Gear change problems can lead to several problems, including clashing and grinding whenever you shift.
The problem can make for a poor riding experience, which is why you need to rectify it as soon as possible.
In this article, we discuss motorcycle gear change problems and their solutions.
What Causes Gear Change Problems on Motorcycles?
Damaged gearbox, maladjusted shift pedal linkage, poorly timed clutch input, and a faulty clutch cable are a few of the common causes of gear change problems on a motorcycle. If you find it difficult to change gears, these are the first things to check.
Poorly Timed Clutch Input
In most situations, it’s best to start with personal accountability; if the rider doesn’t release the clutch lever slow enough, the spines on your gearbox can’t engage. By doing this, you can create a smooth shift. This ensures that there is no risk of locking your back wheel.
You can also avoid any noticeable drag. To make this easier, you can blip the throttle. You get a much smoother shift through this since it helps the engine revs match the road speed.
Maladjusted Shift Pedal Linkage
It’s best to start with components outside your engine, something like a shifter adjustment causing trouble somewhere in the linkage.
Adjusting the shift pedal’s height to suit the rider’s preference or foot size can cause a bind in your bike’s shift linkage.
A bind in the linkage prevents the shift claw from pushing all the way in, making engaging the gear impossible. If you’re having gear change problems and you or someone else has recently adjusted your shifter’s height, this is a healthy place to start your troubleshooting.
Faulty Clutch Cable
The next component I’d inspect is your clutch cable.
Both clutch cables wear and tear and poorly adjusted cable tension can cause an improperly functioning cable system.
If you’re lucky and your cable’s still good, you can probably hit it with a quick re-readjustment and keep ripping. If your clutch line is too slack, you’ll experience lagging upshifts while clunky and tense downshifts indicate too much tension, meaning you’ve got to slack that clutch cable a bit.
If you’ve made it this far, then not only are you shifting correctly, but there’s also no bind in your clutch linkage, and your clutch cable is in healthy condition and properly adjusted. Next step?
Sorry, sibling, but you might have worn out clutch. A worn-out clutch causes a gear shifting during shifts.
Generally, both gearbox wear-and-tear and clutch abuse via poor shifting means that the only fix is replacing or rebuilding your gearbox.
Why Are My Gears Hard to Shift on My Motorcycle?
An impaired clutch system is the leading cause of hard shifts on a motorcycle.
If you’re experiencing hard shifts without power loss to wheels, it could be the result of one of the following mechanical malfunctions:
- If you subject your bike’s shifting fork or slider drum to wear-and-tear, you’ll experience missed shifts, or at the very least, hard shifts.
- An elongated clutch wire prevents disengagement, which causes hard shifts.
- If your clutch lever is hydraulic, oil pressure, low oil or cable bulging could be the culprit.
Experiencing challenging shifts with visible power loss can indicate significant transmission damage, something to the tune of bent rods, gear tooth breakage, bent rods, or damaged synchro/worn-out clutch plates.
If you haven’t caused some critical damage, the likely culprit is an issue with your clutch, like a poorly adjusted linkage or a cylinder leak on a hydraulic clutch.
Check your manual for service and adjustment specs and to ensure that you’re using the proper fluids.
Unless you’re on a vintage bike or a custom chopper, you probably have a wet clutch that must be bathed in engine oil to function correctly.
The wrong oil type will prevent the clutch from engaging, and you’ll experience rough shifting for sure, causing damage to your clutch and gearbox in the process.
How Do I Know If My Gearbox Is Damaged?
Chunky, hard shifting, a burning smell, a whirring, chattering, and shaking from your transmission are a few signs your gearbox is damaged.
Noises could mean insufficient lubrication or damaged components.
If a burning smell wafts from the gearbox to accompany the noises, or on its own, you might have some burning oil or overheat from friction.
A transmission job is big, so it’s probably a good call to seek one out if you’re not a professional mechanic.
Even if your motorcycle’s clutch doesn’t feel right, get it checked now. A gearbox problem seldom fixes itself, and the laws of physics tell us that the degradation of your gear system will only worsen.
Please also read our article about 7 symptoms your motorcycle chain is too loose.
What Are Early Signs of Transmission Failure?
High engine revs, missing or slipped gear shifts, or a stuck clutch lever are signs of motorcycle transmission failure.
If you release your clutch lever and your motorcycle’s RPMs shoot up, and you hear high revs, the clutch isn’t engaging.
Not all the engine’s power is transferred to the transmission to interlock, shooting your RPMS up without accelerating your motorcycle.
Missed or Difficult Gear Shifts
Clunking sounds and jerkiness while shifting indicate clutch trouble.
The jerking and unpleasant sounds result from separation among the steel plates, obstructing the bike from changing gears.
When you yank in that clutch lever, the plates are supposed to leave a precise distance between one another. If there isn’t enough clearance between the friction and steel plates, you’ll feel that clunky action.
If you’re lucky, it’s just a clutch cable adjustment causing these shifts. If your luck’s no good, though, you might have worn clutch springs.
Jammed Clutch Lever
This seems obvious, but if your clutch lever is stuck, whether stuck pulled in or popped out, there’s a problem.
Dirt and debris in the clutch assembly can force the steel plates and friction plates to stick to one another. Sticking plates could also be the handiwork of a broken clutch spring.
Regardless, sticking plates incur damage over time, and your clutch might be jammed up indefinitely.
