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It won't start
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Don't you just hate it when the weather
turns out great and you want to roll out the bike and it doesn't start? Yeah,
we all at one time have experienced this and didn't like it. Basic
troubleshooting requires little in the way of tools and skills. However, you
should at least feel comfortable removing a spark plug, draining a carburetor
and using a voltmeter or test light. Buying a factory service manual or its
equivalent is not only a good idea, but will be invaluable aide if you plan on
keeping your bike past the warranty expiration date. Internal
combustion engines need three things. They must have good-quality fuel,
compression and a spark delivered to the compressed fuel/air mix at the
appropriate time, or very close to it. Given those three items, an engine will
run. Since the majority of you probably own bikes that start with a button, the
fourth item you'll need is enough electrical energy to spin the starter.
I hate it when you press the little black button and nothing happens! You
did follow the correct starting procedure, didn't you? Every motorcycle has its
own starting drill. Many require that the clutch be held in, whether the bike
is in gear or not, and some want the bike to be in neutral anytime it's on the
kickstand. Before you panic, verify the starting procedure, especially if it's
a new bike that you're not entirely familiar with. It may sound obvious, but
make certain that someone hasn't moved the kill switch to off, especially if
you've had all of your friends over drinking beer and admiring your motorcycle
or you have little urchins running around who love to sit on motorcycles when
mom and dad aren't watching.
If everything is in order and she won't
even spin, the most likely cause is the battery or something that's preventing
the battery from doing its job. Most of us are familiar enough with the
conspicuous signs of a dead battery: dim lights, a weak horn and slow or no
starter activity. Push the horn button; if the horn sounds anemic, the battery
is probably discharged. If that seems to be the situation, it's time
to charge or possibly replace the battery. Before you do, though, check the
battery terminal connections. It's possible that the terminals are loose or
corroded, and a good cleaning and tightening are all they need. Follow that up
with a voltmeter reading across the battery terminals, or a hydrometer reading
of the cells. If the voltmeter reads less than 12.5 volts (no load) or 11.5
volts with the lights on, or the hydrometer reads less than 1.265 (less than
four balls floating), it's time to service and recharge the battery.
 Checking the Battery with a Hydrometer. |
Charging the battery is going to take some
time. You may be tempted to try and jump-start your bike from your car or a
buddy's bike. It can be done, and in the past I've certainly done it. However,
many late-model motorcycles, particularly those that are fuel injected, utilize
some sort of microprocessor. Computers are highly sensitive to voltage spikes,
and nothing causes a spike like a jump-start. If you're unsure about the
jump-starting procedure for your bike, play it safe and sit this dance out, at
least until you can verify that jump-starting your bike is safe.
Obviously, the worst-case scenario is going to be a good battery and no action
at the starter motor. If that turns out to be the case, you'll need to do some
troubleshooting. Start with the simple things. Likely trouble spots
include a blown fuse, or a malfunctioning kickstand safety switch or
clutch/starter interlock switch. If the culprit is a blown fuse, replace it
with one that carries the same amperage rating and give her another try. If the
fuse blows again, you've got a dead short somewhere, which will need to be
repaired before you go much further. If one of the switches is suspect, they
can be bypassed with a jumper wire to get you back on the road
 Key is on, and the bike is in
neutral. |
 The kill switch is in
the run position... |
 The fuel petcock is
in the off position.... |
If the bike turns over normally without
laboring, chances are pretty good that the problem lies in either the fuel or
ignition system, particularly if the bike was running fine when it was put
away. As above, start with the easy stuff. Did you do anything to the
bike before putting it away that may have created a problem? For example, if
you pressure washed the bike, water may have entered the ignition switch, plug
caps, kill switch or kickstand safety switch. A shot of WD-40 or some other
moisture-displacing lubricant may solve the problem. Is there fuel in
the tank? Sure, you know there's plenty in there, but play it safe, pop the cap
and take a look. If you can't see it sloshing around, the tank might be empty
after all. Of course, on bikes with under seat tanks and remote filler caps,
this check won't be possible. If the bike has a petcock, an item that seems to
be found less and less these days, place it in the reserve or prime position
and try starting the bike. Still won't start? The two most likely
suspects: Either fuel isn't reaching the engine (assuming that the tank is
full), or you've lost the spark. If the bike shows absolutely no inclination to
start, I'd head for the spark plugs. If the bike coughs and sputters, I'd lean
toward the fuel delivery side. But don't forget, fouled spark plugs will
certainly make a bike hard or impossible to start, and may mimic a fuel
delivery problem. Actually, since I'm pretty lazy, I always check the easiest
thing to reach first.
