You know that sinking feeling you get when you first lay eyes on a motorcycle repair bill? Yeah, us too.
Unfortunately, a lot of service and repairs for bikes can be expensive. One such repair that often sends bikers running for the hills is valve adjustment.
But what exactly is valve adjustment, why does it need to be done and how much does motorcycle valve adjustment cost? We’re here to break it all down for you. So saddle up, pardner – we’re about to hit the open road!
What Is a Valve Adjustment & Why It’s Important?
A motorcycle’s engine has valves that open and close to allow air and fuel mixture into the combustion chamber and exhaust gases out.
Over time, however, the gap between the rocker arms or cams and the valve stems (also referred to as valve lash) increases or decreases due to wear depending on valvetrain design. This is really bad for your engine for a number of different reasons.
Valves that have excessive clearance will make a loud and annoying ticking sound. If the wear is bad enough, then it will also reduce the performance of your engine, especially at higher revs. Clattering and ticking valves will cause more and more damage to the valvetrain over time as they wear.
On the other hand, valves that have insufficient clearance will not cause any sound, but will make up for it in serious engine damage. Tighter valves will cause hard starting and rough idling, and if they get even tighter over time – they will melt.
As you can see, adjusting the valves on your motorcycle is extremely important to the health and longevity of your engine.
Motorcycle Valve Adjustment Cost
OK, we talked about what valve adjustment is and why it’s so important, but how much does it usually cost?
Well, it largely depends on the complexity of the valvetrain on your motorcycle and the number of valves, in addition to how easy they are to access.
On average, most motorcycle valve adjustments will cost between $300 and $600. You really don’t need too many parts for a valve adjustment on a motorcycle – just a few gaskets and that’s about it.
However, in order to get access to the valves, you need to remove the gas tank, fairings, etc, which takes up a lot of time. On older and more simple motorcycles, a valve adjustment can be done in under 2 hours and would therefore cost around $250 for parts and labor, but it may take 5 or 6 hours on more modern motorcycles. At around $100 for 1 hour of labor, that totals to at least $500 – not fun.
How To Save Money on Motorcycle Valve Adjustment
If you’re looking to save hundreds of dollars and basically make the valve adjustment completely free, then you could try adjusting the valves yourself. However, this is not for the faint of heart and we only recommend attempting it if you have a good understanding of motorcycle engines.
There are hundreds of how-to videos detailing the whole process of adjusting the valves on a motorcycle engine and you can also quite easily get your hands on a service manual for your specific motorcycle.
Now, by following the service manual for your motorcycle, you can quite easily check and adjust the valves on your own. However, valve adjustment requires actually feeling whether the valves are tight or not with a feeler gauge. As you can tell, this is the most difficult part of the valve adjustment process, but once you get the hang of it, it can be done quite easily.
All you need to do is feel whether the feeler gauge fits snug and not too loose or too tight. It’s difficult to describe and it’s also something that you will just have to learn on your own.
With that said, if you’re not confident in your ability to adjust the valves, then we recommend taking it to a professional motorcycle mechanic. If you mess this up, by overtightening the valves or mistakenly leaving a foreign object under the valve cover, then you can seriously damage your engine.
How Often Do Valves Need to Be Adjusted on a Motorcycle?
Luckily, you don’t need to adjust your valves that frequently. In fact, most motorcycle manufacturers will recommend a valve adjustment interval of between 6,000 and 15,000 miles. However, this largely depends on the motorcycle and how you ride it.
For example, if you do a lot of short trips around town, then your motorcycle’s engine will never really get up to temperature and the oil will not be able to properly lubricate all of the parts, leading to more wear and tear.
On the other hand, if you frequently ride long distances at high speeds, then your motorcycle’s engine will get much hotter and the oil will be able to properly lubricate all of the parts, leading to less wear and tear.
How Do You Tell if Your Valves Need Adjusting?
If you’re not sure when the last time your motorcycle’s valves were adjusted, then there are a few ways to tell if they need to be adjusted.
First, you can simply check the maintenance schedule in your motorcycle’s owner’s manual. If it’s been more than 6,000 miles since the last adjustment, then it’s probably time for another one.
Second, you can listen for a quite loud ticking noise coming from the motorcycle’s engine. If you hear a loud ticking noise, then it’s definitely time for a valve adjustment.
Third, you can check the motorcycle’s performance. If you notice that your motorcycle is not performing as well as it used to, then it might be time for a valve adjustment.
Why Don’t Motorcycles Use Hydraulic Lifters?
One interesting question that we get asked quite often is why motorcycle engines don’t use hydraulic lifters like car engines do.
The simple answer is that motorcycle engines rev much higher than car engines and hydraulic lifters simply can’t keep up with the high revs.
There are some exceptions, however. The Honda CB700SC had hydraulic lifters and it easily revved up to 10,000 RPM, but when you go above 10,000 RPM the imperfections of the hydraulic lifters become too big.
Hydraulic lifters can vary the valve lift quite significantly at high RPM due to oil pressure fluctuation and valve spring stiffness. Imprecise valve lift at high RPM will cause surging and other problems.
So, in order to rev up over 10,000 RPM, motorcycle engines need high-precision solid lifters at very high RPMs.
What Causes Valves to Go Out of Adjustment?
Valves can go out of adjustment for a number of reasons.
The most common reason is simply because the motorcycle’s engine is getting old and the parts are wearing out. As the parts wear out, the valve lash increases or decreases depending on the valvetrain design.
Another common reason is because the motorcycle’s engine has been improperly serviced. For example, if the motorcycle’s oil is not changed frequently enough, then the oil will break down and will not be able to properly lubricate all of the parts. This will lead to increased wear and tear on the parts and can cause the valves to go out of adjustment.
Motorcycle valve adjustments aren’t exactly the cheapest service, with prices ranging from $250 to $500. However, if you’re motorcycle isn’t performing as well as it used to or if you hear a loud ticking noise, then it’s probably time for a valve adjustment.
Just be sure to take your motorcycle to a qualified motorcycle mechanic who has the experience and the tools to properly adjust your valves.
Jake is the site’s primary contributor.
Motorcycles and automotive repair have been a big part of his family for generations, therefore it’s only natural that he decided to become a heavy-duty diesel tech.
Outside of work, you’ll find Jake restoring and riding rare street bikes and ATVs.