to measure if the oil moves well through the engine using an oil pressure gauge. If the pressure is weak, you may have bad seals and need to open the engine.
Step 6: Honda ES electric shift transmissions: shifter motor issues
ATVs with an electric shifter, like the Honda AS models, uses an electric motor to shift through the gears. If the motor does not work, the bike will not shift gears.
The only way to make it shift is by using the emergency shifter (a short-shifting shaft sticking out the left lower side of the engine, use the supplied gear change tool). If the bike shifts when using the emergency shifter, you need to address the shifter motor.
Cause 1: The motor is wet
If the ATV has been submerged in water, you need to make sure all of the water is drained from the shifter motor.
- Remove the motor and give it a proper cleanse with an electric-cleaner.
- Let it dry and re-grease it with dielectric grease.
- Hook up the motor to a 12V battery to test it before reinstalling.
- Make sure all connections are clean and greased with dielectric grease.
Cause 2: The motor is burnt out
Remove the motor. If the motor does not turn even when hooking it up directly to a battery, it may be burnt out and need replacing.
Cause 3: The battery is not adequately charged
It is easy to forget that an electric-shift ATV needs electricity to shift. Make sure the battery is properly charged and in good condition.
Cause 4: Too heavy or gummed up grease in the shift motor gears
If you try to shift on an electric shift ATV, you may hear the shift motor moving, but it does not shift completely.
You may find that the problem is worse at colder temperatures. Fixing this issue is relatively easy. All you need to do is replace the old gummed-up grease with all-temperature, white lithium grease.
For the complete procedure, go to Hondaatvforums.net
Cause 5: Bad angle sensor
Located on the carburetor, the Honda ES models have an angle sensor that tends to go bad. After replacing the sensor, make sure it is clocked correctly.
Step 7: The ATV won’t shift into gear or into neutral without rocking it back and forth
When this happens, there is usually no need to worry. In fact, most ATVs are affected by this issue, some more than others.
What happens is that the wheels must be rotated slightly for the gears inside the gearbox to sync (line up).
You may have noticed that this phenomenon gets worse when trying to shift in and out of “park” when standing on a hill.
The best way to avoid this is by applying the parking brake before putting the transmission in “park.” This way, the gears won’t bind up, and you will be able to shift in and out of gear effortlessly.