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Discussion Starter #1
Ok I recently picked up a pretty 1982 Honda nighthawk. It's a 650c. It ran perfectly when I picked it up, but owner said he recommended a carb cleaning. I drove it home no problem, then the same evening tried starting. It wanted to die without choke, any throttle killed. Well after a few times trying to get it to idle; it sputtered out and stopped starting altogether. It rolls over, just doesn't start. I replaced spark plugs. Put in fresh fuel (with seafoam), and gave the battery a good charge. As of this morning there's still no start.
Ok. I'm 100% not mechanically inclined but wish to learn and handle this thing. However am struggling to find comprehensive help online. I believe I need to clean the carbs. What if like to know is a nice list of supplies I'll need first. (Tools, chemicals, etc.)
Any other suggestions are GREATLY appreciated. Thanks for any help guys :)
Looking forward to being a part of the club.
 

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Clean me

June 015 issue of Motor Cyclist, page 88. Article, How to clean a carburetor.
It is very basic.
Page 78, an article on fuel.
Better still is my Clymer manual for my 79 Yamaha. It has blow up pictures of all the pieces. I would suggest finding a manual for your bike. I got mine used.
For another bike I snapped a picture with my phone, of the page on carburetors.

Unkle Crusty*
 

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Diagnosing nostartee

IF your bike won't start you begin by diagnosing whether it's not starting for lack of fuel, spark, or compression.

It could be something as simple as being out of gas or having the engine kill switch flipped, kickstand down, etc.

REPOST: DIAGNOSING NO START ISTUATIONS

Do you have a no-crank or a no-start condition? For NO CRANK, go to:

http://www.motorcycleforum.com/showt...ght=diagnosing

For "No Start...."

First, check the fuel tank make sure it's not empty. Or just add a gallon of fresh and then you don't have to think about whether there's "enough."

Next, get a can of starting fluid (ether), brake cleaner, any FLAMMABLE aerosol...

Take off your air filter, spritz some in as you crank the bike. If it catches and starts, you've got a lack of fuel problem. As long as you keep spritzing the motor should continue to run.

If it doesn't start on faux fuel, stick a screwdriver into the spark plug boot and hold it 1/4" from the plug as you or someone else cranks. If you don't see a spark, you've got an ignition problem.

Do TRY and hold the screwdriver by the insulated handle....

You can also use any of a dozen different spark testers, or a timing light, anything that confirms existence of spark....



Got spark but still no start? Pull the plug(s) out. If its wet with fuel, dry it in the sun or with compressed air. Wire brush any carbon off, check the gap as long as you've got it out.

Check the gap as long as you've got the plug out, or replace it with a new plug, and check the gap on the new one ESPECIALLY if some fool tells you they come pre-gapped!

with the plug still out...

Put your finger over the hole and crank. You should feel it trying to blow your finger off the hole as it comes up on the compression stroke. No compression? Try a squirt of oil down the hole and crank again.

Still no compression? Possibly a stuck valve!

Air, fuel, compression, well-timed spark, those are the things an engine needs to start.

Determine which one you don't have!

Other possibilities: Water in bottom of tank....only THINK your engine is getting "fuel"..
 

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Discussion Starter #4
Interesting; I've had the kickstand down trying to start but it's been in nuetral, would that keep it from starting?
 

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Side stand

Check and see if there are any wyres going to the base of the side stand. If there are not any, no worry. Engines will usually start with the side stand down, but will quit when you put them in gear. But, that is a feature on newer bikes.
I doubt whether you have wyres to the side stand or clutch lever. But if you do, they can short out and prevent spark. remove a plug and check for spark.
Is the engine turning over on the electric start motor?

Unkle Crusty*
 

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Good

I would like to clarify tho. When you say it is rolling over. I would like to know that it is a result of you turning on the key and pressing the start button. Also assuming that fuel is flowing, and the gearbox is in neutral.

If the above is correct then I would check for spark.

Rolling over is a term that might apply to push starting a bike.

Unkle Crusty*
 

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first you need to understand carburetion.

gas is mixed with air and vacuum in the proper amounts to create volatility, and any too much of any of the 3 will cause the gas to burn slow, fast, or not at all. When fuel is made this way, it is very very efficient, and so the mixing must be controlled. It is done with carburetion. the octane fuel is injected into a chamber with flowing air in it. the flow causes vacuum in the chamber that forces the fuel and the air to supermix, creating a form of combustible, that is a material that is flammable.
 
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