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Pre-Ride Checklist – 11 Things To Inspect On Your Dirt Bike

A broken dirt bike sitting in my garage is not a happy sight. What’s even worse is when I haul my dirt bike out to the track or trails and it breaks down shortly after my riding session begins. There will always be those kind of days sooner or later, but I have learned how to prevent most mechanical gremlins from occurring just from experience over the years.’

I started taking maintenance seriously when I had an incident that fried a top-end when it probably could have been prevented if I had only checked the coolant level prior to riding. I have now taken the time to figure out a maintenance routine that will keep my bike running better and longer. This list of items to check are the most common things that break or cause a bike failure.

  • Oil/oil filter:

First thing to do is check the oil level and cleanliness. Running out of oil will not only end your day, but also result in a major engine failure. Some dirt bikes have a sight glass on the side of the crankcase to check the oil level, while other bikes require you to check the dipstick. Certain bikes may also require the engine to idle for a minute to circulate the oil before checking it. Always remember to check the oil level with the bike standing straight up in order to get an accurate reading. If you have a four-stroke dirt bike with an oil filter, replace it (or properly clean it if re-usable) every 1-2 oil changes.

  • Air Filter

The next common part to cause problems is the air filter. A dirty air filter can make the bike run rough due to lack of air-flow. A dirty filter will also allow dirt to get past it and into the engine. Having a clean air filter will prolong engine life. Foam only lasts so longer until it starts to degrade and literally fall apart. Strong cleaning chemicals, such as gas, will speed up this process. While filters are meant to be cleaned and reused, do not reuse one if it has any rips, damage, or if you can easily pull chunks out of it.

  • Fresh Gas

A low-performance engine, such as an air-cooled four-stroke, may not be finicky with the gas you run through it. However, old gas will eventually cause problems because it degrades with age and will gum up in the carburetor or throttle body. If you run race gas or mixed gas in a motocross bike, I suggest using it all within a week or two, if not the same day. The longer it sits out, the more it degrades. I have personally had complications using mixed race that was several weeks old; the result was me rebuilding the top-end on my 125cc 2-stroke. If your bike is not running right compared to the last time you rode, there’s a good chance that the gas is either bad, or the carburetor is dirty because it has sat for too long.

  • Spark Plug

There’s three things that an engine needs in order to run; air, fuel, and spark. Once you confirm that it’s getting air and fuel, the next thing to check is the spark plug. First of all, are you getting spark? If yes, then inspect the spark to see if it’s black and/or wet. If yes, then the plug started to or has already fouled. A proper color to see on the tip of a spark plug is tan or light brown. This means that the air-to-fuel ratio is correct. However, gas these days can be pretty lousy with all the additives and give you inaccurate readings. For more information on testing spark, read This Article on Diagnosing a No-Start.

  • Tire Pressure

Have you ever been on a ride and felt the front-end get a really mushy feeling? Sort of like a…. flat tire!? Getting a flat stinks, and it’s even less fun to change it on a dirt bike rim. Always check the air pressure of both tires before riding. The pressure will change with temperature as well, so you may need to add, or even reduce the pressure throughout the day.

Well maintained dirt bikes last a lot longer.

Well maintained dirt bikes last a lot longer.

  • Coolant

If you have an air-cooled engine, you lucked out on this one (the disadvantage is lower performance, but that may not be a necessity anyway). Before starting your bike, pop the radiator cap off and look to see if the coolant level is at or near the top. If you need to tip the bike over far to see it, you may want to figure out why the coolant is low before riding. If it was full on the previous ride and now it’s noticeably lower, it’s probably because the engine started to overheat. It could be a minor problem caused by riding too slow for too long. If you’re continuously losing coolant then you have bigger problems.

  • Chain

A properly adjusted and clean chain will ride smoother and last a lot longer. Signs that the chain needs to be replaced are: kinks, excessive wear or side-to-side play, rust, or stretched beyond the length of the adjusters. You can remove links and continue adjusting it, but there is a much higher risk of snapping a link if it is stretched that far. It’s good insurance to bring a couple spare master links with you in case you do have a mishap. You’ll need a chain-breaker as well.

