Dirt Bike Cleaning – A Beginner’s Guide

In an ideal world, you go out riding at the weekend, get seriously dirty, come back and wash the bike. But it’s rarely an ideal world and often you return far too late to bother cleaning your scoot. It’s work on Monday so by the time you break out the jet washer three days later, you bike is encased in rock hard mud that really wants to stay put.

So for our blog today we’re looking at how to clean your dike bike properly and get it back into looking something like the manufacturers intended, rather than some kind of pre-historic swamp monster. Hopefully there are some pointers for the newbies out there and maybe a few cleaning tips for the more experienced riders.

Mud-covered orange KTM dirt bike on a paddock stand against a brick wall before washing
CAKED IN WELSH MUD
Close-up of a mud-caked engine and frame on a dirt bike
THE ENGINE IS COVERED
Mud-caked front tyre and wheel of a dirt bike
UNDER THE SEAT THERE"S MORE

So first off we need a dirty bike that’s been left in the garage – step in Julian’s 2013 KTM EXC250, just off the Welsh 2 Day Enduro. With 320 miles of Welsh mud still there, it’s an ideal starting point.  Put it on a stand that will enable you to raise each wheel of the ground. We use an ASV Kickstand as it leaves the bash plate clear and is easy to change from back to front wheel off the ground.

CLEANING STAGE ONE: PREPARATION AND PREWASH

Mud-streaked exhaust outlet on a dirt bike with the pipe left uncovered
THE EXHAUST NEEDS COVERING
Wiped metal exhaust outlet on a muddy dirt bike
WIPE OFF THE OIL
Exhaust outlet covered with a black taped bag on a muddy dirt bike
GAFFER IT UP

That mud is hard, so breaking out the jet wash straight away is a silly move. You need to get it soft again, but before that, you need to stop water getting into the pipe, so clean off the end can and if you don’t have a butt-plug handy, seal it up with some gaffer. The air filter and number board will still protect the inlet at this point so no worries there, we’ll cover it later.

Hose with a fine spray nozzle washing the front mudguard and number plate of a dirt bike
USE A HOSE ON FINE SPRAY
Hose with a spray nozzle wetting the mud on the lower frame of a dirt bike
WET ALL THE MUD
Hose spraying water at the muddy front forks and engine of a dirt bike on a stand
GET EVERY ANGLE

OK now with just the hose, soak all of the mud of the bike. Get it really drenched and then go get a cup of tea, read a magazine, surf the net for a good ten minutes so the water soaks in. You could even plan your next next motorcycle adventure …

CLEANING STAGE 2: FIRST WASH

So now it’s time to break out the jet washer. You don’t need anything super powerful; in fact the more powerful models will strip the grease from all your bearings really quickly. We use a £40 own-brand model from one of the big DIY outlets – the last one lasted fifteen years of regular use, so we got our money’s worth. It’s pointless using any dirt bike cleaner at this point because you will just be spraying it onto thick mud, so hold off with the pink stuff.

Green electric pressure washer with its hose and trigger lance coiled on wet ground
B & Q OWN BRAND JET WASHER

Start under the mudguards, as that’s where most of the mucky stuff will be, then move onto the mountain of clag that’s on the exhaust. This tends to be worse on a two-stroke as there is more pipe for it to catch on.

Taking one side of the bike at a time, work your way from one end of the bike to the other, shifting the mud with a wide spray rather than a laser like jet to avoid too much water ingress to places it shouldn’t be. Perfect.

Pressure washer jet blasting mud from under the rear mudguard of a dirt bike
START UNDER THE MUDGUARDS
Pressure washer jet cleaning mud from the front forks and exhaust of a dirt bike
BLAST OUT THE MUD
Pressure washer jet cleaning the swinging arm and rear wheel of a dirt bike
SHIFT THE LOWER MUD LAST

When most of this is done, you need to do the underside before finishing so get a second box style bike stand, make sure the fuel is off and lay your dirt bike down with the bars turned to full lock and grip resting on the box. You’ll see no end of additional mud on the bottom of the swingarm, bashplate, linkage – if you have one – and up underneath the mudguards, but don’t go mad on the linkage – maybe use a soft sponge to clean it to protect the bearings. Flip the bike to the other side and repeat.

Dirt bike held on a red paddock stand against a brick wall, seen from the front
LAY THE BIKE DOWN
Dirt bike laid on its side on wet ground so the underside can be cleaned
ENSURE THE PETROL IS OFF
Underside of a dirt bike with the bash plate and engine exposed and muddy
CLEAR THE UNDERSIDE

OK so now take a breather. There’s now about ten kilos of dirt on the floor and continuing with it there will just put it back on the bike. Move the motorcycle out of the way, sweep up the worst of the mud, shovel it into a bucket and chuck it in the green bin, that way we start stage three with a relatively clear deck.

