Let’s face it, if you ride a motorcycle, sooner or later you are going to find yourself stranded on the side of the road. Perhaps the only thing worse is watching your bike ride off on the back of a tow truck. So before you whip out your cell phone and make that expensive call for a wrecker, it’s worthwhile to take a few minutes to make sure there is not an easy fix that will have you back on the road for free. This easy five item checklist will at least allow you to make a more informed decision before you have to make that dreaded call and if you’ve found yourself broken down without a phone, it may save you from a long walk.
Use Your Senses
One of the best diagnostic tools in your arsenal is your five senses, and the good thing is they don’t take up any room in your tool roll. Before you even consider unpacking a single tool, take some time to give your bike a good “sensory diagnostic.”
I usually start by thinking back to what happened just before I found myself sitting on the side of the road. Did the bike feel or sound different? Often major engine failures are announced by unusual vibrations or sounds and if your bike is making some horrible noises, then it’s time to go for the phone. If not, take some time to carefully look over the entire motorcycle, paying careful attention for loose fasteners, leaking fluids or even missing parts.
Also note if anything smells bad. Plastic, oil, transmission fluid, and clutches all smell pretty bad when they burn, which can also help narrow down the problem. For the really hardcore rider, you can also take a taste of your oil to make sure it is not fouled with gas, water, or coolant. Not something I would personally recommend, but some old timers swear by it…
If your bike checked out ok with the sensory diagnostic, then the next thing to check is your battery. As motorcycles get more and more electronics, a properly maintained battery is essential for proper operation.
The easiest way to check your battery is to turn on the key and hit the starter button. If the starter spins over, then the battery is probably ok. If you just get a clicking noise or nothing at all, then it’s time to start checking battery connections.
On some bikes, the battery is just not accessible and you may have to give in at this point, but if you can get to your battery, make sure that the connections are clean and tight. If possible, it’s good to check both the connections at the battery and then trace the cables out to the ground point and the starter to make sure those connections are clean and tight too.
I recommend keeping a piece of emery cloth in your tool roll for cleaning up the battery terminals, but in a pinch you can scrap them clean with your pocket knife. Just make sure you don’t accidentally ground your knife to anything metallic while you’re cleaning the positive terminal.
So now that you’ve got a bike that is at least turning over, the next thing to check is gas. Usually just removing the gas cap and rocking the bike will let you hear if any gas is left in the tank.
Unless the gas is clearly at the top of the tank, I recommend switching to reserve just to be on the safe side. Many newer bikes no longer have manual petcocks, and instead have a gas light on the dash to warn you that your fuel is getting low. It doesn’t hurt to turn on the ignition and make sure that you haven’t been riding with the gas light on. If you don’t hear any gas in the tank and/or your gas light is on, it’s probably time to start walking to the nearest gas station.
If you’re confident that you do have gas in the tank and the bike still won’t start, you may not be getting fuel to your carburetor or injectors. On older bikes, it’s usually easy enough to pull the fuel line to see if gas is reaching your carburetor, but this is not often the case with newer fuel injected machines. Without having to take apart your fuel system, you can make sure that gas is getting to your combustion chamber by removing one of your spark plugs. If you just spent the last few minutes turning over the engine without it starting, then it should be flooded and the spark plugs will be wet with fuel.
Besides gas, your bike also needs air to run. If possible, remove your air filter and visually inspect it for dirt or debris. Mice and other rodents are know to make nests in airboxes, which certainly can block off air flow faster than a few stray bugs or leaves.
Once the filter is removed, try starting the bike to see if it will run without the filter. It is not advisable to run your motorcycle without a filter, but if it’s between walking five miles or riding five miles, I’d probably risk it.
Once you’ve verified that you’re getting air and gas to the combustion chamber, the final piece of the 4-stroke puzzle is a spark to get things going.
Start by doing a visual check of the ignition system, looking for cuts or burns in the spark plug wires, cracked spark plug boots, or loose coil wires. Then move on to making sure that your spark plugs are screwed in tightly and make sure your spark plug boots are pushed securely on the spark plugs and onto the coil.
You can check the operation of your plugs by removing one of the plugs and holding the electrode against the engine block while hitting the starter button. You should see a nice blue spark on a properly working plug.
If after running through this checklist you still have a motorcycle that won’t start, it’s probably ok to go ahead and call that tow truck. At least you’ll know that you’ve eliminated some of the basic problems and have a better idea what to tell your mechanic or where to get started when you get the bike home.