  • Loose Bolts

This is often overlooked by riders due to lack of experience or just plain ignorance. Some bikes vibrate more than others, and bolts can and will come loose overtime. Loose triple clamp, subframe, or engine mount bolts may break or fall out and cause a catastrophe if you have a hard impact. It may result in broken parts, and quite possibly a bodily injury if it causes a crash. You shouldn’t need to check every single bolt for every riding occasion, but you should make a routine habit of checking all of the critical bolts and torquing them to spec every 5-10 hours of ride time. If you put a lot of hours on a dirt bike, you will start to get the feel for how long things last and when certain parts or bolts need attention.

  • Brake Pads

The faster you ride, the faster you will need to stop in order to turn or dodge an upcoming obstacle, such as a tree. A quick peak at the life of the pads can prevent an accident such as this from happening. If the pad is almost to the end of the wear bar or metal then it’s time to replace them. It’s a fairly simple job on most dirt bikes if you follow the manual. Yes, I know that if you are a guy then you probably don’t want to read instructions, but an OEM manual is a very valuable tool to have if you want to save money by wrenching on your bike(s) at home.

  • Spokes

When is the last time you have checked the tension of the spokes on your set of wheels? If you can’t remember then now is a the time to check. If any of them feel loose, tighten them until they are snug. Spoke wrenches come in many sizes for all of the different sized spokes to make the job easy. Just don’t go too far when wrenching or else the spoke will pop the tube.

  • Controls

Last, but not least, you should test and make sure all of the controls are properly functioning. Is there proper play in the clutch lever (1/8″ to 1/4″ of travel at the end of the lever)? Are the front and rear brake strong; meaning they don’t have a spongy feeling? If they feel like mush or are weak and the brake pads are good then you should bleed them to get any air out that could be in the system. This is assuming that both brakes are hydraulic. If you have drum brakes, check the tension/play in them and adjust if necessary for optimum braking performance.

Any cables that are starting to feel stiff should be lubed. Check for any fraying in the line. If any visible damage, it’s best to replace right away or else it may break when you’re 20 miles into a trail ride. As for hydraulic brake (or clutch) lines, inspect for any rips or tears in the hose. If it’s leaking at the master cylinder or caliper, there’s a good chance that the crush washer or banjo bolt has failed. Do one thing at a time when attempting to fix a part or you will get in over your head in a hurry.

While virtually any part can fail, a regular inspection and servicing of all the items on this list will give you a much better chance of riding all day without a bike problem. Preventative maintenance may not always be fun, but 30-60 minutes of scrutinizing your bike beats losing a whole or even half a day of riding. Just remember that an OEM manual is your friend. Whenever you are wrenching, always check your bike’s specific manual for proper torque and adjustment specs.

Now, GET TO IT, and ride safe!

-Tom Stark

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Honda XR200R Mods Part 2 – Weight Reduction

Honda XR’s aren’t known for being high-performance dirt bikes. That’s a given… In stock trim. If you read Part 1 on XR200 Mods, you will know that there are a lot of parts that you can replace for better performance, such as: suspension, intake, and exhaust. Part two we’ll look at the parts that can be removed or replaced for the purpose of reducing the bike’s overall weight. One of the reasons why the Honda XR200R is so popular for trail riding is its simplicity and low weight compared to other bigger four-stroke trail bikes.

Wait, hold on! Why in the world would I spend all this time, effort, and hard-earned money to put this ‘outdated’ dirt bike on a diet? That is a good question, but I will answer that with another question… Have you ridden one that is properly set-up? It won’t win you many bets in a drag race, but if the race is up and through the gnarliest of terrain, this bike will putt to the top with less effort, all the while having a grin on your face (not that riding any dirt bike shouldn’t do that anyway). It’s just a complete package of being a mid-sized bike that is easy to ride, requires little maintenance, and having engine characteristics that make it desirable while still being big enough for many larger riders with some simple mods. Not to mention the fair amount of weight that you can subtract off of the XR200 that just makes it even more fun to blaze through single track trails. As long as there’s oil in the engine and gas in the tank, there’s very little chance of these bikes breaking down. But enough praise of this simplistic and less than eye-pleasing dirt bike; let’s get to the point!

