Unless you are really wealthy, you will need to learn how to do dirt bike maintenance. Learning these basic skills will allow you to save tons of money in shop labor hours, and help prevent costly shop visits down the road.
More than most machines, a dirt bike requires a lot of maintenance. Just think about it, you have a engine that is running at high RPMs, in an unfriendly environment. It is not like you are driving your car down the interstate. You are driving through dust, dirt, and mud.
Here are 5 dirt bike maintenance items that you should never neglect!
Air Filter Maintenance
The air filter on your dirt bike should be changed every ride. You ride in dusty conditions that are harsher than what most engines will ever see. In order for your engine to last a long time, you have got to ensure that none of that dirt is making it into your engine.
So, you might be thinking to yourself, how in the world am I supposed to afford to ride if I have to buy a 30 dollar air filter every single time I go out. The answer is you don’t. Foam air filters, like you will find on most dirt bikes are able to be cleaned, reoiled and reused.
Some companies offer cleaning systems that makes this very convenient where you always have a nice clean filter ready to use. They are not too costly (not really cheap either), but you can get by just fine without one if you can remember to clean your air filter, re oil it, and store it in a gallon ZipLock bag.
How many Air Filters do I need?
I currently have 3 air filters for my dirt bike. One is on the dirt bike, one is oiled and ready for use, and the other one is somewhere in between. If I am lucky ready for use… My process is to take my bike out of my trucks, wash it, then put it on the stand. I will then put a new air filter on by taking the one that is oiled and in the ZipLock bag, coat the rim that touches the air box with grease (to help it seal better) and swap the air filters out.
Then, when I have time to get to it, I will clean the dirty air filter, oil it, an put it in a ZipLock, ready to go for next time.
If you can make this part of your standard practice of putting your dirt bike away, you will do yourself a huge favor.
Something that you need to do after every ride, and especially after every time that you clean your bike is to lubricate the drive line parts. This involves putting chain lube on your chain and squirting some grease on your axles.
To lube your chain, put your bike on the bike stand where the rear wheel can rotate freely. Put the bike in neutral and then spray the chain lube on the chain as you turn the wheel. This will move the chain and make sure you are covering the entire chain. One coat on the chain is all you should need.
To grease your axles, you can either pull the axle tubes and coat them with grease, or jam some in-between the wheel spacer and the swing arm. It will eventually work its way down where it needs to go. I do this every time I put the bike up, and fully lube the axles once or twice a year.
Change the Oil!
This frequency of when you need to change the oil depends on the type of dirt bike that you have. If you have a 2 stroke dirt bike, the gear oil should be changed every 10 or 20 hours. Most of the time this is going to equate to changing it every other ride or every third ride, depending on how long your rides are.
With a 4 stroke, this is what I do. I drain and replace the engine oil every ride. I change the oil and the oil filter every other ride. This is probably excessive, but changing the oil is pretty cheap insurance against harmful damage to your engine.
I picked this practice up from a buddy of mine who races street bikes at the expert level. He changes his oil after every weekend at the track. He uses some crazy expensive oil that is 30 bucks a quart. I don’t go to this extreme and will just change it with the standard motorcycle oil after every time at the track.
An engine rebuild is going to take at least a day and will cost upwards of 1000 dollars if you have it done at the shop. Changing the oil is cheap and takes only a couple of minutes.
I do a radiator flush once per season. I typically will do this at the end of the season so I don’t forget when the season starts back up. If you live in a harsh climate where you drain the radiator fluid out at the end of each season, then simply do the flush at the beginning of next season.
To perform a radiator flush, I first drain all of the radiator fluid out of the cooling system. Next, I will leave the drain plug open and pour an entire gallon of distilled water (you can get distilled water at your local grocery story for around a dollar) and just let it drain out. This is to flush any remaining fluid and minerals out of the radiator.
Once this is done I will replace the drain plug and fill the radiator back up with radiator fluid. I use Engine Ice. Engine Ice is formulated to not cause mineral build up, so that’s why I use it. If you can’t find Engine Ice, or prefer a different radiator fluid, use what you have. Just remember to fill it back up!
Fork Oil Change
If you are running a dirt bike with oil forks, when was the last time you change the oil in them? This is probably the biggest pain of the 5 things that we are talking about. As a result it is the most commonly “overlooked” maintenance item on a dirt bike. I have seen dirt bikes that have never had their fork oil changed. Don’t do this. Just change it once a year. After you have done it a time or two it should only take you 20 minutes or so.
Changing the oil is going to vary from manufacturer to manufacturer, so I would recommend that you go on YouTube to find a video that shows how to do it. Often times, you are just going to be able to find a video that shows how to rebuild the fork. That is fine, because part of rebuilding the fork is draining and refilling the oil. Just figure out how to drain the oil, and then how to refill it. If you watch a video a time or two you should have a good idea about how this process is done.
The oil that you use in forks is a particular kind of oil. It is called, obviously, fork oil. Look at your service manual to figure out the type of oil that you need. I run KYB forks with an inverted cartridge. It takes me about 1 pint of 5T fork oil per fork if I am doing an oil change. Go ahead and buy 3 pints so you will have some left over in case this estimate is off.
Addressing these 5 dirt bike maintenance items in a timely manner will help ensure that your dirt bike has a long life. Wrenching on dirt bikes is fun, but riding them is more fun, so the more time you can spend riding the better. The real pain job of the 5 mentioned is the fork oil, but lucky for you it only has to be done once a year.
If you can get in the habit of addressing the air, oil, and lubrication after every ride, you will be in great shape. Stay safe out there!