What To Do If Motorcycle Throttle Sticks: A Mechanic’s Guide


Because motorcycles are smaller than cars and much more basic, every component on them is very important. This includes the throttle. Without it, you wouldn’t be able to accelerate.

When a motorcycle throttle sticks, it can really give you an uneasy feeling. This is an issue that should be immediately addressed to ensure your safety and prevent any damage to your motorcycle.

What should you do if the motorcycle throttle sticks? When the motorcycle throttle sticks to acceleration mode, pull on the clutch, shift to neutral, and turn off the motorcycle. Do not turn on the motorcycle until the issue is resolved. If the throttle sticks to the closed position, turn off the motorcycle and inspect and clean the throttle and the throttle cable.

I’ve owned several older motorcycles and have run into this problem a handful of times. Through my personal experience as well as with my education in mechanics, I can give you a helpful guide as to what you should do when your motorcycle throttle sticks.

Addressing A Sticking Throttle And How To Fix It

The questions concerning a sticky throttle is probably 50/50. People are wondering what to do if they accelerate and their throttle sticks to the open position, meaning it’s stuck in acceleration mode. In this case you will struggle getting it to slow down. The other half may be wondering about a throttle that won’t accelerate at all because it’s stuck in the closed position.

It is a much more dangerous situation if your throttle cable is stuck to the open position because your motorcycle will continue to try and accelerate. It is especially dangerous if this spontaneously happens while you’re out for a ride.

If your throttle is sticking to the open position, do not attempt to turn on the motorcycle until the issue is resolved. Trying to start at such a high rev isn’t good for your motorcycle.

If your throttle sticks to the open position while you’re out on a ride, apply the brakes and steer yourself to a place where you can stop. Pull the clutch and shift into neutral then turn off your motorcycle. You will need to find an alternative way to get it home.

Once you get your motorcycle home, you will need to inspect the throttle and the throttle cable and assess for damage or sticky build-up. You’ll first need to take the whole throttle assembly off the right handle bar. See if there is any gunk built up inside of it or if any wires are crossed that would make the mechanism tight.

In either case, you should thoroughly clean out the throttle while it’s off. Be sure to also clean the part of the handlebar that the throttle connects to. Over time, a lot of deposits can build up inside and cause the throttle to stick.

If the issue is not the throttle itself, the next thing you’ll need to check is the throttle cable. If the cable sleeve is old and has cracks in the rubber, you should replace it. Dirt, metal shavings, and all sorts of garbage can get down into the cable sleeve (the black rubber that covers the cable) and binds up the cable which may be the reason you can’t move your throttle back and forth.

If the cable looks decent upon inspection, you can buy some cable lube and squirt a little bit into the cable covering at the end of the cable. You’ll then need to slide the cable back and forth so the lube can reach the whole inside of the covering.

The throttle and the throttle cable are the usual culprits to a sticking throttle cable. But if you have tried cleaning and/or replacing the throttle and cleaned the cable and it’s still sticking, you can also check where the cable connects to your carburetor.

Sometimes at that connection there are little springs and clamps that hold the end of the throttle cable that become too tight which prevents the throttle from being able to move back and forth. If needed, replace or clean these springs and clamps to ensure your throttle has the appropriate range of motion.

If your throttle is sticking to the closed position, you can still start your motorcycle but it will just idle and you won’t be able to accelerate. If the throttle becomes stuck in the closed position while you’re out on a ride, you may be able to putt your way home on back roads if you’re close enough. Otherwise you’ll need to find an alternative way to get your motorcycle home.

The fixes for a throttle sticking to the closed position will be the same as mentioned above. Inspect the throttle handle and replace/clean as needed, inspect the cable and lube/clean/replace if needed, and check the connection between the throttle cable and the carburetor. 99% of the time these will be your culprits, especially the first two.

How To Prevent Throttle Cable From Sticking

If you’ve run into the issue of a sticky throttle on your motorcycle, you know how annoying and frustrating it is. You probably don’t want to run into this scenario ever again. Luckily there are a few preventative measures you can take to keep this from happening.

Regularly applying cable lubrication to the throttle cable is one preventative measure you can take. While you’re at it, you should do this to the brake cables as well. This should be done about once a year. You may notice that when you do this, some black nastiness may come out at the end of the cable sleeve.

As disgusting as it may look, it’s also a bit satisfying knowing you were able to get all the gunk out before it caused any problems. If you routinely do this every year, you can make those cables last the whole life of the motorcycle and you’ll never need to replace them.

Another way to prevent a sticky throttle is properly covering your motorcycle when it’s not being used. Properly covering your motorcycle will prevent dirt and other unwelcomed garbage from getting inside the throttle and throttle cable and make it stick.

What To Do If Throttle Won’t Spring Back To Idle Position

Alright, so you may have found yourself fixing your throttle and feel like you may have gotten out all the dirt that was causing it to stick in the first place. Something you may run into is that though the throttle is now moving, it doesn’t do it’s natural spring back to the idle position when you let go of it.

Though you still have control over how you motorcycle reacts in a situation like this, it can still be potentially dangerous and should not be ignored. If you lose grip on the throttle, the motorcycle needs to slow down through that natural spring back (which is a safety mechanism engineers purposely made). In this case, the motorcycle wouldn’t slow down and will maintain it’s speed.

If you’ve gone through all the previous steps of cleaning everything that has to do with your throttle but you’re having issues with the throttle not springing back, your likely culprit is a loose throttle cable (a problem that won’t be fixed by cleaning it). Tightening a loose throttle cable is easily fixable. All you’ll need to do (on most motorcycles) is adjust the lock nut found just right off the throttle where the cable runs out of.

When The Throttle Spins But You’re Not Accelerating

A phenomenon that’s often associated with a sticking throttle is that after you feel like you’ve fixed it, the throttle spins but you’re no longer able to accelerate. It almost feels like the throttle is very loose.

If this is happening to you, it most likely means your throttle cable is broken or is not connected to the carburetor at all. A broken throttle cable can be difficult to diagnose because it may be snapped somewhere inside the sleeve which is hard to see.

If this is happening to you, you’ll need to replace your throttle cable. Do not attempt to fix the throttle cable as that will take more time than it’s worth and could break again in the future. Throttle cables are inexpensive anyway, so having a new one will ensure your safety.

Related Questions

Why is my motorcycle idling high? A motorcycle idles high when it is getting too much of an air and fuel mixture in a low speed or neutral position. This is usually caused by the idle screw on the carburetor being out of adjustment, an out of place throttle handle screw, a bad carburetor throttle spring, or a sticky throttle or throttle cable. Click here to see my article for more information.

Why does a motorcycle lose power when accelerating? A motorcycle can lose power when accelerating because of plugged jets in the carbs, a broken carb spring, a vacuum leak, a carb spring that’s on backwards, extra slack in the throttle cable, and poor timing advance. See my article here for more information.

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