Depending on the year XR200, the curb weight (meaning wet with fluids and ready to ride) is about 230 pounds, or just under 220 without gas. Many people have tried to get that number below 200. While it is possible, it starts getting expensive the closer you get. Getting under 210 without gas is pretty easy if you have some mechanical abilities and motivation. The difference that 20 pounds makes will be like riding a new bike. If you think it’s flickable in stock form, wait till you start removing some major weight, especially the un-sprung mass! More on this later…

The XR200 engine is close to 60 pounds, which is almost one third of the total weight. There’s not much you can remove from it other than a few ounces from the flywheel while staying on a budget and keeping it reliable. Instead, we will have to look at all of the chassis and suspension components to shed the weight. In reality, you can remove weight off of or replace almost any part with something lighter, depending on how creative you can get and how much cash you want to spend. Lightweight parts comes at a price. If you want a completely aftermarket chassis and titanium nuts/bolts for your XR200, you could probably get under 190 pounds, but the cost per ounce saved will be much higher than the first 15 pounds.

Pictured Is Chuck's (with consent from TT) modified XR200

Pictured Is Chuck’s (with consent from TT) modified XR200

Sprung Weight

Sprung weight or mass is anything that is supported by the suspension. This includes the frame, engine, plastics, etc… These parts aren’t quite as critical as un-sprung parts when it comes to handling performance, but everything adds up (or subtracts if you’re taking weight off). Having a low center of gravity is also very important, and lowering the CG will make the handling characteristics feel like the bike is lighter. So, even if you can’t necessarily remove weight from a certain part, re-locating it to a lower spot (without being obtrusive, of course) on the bike can improve handling by making it “feel” like you removed weight because the bike doesn’t feel as top-heavy.

Yes, now it’s time for some numbers. Below is a list of parts that can be removed or replaced with lighter components along with their weight estimates in pounds and ounces…

  • Handlebars – Swapping to aluminum bars alone will save about 1 pound. It’s the highest part on the bike, so this is a very easy weight reduction mod. If you don’t like the stock bars anyway, this is a great time to pick out a handlebar with the right bend, sweep and width to suit you. Every rider is a little bit different, which is why there are so many bars available.
  • Snorkel cover – The top snorkel cover on the airbox is not needed unless you are riding through waterholes or in very sandy conditions. This is worth almost half a pound.
  • Muffler – The stock muffler is fairly heavy. An aftermarket silencer can save 1 to 2 pounds. Otherwise you can pull the stock baffle out of the muffler for close to the same reduction.
  • Case guards – The stock engine case guards aren’t very effective. If you don’t ride in rocky terrain, you can take them off for a 1.5 lb savings.
  • Kickstand – I don’t know of any aftermarket aluminum kickstands, but if you can weld one up, that could shave another 1 pound or so. Otherwise just take it off.
  • Steering stem – A mid 80s XR250R aluminum steering stem can be made to fit in addition to the inverted forks (see below) to replace the stock steel stem. This is worth about half of a pound.
  • Seat – Drilling out some holes in the seat base will take off some ounces. Everything adds up in the end…
  • Plastics – Trimming plastics can save a few ounces here and there. Besides, if you do it right, they can make the bike look better too.
  • Shifter – Switching to an aluminum shift lever can save several ounces. If you ride in rough terrain or tend to hit your shift lever on objects, you might want to consider sticking with a stock steel lever. This won’t make much difference as far as handling goes because it’s relatively low on the bike anyway.
  • Pegs – The stock steel pegs are heavy compared to aluminum ones. If you can find some cheap aluminum pegs off a Honda MX bike and adapt them, that can drop another pound or so.
  • Tabs – If you really want to get crazy, grinding off any unneeded tabs from the frame will save a few ounces here and there. Just remember that it will start to rust if you leave the metal bare. This is a good excuse to strip the whole frame down and get it re-painted or powder-coated to make it look like new.

Total Sprung Weight: 6 pounds

Un-sprung Weight

Removing any kind of weight is good, but if you can shed un-sprung weight, the results will yield significant results as far as handling and performance goes. Un-sprung mass is all of the suspension components, such as the forks, wheel assemblies, shock, swing-arm, linkage, etc. Removing weight from these parts is more effective than if you were to remove the same amount of weight from sprung mass because it is the rotating and moving with the ground surface and suspension.

