150cc cheap motor bikes

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1. 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

2. 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

3. The fact is, scooters are like any other piece of sporting equipment; they can be used and used safely, but you need to take proper precautions. Here are a few easily digestible guidelines for scooter safety that everyone who uses scooters should observe:

   1. Always wear safety gear: Helmet, Elbow Pads and Knee Pads. This is a small investment, but necessary- only about $30- can instantly eliminate almost two-thirds of possible scooter accidents. In many states, provinces and regions throughout the world, these are required by law!

   2. Always ride your scooter during the daytime. When it is dark out, there are just too many things that can easily upset your balance and cause you to fall. Therefore, no one should ride scooters at night.

   3. Scooters are not toys! Children who are under eight should always be supervised when using scooters. Almost a third of all scooter-related injuries and accidents involve children under the age of eight. As everyone knows, scooters are capable of traveling very quickly, and children that age do not always have the judgment or coordination to handle these high speeds.

   4. Always ride your scooter Off-Road & Stay away from all cars and any other vehicles -Cars and scooters don’t mix, especially for younger riders. Smooth, paved surfaces are best – avoid bumpy, uneven, wet or rocky ones. Schoolyards, parks, paved trails are examples of safe places to “scoot”! Stay away from Sand, Gravel, Water and Dirt ¨C Try to keep your scooter on smooth surfaces.

   5. Always observe the basic rules of the road anywhere you use scooters. As scooters can travel as fast as many other types of vehicles, motorized and non-motorized, they too must observe the rules of the road. These include:

   -Stop at every stop sign. Look left, right, and left again before proceeding.
   -Stop at the end of the driveway. Look left, right, and left before entering the street.
   -Use proper hand signals.
   -Obey traffic signs and signals

   Not Recommended

   -Avoid jumping off of curves.
   -Too much weight on scooter can bend or break the frame.
   -DO NOT ride on a flat tire. This is dangerous and will damage the tire and possibly the wheel as well.

   Mechanical Tips

   Check all joints, hinges and quick releases to ensure the scooter is properly assembled. Stop using the product immediately if any joint, hinge, or quick release becomes loose. Correct the looseness prior to resuming the ride. Maintain proper air pressure in the tires. Low air pressure induces extra rolling friction, reduces ground clearance, and wears the tires quicker. If the brake lever touches the handlebar grip, stop use of the product until the lever is adjusted.

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

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