Orange bucket, shovel and brush on a muddy driveway
YOU NEED TO SHIFT THE MUD
Orange bucket of thick brown mud with a shovel and brush beside it
SHOVEL IT INTO A BUCKET

Now we are now going deep into the bike cleaning, so we need to remove the airbox cover, pull out the air filter and replace it with a cover to seal up the air inlet. Don’t improvise – go to your local dealers and buy the proper part for the job!

CLEANING STAGE 3: FINAL WASH

Hand pulling a cover off the side of an orange dirt bike
PULL OFF THE COVER
Airbox cover removed from a dirt bike to show the foam air filter
REMOVE THE FILTER
Airbox of a dirt bike with the filter removed and an orange blanking plate fitted
FIT THE BLANKING PLATE

It’s time to break out the dirt bike cleaner as the worst of the clag is gone. We use Muc Off as it’s alloy friendly,  does the job and we always get a good deal at the annual dirt bike show!  Spray all parts of the bike, again keeping it on a wide spray rather than a jet to cover everything. As the inlet is blocked you can go right into the air box

Pink bike cleaner in a spray bottle and a five-litre container beside it on a stand
WE USE MUC-OFF
Hand spraying pink bike cleaner onto the side of a dirt bike
SPRAY LIBERALLY
Hand spraying cleaner into the airbox area of a dirt bike
EVEN IN THE AIRBOX
Hand spraying pink bike cleaner onto the side of a dirt bike
AND AROUND THE SHOCK

We find that the general bike cleaners are not as good at removing old oil and dry lube from the chain and sprockets, so after moving the front sprocket guard out of the way, spray the chain liberally with chain cleaner such as WD 40’s branded product. Leave both this and the Muc Off to work for five to ten minutes.

Muddy chain and front sprocket area of a dirt bike before cleaning
MOVE THE CHAIN GUARD UP
Hand spraying WD-40 onto the chain and rear sprocket of a dirt bike
USE CHAIN CLEANER IF AVAILABLE

While you are waiting, go and get a bucket of warm water with either washing up liquid, or ideally some car shampoo to do all the bike plastics, tank and seat. These respond better to a sponge than just a blast with the jet wash, so get busy with the suds before returning to the jet wash. You might need to use wire wool on the header or expansion pipe to remove the staining that may have occurred.

Hand polishing the orange and white plastics of a dirt bike with a sponge
SOAP ME UP - GET THE SUDS TO WORK ON THE SEAT AND PLASTICS

Now go grab the wand and get busy with the pressure washer, trying to start on the higher bits of the bike and working down. It will take multiple passes as you will constantly miss bits and need to return to them.

Pressure washer rinsing the engine area of a dirt bike on a stand
CLEAN OUT BY THE FRONT SPROCKET
Pressure washer rinsing the front wheel and forks of a dirt bike
ENSURE THE BRAKES ARE CLEAN
Pressure washer rinsing the rear wheel and swinging arm of a dirt bike
BACK AND FRONT

Last stretch now, so put the bike back on the stand and finish the jet washing, ensuring you have given the chain a good cleaning but again not going too mad on this as the chain cleaning spray should have done the trick.

Clean KTM dirt bike on a paddock stand against a brick wall after washing
FIE UP THE MOTOR AND RUN TO DRY EVERYTHING OUT

Once you have finished with the water, leave your dirt bike for ten minutes to drip dry, then use a clean rag to fully dry the air box. Refit a freshly cleaned air filter and replace the air box cover.

Wipe the chain to dry as much as possible and lubricate it straight away or it will rust.

The final step now is to run the bike so on a two-stroke, we tend to leave the petrol off, start it up and let it run until the fuel in the carb runs out to full dry the engine and exhaust.

You can break out the silicone or “Bullsh*t Spray’ at this point to make all your plastics shiny and black again, or even use a product like Muk Junkie’s excellent Lazy Boy shine to give your scoot a showroom look. Nice.

There you are done – ready for the next ride!

Clean KTM dirt bike with orange and white graphics standing on a paddock stand beside a hedge and brick wall

SO DID WE MISS ANYTHING? DO YOU CLEAN YOUR DIRT BIKE DIFFERENTLY?

We hope this guide to dirt bike cleaning has been useful for beginners and experienced riders alike. If there’s anything we’ve missed that you do when washing your own dirt bike, please let us know in the comments below. Obviously you need to follow the manufacturers instructions for all products mentioned and read the manual for your bike to ensure there are no specific requirements for your machine.

if you fancy getting our bikes dirty rather than yours  and want to find out about the motorcycle expeditions we offer around the world, visit our Ride Calendar to see what’s on and when. Don’t just dream it – ride it…

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