Stuck in Neutral
If you try to shift your bike from neutral into first gear and the shifter moves, but the bike stays neutral, you have a damaged clutch.
If it’s this bad, the chances are that your clutch assembly is stuck due to seizing.
The clutch transfers power via friction. If your clutch isn’t lubed up with the appropriate amount of oil or you’re running contaminated oil through your gearbox, this friction can cause overheating.
Enough overheating can seize your clutch.
Make sure to also read our article about whether motorcycle engine braking is good or bad.
What Are the Signs of Low Gearbox Oil?
The two most obvious signs of low gearbox oil are hard shifting, a burning smell, grinding or clunking noises, transmission leaks.
Like we discussed above, oil prevents your gearbox from overheating.
If your gearbox overheats, the friction intensifies, and friction plus time equals corrosion. Once corrosion passes a certain point, the damage done to the components can render your gearbox useless.
Clunky and Grinding Sounds Coming from Gearbox
This one’s tricky. Grinding noises indicate a problem with your gearbox that could be low oil but could be a few other things as well. If you’re unsure how to diagnose the sounds, take your motorcycle to a trusted mechanic to validate that low oil is the only problem.
That said, a properly functioning gearbox won’t make abrasive grinding noises, and your shifting should be smooth and consistent.
If your gearbox responds to your shift input with a loud clunking or grinding sound, this could indicate that your gearbox is low on oil.
Missed Shifts and Slipping Gears
Gear slippage is another token of low gearbox oil.
If your gearbox oil level is below the suggested capacity, your gears will miss their shifts. It won’t happen all the time, and it’s an easy problem to ignore… at first.
Eventually, though, low oil causes severe damage that may require a gearbox rebuild to rectify. Save yourself some money and get your motorcycle looked at at the first sign of missed and slipping gearshifts to ensure you don’t damage your gearbox beyond repair.
Also read our article about things to check when motorcycle has cold start problems.
How Much Does it Cost to Fix a Gearbox?
A gearbox rebuild can cost between $100 and $1300, depending on the problem and the make and model of the motorcycle.
Now, if your problem only requires a simple clutch adjustment, you’re looking at nominal parts and labor cost. But if your bike’s sitting in for a complete rebuild, you’ll probably hit a grand.
The parts alone probably put you between $400 and $500, but it’s a big job. The labor will probably run you between $500-$750.
Many owners of older bikes opt-out of a transmission rebuild in favor of a motor swap. They’ll find a used version of their bike with a healthy engine and drop that sucker onto their faithful moto-mule.
How Long Should a Gearbox Last?
The clutch of a well-kept motorcycle lasts between 20,000 and 60,000 miles. However, as with any mechanical component’s longevity, this lifespan depends on the manufacturer and the owner’s attention to maintenance.
If you push your clutch to its limit, power shifting and running through your friction zone over and over again with constant gear changes, you could burn the thing out in 5,000 miles.
A responsible rider who services, maintains, and stores their bike properly could easily pass 100,000 miles without a clutch problem.
Does Changing Gearbox Oil Make a Difference?
Most motorcycles use the same oil throughout their gearboxes and motor, and changing your oil is an essential part of lubricating not only your gearbox but your whole engine.
Oil reduces the heat caused by the steady friction taking place in your gearbox. A lack of lubrication or lubricating your clutch assembly with dirty oil is an easy way to cause wear and tear in your gearbox.
The last thing you want to experience on your motorcycle is engine lock-up.
Engine lock-up is when your pistons overheat and seize due to a lack of lubrication.
The metal expands when it gets hot, and if it gets hot enough, the metal will fuse into itself as it cools. In some cases, it stays locked like this forever.
The same oil lubricates your clutch. Lack of lubrication in your gearbox can cause your clutch bell and flywheel to overheat, and your bell can fuse onto your flywheel when hot, then cool into one another to fasten together.
If the fly can’t spin, you aren’t going anywhere. Since you ‘re using the same oil in your bike’s transmission and motor, you must keep the oil clean and complete.
It’s essential not to wait until you’re experiencing issues this severe before you inspect, adjust, and change your oil regularly.
If you wait until your gearbox is problematic to do so, it may be too late.
If you’re not mechanically inclined, no biggie. Your local motorcycle mechanic can knock out an oil change for you in less than an hour for a relatively low price.
If it’s been a while, have him inspect the gearbox to ensure you’re starting your routine before you’ve caused significant damage.
Believe it or not, changing your oil also boosts your fuel economy.
If your oil level is below the suggested amount, or if your oil is dirty and contaminated, your engine’s components are experiencing resistance that the manufacturer didn’t factor into its intended mechanical process.
As a result, your machine, to push against the opposing force, has to burn more fuel to pull off the extra duty.
The oil keeps motor parts lubed, cooled, and sliding efficiently, keeping your engine working as intended and your gas expenses down.
What Noise Does a Bad Gearbox Make?
Like many manual transmissions, a damaged motorcycle gearbox emits rigid mechanical sounds like grinding and clunking.
That said, be sure that the sound is coming from the gearbox.
The engine, exhaust system, wheel bearings, and driveshaft can all make similar noises during different stages of failure.
A grinding sound can be characteristic of a lack of lubrication in many areas.
If you experience these noises and you can’t diagnose where they’re coming from, check in with a mechanic and be sure your gearbox has plenty of lubrication, as well as the rest of your motorcycle.