To check the spark, remove one plug from the
engine. If it's wet with unburned fuel, it's a safe bet that the plug is either
fouled from too much choke (yes, I know they're not "chokes"!), or you've lost
the spark. If the plug is fouled, give it a thorough cleaning, insert it back
into the cap and lay the plug on the cylinder head or engine case. Make sure
there is no spilled fuel in the vicinity. Crank the engine over while observing
the plug. There should be a nice fat blue spark crackling from the tip. If
there isn't, try a new spark plug, a known good one, before condemning the
ignition system. If no spark is forthcoming, you'll have to decide
how involved you really want to get in the troubleshooting process. The problem
could be as simple as an unplugged or dirty connection, or it could lie in the
ignition module or signal generator. If you have the tools, skills
and inclination to track down the problem, go for it, but for the rest of you,
this is another instance where I'd recommend you call the dealer and make a
service appointment. Be forewarned that electrical problems on modern bikes can
crop up suddenly, and can take some head-scratching to find. Ok you
have a nice fat blue spark; the next step is to check fuel delivery system.
Loosen the float-bowl drain screw and allow some of the fuel to run out. If
possible, catch it in a small container. If there is water in the fuel, it will
appear as globules. If water or lots of dirt is evident, drain the float bowls
completely, and allow them to refill before trying to start the bike.
If the float bowls are dry, or there is little fuel in them, the problem most
likely lies in the fuel delivery system. If the bike has a vacuum-operated
petcock, turn it to prime. If fuel starts to flow, the problem lies in either
the petcock or the vacuum line; a little detective work should pinpoint which.
If the petcock is manual, move the lever to reserve. If fuel flows,
you're either low on fuel after all, or the petcock main feed is plugged or
damaged. If no fuel flows, remove the fuel line at the petcock and try
everything again. If fuel flows from the petcock but doesn't reach the float
bowl, the problem is most likely a plugged fuel filter or line. Some
motorcycles, primarily those using remote fuel tanks or fuel injection, use an
electric fuel pump. Testing procedures for these vary, so you'll need to refer
to the shop manual for the correct method. But as a rule of thumb, you can test
the pump by one of two methods. Start by disconnecting the fuel line from the
carburetor or injector. Place the open end of the line in a container and turn
the key on. Fuel should gush out of the line. Some pumps are only activated
when the engine is cranking or running. If the first test didn't produce any
results, try cranking the bike for a few seconds to see if things change.
If neither method produces any results, chances are that the fuel filter
is plugged, or the pump or the circuit controlling it has failed. If you
suspect the pump itself, check the electrical connections and the fuse that
feeds it before condemning it. Bear in mind that troubleshooting a
fuel injection system requires some very expensive and specialized equipment.
My recommendation here is to tread very lightly-this is really
trained-technician territory. No less a consideration is safety. FI systems
work at extremely high pressures; get in front of a working injector nozzle and
you're going to be in a world of hurt. Injectors rarely fail. It's
usually the pump that's the troublemaker. Most FI pumps run for a few seconds
whenever the key is turned on to pressurize the system. Get in the habit of
listening to yours when the bike is healthy so you know what it should sound
like. If she won't start, take a good listen. Can you hear the pump run? If
not, check the pump fuse. As a last resort, try cranking the engine
while you spray a very brief burst of carb cleaner into the air intake. If it
catches and runs, you know there is some fault in the fuel injection system.
Determining where it lies will most likely call for a trip to your favorite
shop. If you've got good spark and fuel and she still won't start,
you'll need to do either a compression or leak-down test to discern where the
problem might lie. In the real world, sudden, overnight losses of compression
are rare. However, if the bike has been sitting for any length of time, then
all bets are off. If you don't have the proper test equipment, a
quick and dirty test is to hold your thumb or finger over the spark-plug hole
and crank the engine. If you can feel noticeable pressure, the compression is
probably enough to get the engine started. If not, it's time to do a proper
check before going any further. Modern motorcycles are notoriously
reliable, but things do go wrong. In my experience, many no-start conditions
turn out to be something relatively minor-usually no fuel or a bad connection
somewhere that kills the ignition. Remember, engines need spark, compression
and fuel to run. To get back on the road, all you have to do is figure out
which one is missing.
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