150cc motor bike for sale

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1. Troubleshooting

   My Scooter Won t Start

   To start a scooter needs three things:

   Gas
   A spark
   Cylinder compression
   If your scooter won’t start it due to one of the above not being present. Before you start troubleshooting, make sure there is gas in the tank by actually looking into it. Don’t just trust the gas gauge!

   Most scooters have four things that need to be done before they can be started with the electric starter:

   The ignition has to be turned on
   The kill switch (usually near the right grip) has to be in the “on” position
   The rear (left) brake lever has to be squeezed.
   The starter button must be pressed.
   Some scooters may have other interlocks on the front brake or the center stand. Check your owner’s manual to make sure that you are doing all you need to?? complete the electrical circuit which enables it to start.

   If the scooter doesn’t turn over when you’ve done all the required operations, there’s an electrical problem with the battery. Make sure the battery is charged. If it is, make sure the fuse hasn’t blown. If it hasn’t, check to see if you are getting voltage to the starter motor terminals. If you are, the starter motor is likely defective. Many scooters have a kick start (see your manual). If the battery is OK and the starter motor doesn’t work, try kick starting it. It’s usually not too hard. My scooter usually starts OK on the 2nd or 3rd kick.

   If the scooter does turn over but still doesn’t start you have to check for a spark and make sure gas is getting to the engine. To check for a spark, remove the spark plug from the cylinder, hold the tip of the plug against the cylinder head and crank the engine. You should see a spark across the gap. If you don’t, there’s a problem with the ignition. Could be a faulty coil or electronic ignition module which will have to be replaced, or it could just be a lose wire.

   If you do have a spark, you need to check the gas. Make sure there is gas in the tank first! If there is you need to check the fuel valve. Most scooters use a gravity fuel feed by locating the fuel tank higher than the carburetor. The fuel usually then flows through filter and then through a vacuum operated valve. The valve has three hoses connected to it. One if from the fuel tank and is for the gas going in, one is connected to the carburetor and is for the gas coming out and one goes to the engine manifold which provides a vacuum. If you disconnect the hose from the carburetor, fuel should run out when you crank the engine (be careful to catch the gas if you do this and don’t do it with a hot engine). If you don’t see gas the fuel valve may be faulty. You can try applying a vacuum to the control port of the valve and see if the fuel flows. Sucking on the line is one way to do this (but make sure it’s the vacuum line, not the gas line if you try this!).

   If you are getting a spark and you are getting gas to the carburetor and the engine is turning over on the starter OK, it’s possible that the electrically operated automatic choke has failed. It’s supposed to operate when the engine is cold, but if it’s stuck or burned out, the mixture will be weak and the scooter probably won’t start. The automatic choke is usually a black cylindrical object attached to the carburetor with a couple of wires coming out of it as shown on the left. It’s the only electrical powered component attached to the carburetor, so it’s usually not hard to spot. If you have a voltmeter you can measure the resistance across the leads of the choke. It should be somewhere in the region of around 10 or 20 ohms. If it’s an open circuit, it’s burned out and will need to be replaced. If it seems to be OK it may be stuck, or the wiring to it may have a problem. Check to see that it’s getting voltage.

   It’s also possible that there is a problem with the carburetor and if so you may need to remove it and clean it out. If the scooter has been sitting for a few months with gas in the carburetor, the gas may have evaporated and left a sticky “gum” behind that will prevent the carburetor from working properly and which must be removed.

   If the automatic choke is OK, the starter cranks the engine, there’s gas and there’s a spark then there may be an engine problem. You need to check the cylinder compression. You need a compression tester to do this. It screws in instead of the spark plug and measures cylinder pressure. When you crank the engine you should see a reading of around 150 psi or more. If it’s 100 psi or less there’s likely and engine problem (bad valve, bad piston, failed piston rings) which will need the engine taken apart to find.
   Probably the most common problems are a dead battery or carburetor problems due to bad adjustment or build up of gummy deposits. Carburetor problems usually come on slowly though. If a scooter is OK one day and refuses to start the next day, I’d first suspect an electrical problem.

   Comment by master — 05/12/2010 @ 3:15 pm

2. Now you can look for “assembly instructions”, which with the average Chinese scooter will be one sheet of paper which says something like “attach the rear view mirrors, install the battery, etc.”. You may have to use some ingenuity to figure out how to do all this, but it shouldn’t be beyond the capabilities of any amateur home mechanic. It may help if you have a decent socket set, screwdriver set and set of metric wrenches since the supplied “tool kit” usually leaves much to be desired.

   Batteries are typically shipped “dry” with the acid in a separate container. You have to add the acid to the battery and leave it for 30 minutes of so before using it. After this it shouldn’t need to be charged to start the scooter.

   Once you have all the parts attached (and that will include at least mirrors, seat, rear carrier, battery and floor mats), and you’ve waited about 30 minutes after adding acid to the battery, you’ll be ready to start the scooter.

   If you just put fuel in the tank, you may have to crank it quite a few times before it starts since the fuel has to get to the carburetor and fill the float chamber before gas gets to the engine. You can prime the carburetor by disconnecting the fuel hose from the vacuum valve and connecting it directly to a small funnel and adding a little gas, then reconnecting the fuel line to the valve and adding fuel to the tank. However if you don’t know what you’re doing, just try to follow whatever instruction came with the scooter. Use premium gas. Most scooters seem to be setup to run on 91 octane fuel.

   The final point of assembly is to check everything. Check the tire pressures, check that every bolt and nut you can see is tight, especially the ones holding the exhaust and muffler – and the wheels! Look around for lose wires or rubber hoses that don’t seem to be attached to anything.

   Comment by master — 05/12/2010 @ 3:15 pm

3. Small 50cc scooters (“Mopeds”) are good for about 30 mph, maybe 35 mph in some states without speed restrictions. They will just about keep up with urban traffic, but you have to ride them WOT (Wide Open Throttle) do to that. This can be good for novices and young riders because in most of states the rider does not need a motorcycle license to operate a 50cc less scooter, but the inability to keep up with faster traffic can sometimes be a hazard as cars try to “squeeze” past you when there really isn’t room.

   150cc Chinese scooter. It might look fast, but it’s not really very happy above 60 mph. Mid sized 150cc scooters are good for 55-65 mph, though with a long enough run at it they may get up to 65+mph, especially if there’s a tail wind or slight downhill grade. 45-50mph is enough to keep up with most urban and suburban traffic, though it’s really not enough to flow with the traffic on a freeway, where speeds of 65-75mph are more normal. We?ˉd certainly recommend a 150cc scooter over a 50cc scooter for commuting unless you live in Manhattan. Most of the 150cc scooters cruise quite comfortably at 45-50mph.

   If you want a high speed machine, you would probably be better off with a motorcycle.? 250cc scooters are just about OK for freeway use and should be able to cruise at 60mph and get up to speeds of 70mph or more if pushed. We wouldn’t recommend riding anything less than a 250cc scooter on the freeway, you might want to check on our 300cc motorcycle that is listed on our website.

   What MPG Does a Scooter Get?

   This depends mostly on the engine size. The smallest engines are typically 49cc and they can give up to 90 mpg, depending on what type of riding you do and how much you weigh. Obviously if you weight 300lbs and do mostly short “stop and go” trips you’ll get a lower mileage than if you weight 100lbs and travel mostly on long trips at modest speeds. At the extreme, we’ve seen figures of 110-120 mpg for 50c scooters when the rider was trying their best to drive as economically as possible.

   Comment by master — 05/12/2010 @ 3:15 pm

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