150cc chinese mopeds

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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 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. 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

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