50cc motor bikes for sale

2 Comments »

1. Using the headlight, electric start and alarm (if applicable) too much will drain the battery.
   Gas scooter does have the ability to charge itself but slowly. An optional charger can be for $25 at any local automotive stores.
   Most new scooters would have a full charge and it would be display on the battery gauge. But in time, the batteries would loose their ability to hold a full charge. That’s normal!
   Sometimes charging the batteries too much even when they are not low. Most of these batteries charging cycle are around 250-300 times.
   Sometimes store your scooter away for a long period would cause that as well. If the battery power drops beyond a certain point, the charger would not recognize it. Sometimes you could jump start the batteries by using a higher Amp charger.
   My Scooter Has Problem When Running at High Speed

   If the scooter idles well and runs fine at low speed, but has problems at high speed, the problem may lie inside the carburetor with the main jet. The fuel/air ratio at higher speeds is set by the jets inside the carburetor and to get at them the carburetor has to be removed and disassembled. This can be a tricky job as the parts are small and delicate. The good news is that these carburetors are quite cheap. You can get a new one for $60-$80, so if you can’t make your scooter run smoothly and you don’t like the idea of taking the carburetor apart, you can always replace it!

   ———————————————————————————————————

   Scooter Repair

   So you buy a scooter and something breaks. Who is going to fix it? Well, if you’ve bough in person from our retail store in California,? we have access to parts, shop manuals and we will have mechanics trained to fix your scooter. All you have to do is bring them in.

   But what if you are located outside of California, we have a few suggestions for you. You can try contacting local motorcycle (or better still, scooter) repair shops. If they are not very enthusiastic about working on a Chinese scooter, no worry! Have them contact our tech support department directly. We will make sure they will have the easy access to our spare parts and the technical support they need. Remember, we are the only company who actually carries all common parts in stock.

   150cc engine and transmission as used in many Chinese scooters

   You might also get some help from a lawn mower repair shop. They are used to working on small engines and the engine in a scooter isn’t all that different from the engine in a lawn mower. You can also try snowmobile and ATV repair shops.

   CVT (transmission) belt. Price ~ $40. Belt life anywhere from 2500 to 10,000 miles

   It’s not a bad idea to keep a few spares (such as a spare spark plug and CVT belt) on hand, just in case you need them (and eventually, you will). It’s a good idea to remove the CVT cover on your new scooter and read the number on the belt BEFORE you need to change it. Belt sizes vary, even on the same nominal scooter “model” and by the time it fails, the size markings may have worn off! The belt size is usually three numbers such as “835-20-30″. This would mean the belt is 835mm long, 20mm wide and has a cross section with a 30?? bevel angle.

   The best way to avoid needing repairs is regular maintenance, which means changing the oil regularly, changing the fuel filter and spark plug at the proper intervals, checking the CVT belt and air filter, checking the tires and going around the scooter at least once a month and making sure that all the bolts are tight (especially the bolts holding the muffler on). Use the recommended grade of gas (usually higher than 90 octane for most Chinese scooters) and add fuel stabilizer if the scooter isn’t going to be driven for a while.

   Though you won’t find individual repair manuals for every different Chinese scooter, they are all pretty similar and many use the same engines and transmission parts.. There are a couple of books which may help. The Haynes guide is probably the best general reference for the repair of “generic” (i.e. Chinese) scooters. The “Complete Idiot’s Guide to Motor Scooters” is pretty basic and really doesn’t give much detailed information, though it’s not a bad introduction to scooters if you really know nothing at all about them.

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

2. 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

RSS feed for comments on this post. TrackBack URL

Leave a comment