Lightweight aluminum rims are highly sought after compared to steel rims because they can reduce a great percentage of rotating mass. A lighter wheel will be a light more responsive when going over obstacles and bumpy terrain because it doesn’t take as much force to move it. This allows for greater traction and improved handling. I don’t want to go too in-depth on this subject or else you’ll be sitting here all day. There’s no set equation that determines how much un-sprung weight removed that would equal the amount sprung weight. Just know that un-sprung mass has a greater effect on handling performance.

Now we’ll look at the key parts for removing weight from the suspension and wheels to make the XR200 the bike that Honda should have made…

  • Swing-arm – The stock swing-arm on XR200R’s are steel and can be swapped out for a XR250R aluminum swing-arm (’86-’89) with little modification. It’s about 3.3 lbs lighter and can be found on eBay for under $100. Look for one that still has everything on it if possible, such as the chain guide, slider, and axle adjusters.
  • Linkage – Another fairly easy weight savings is switching to an aluminum swing-arm linkage (1984-’85 XR250R). It’s just over 2 lbs lighter, but is debatable on being sprung or un-sprung mass. For less than 50 bucks, this is another good mod. However, the grease fittings may be broken off, and new bushings may be required.
  • Forks – The biggest fork mod for weight savings is switching to a CRF150R or CR85R front end (depending on what size front wheel you use). It’s about 6 lbs lighter, but is a little more work and costs several hundred depending on how hard you look. This is by far the most expensive mod on this list, but yields good results on both the weight and performance side of things. A servicing and re-valving will make this bike handle any trail you throw at it, especially if the rear suspension is dialed in as well.
  • Wheels – A late 80s RM125 rear wheel is a good 4.5 lbs lighter than the stock XR200 wheel. It can be modified with new spacers and some bearings that match the XR axle size. A complete wheel can be had for 100 bucks or less on eBay. Late 80s RM125 rear wheels are 18″, which is easier to find tires for. Many people swap over to 18″ XR250 rear wheels for the better traction you get from a bigger diameter tire. However, this will have some effect on gearing.
  • Sprocket – The rear sprocket is one of the easiest weight saving mods. The stock steel sprocket is about 1.7 lbs heavier than an aluminum sprocket. You can buy an aftermarket rear sprocket or certain bikes that have the same bolt pattern will work. Some examples are: mid to late 1980’s XR250, ’99 and newer YZ125, ’01+ WR/YZ250F, or ’01+ WR/YZ400/426/450F.
  • Tires – This depends on what size wheel you have and what kind of tire you want. The size that a tire shows may not be exact. Trials tires give good traction, but weigh more than standard off-road tires. If you want the lightest tire, go with something that’s narrow.

Total Un-Sprung Weight – 18 pounds

If you put all of these savings together (assuming you haven’t added any weight), you should meet the goal of having a sub-200 pound XR200R trail bike without gas! I could go on about every little part that you can replace or make a custom lightweight replacement for, but that’s when a simple and budget-minded project turns into a full-fledged hobby and pocket burner. Other than the CR/CRF front-end on the lists above, all of these parts or mods are relatively cheap and easy for a DIY person to do.

I can’t take all of the credit, as some of this information was from founded from members on ThumperTalk. If you have personally done additional modifications to make your XR200 lighter, please feel free to post your results or email me so I can add it to this article. This information, like all of the articles on Motocross Hideout, are for the benefit of other riders that want to learn more about their dirt bike and be able to work on it themselves.

-Tom Stark

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How To Swap TTR125 Carb to VM24 – Video Tip

Having starting or running problems with your TTR125? There’s a good chance that the stock carburetor is your problem. Instead of spending hours trying to fiddle with it, a carb swap can save you a lot of headaches and make your bike start easier and run much cleaner. Here’s a step-by-step video tutorial on how to convert to the Mikuni VM24 carburetor. If you’re unsure about this conversion or have questions on why you should do it, read all the details on swapping out the stock carb HERE.

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