If you own a scooter and cannot get it to start-up, you know how absolutely frustrating this can be. If you find you are in this standing keep with us for valuable tips and insight.
Check to see whether your exhaust pipe is blocked. Two stroke scooters are especially susceptible to this quandary. Over time, carbon and the unburned fuel and oil mixture build up and clog the exhaust pipe. Blockages in the exhaust pipe will adversely affect the performance of your scooter, or trigger it to not run at all. It is not easy to say whether the exhaust pipe is congested. Removing it and starting the scooter is the easiest way to tell if it is bunged or not. The sound may be a little loud - two strokes may boom like a chain saw. If the scooter runs now that the exhaust is removed, you know where the quandary will be found.
Think back to when you drained the old gas. How old was it? Did the gasoline have an old smell? gasoline in a scooter left idle for a year or so will transform into a varnish-like substance. Then you have a lot of cleaning to do. The gas will generally evaporate, imparting a sludgy, substance in the gas tank,petcock, fuel line and carb that is similar to molassas. Completely flush the gas tank and lines with new gas.
If the gas tank is not too rotting or sandy, it may be ok to merely flush it out. Now put in some new gas. However, if you aren't positive how old the gasoline is, (even if it smells all right), drain the gas tank, carburetor float bowl, and fuel lines,and replenish with fresh gasoline. Some time ago I worked on an Hond 50 with quite clean-smelling gas. I could make it go with starting fluid, but I couldn't do it with existing gas. At last I had to drain out all the old gas and refill it up with new gas. After that, the scooter fired at once and ran well.
Take the fuel and vacuum lines from the petcock to the carb. Put an appropriate receptacle beneath the fuel line, and draw air on the vacuum line to the petcock, (if equipped with one), and witness how well the gasoline flows. There should be sufficient flow. A seep is not good enough. If you are able to get this flow, then you are alright. Flush the system by operating a minimum of a pint of gas through it. If there is still no flow, it doubtless means your petcock is bunged. You will need to take it out and take it to pieces to clean it. Return it with attention on the gas tank or the gas might leak. start the scooter after repairing everything. The gas wishes a few seconds of cranking to make its way from the gas tank to the carb. If you are timely, it may start up right away.
If you still have problems at this point try the following. install a new spark plug, particularly if it is a two stroke engine. The air filter should be cleaned or replaced when required. The carb, air cleaner, and exhaust system should all be inspected and adjusted to work together. If you change any of these items randomly or haphazardly, most scooters will not run right.
Check all the connections again. After that, crank the engine for 10-15 seconds. Is it activated? Do you hear any popping sounds, as though the engine is attempting to run? Do not direct the throttle while cranking; many scooters do not start when you do this. In most cases, for Honda scooters if you utilize thethrottle just when the engine catches, they seem to fire-up easier. near all Yamaha scooters have to idle up awhile before you can use the throttle. If it seems the scooter is catching, but still will not start, wait about fifteen seconds and try again.
If the speedometer is not running, it's mostly because the speedometer cable is busted. check it about 5-6 inches from its connection at the front wheel. This is mostly where it breaks because of the twist in the cable and being vulnerable to the elements such as water and dirt close to the front wheel. New speedometer cables are inexpensive (generally under $20) and you can return them easily.
Now inspect the center stand of your scooter. Getting it parked on this stand can be hard save if you practice. It's all in the procedure. Even the center stand of a large motorcycle can be deployed by a small person if correct method is followed.
Now you are ready to drive and may want to know how to raise the top speed of your scooter. This question is asked most regularly about the 50cc scooters, but also can be asked about the better scooters as well. The question that is of most importance is, how much money are you disposed to consume? If you own a 50cc, and you desire the top rate to go from 25 mph to 50 mph, you might want to think basically ofbuying a better scooter. As you encourage the acceleration, you will discern that the brakes, suspension, and frame are not up to par. It is fairly expensive to return all the parts. If you merely want a little better speed, modifications to your 50cc scooter's carburetor, exhaust system, and the variator may result in better performance. possibly you can get a big bore kit and this will promote the engine displacement from 50cc to approximately 70cc.
Generally, adding a performance racing clutch or performance variator is the easiest thing to do. They may impart you with better acceleration and/or advanced speed.
You can also acquire a new performance carb, a new exhaust system or both. These two components (and doubtless the air box) would need to be replaced together for optimal performance. mainly, the engine is an air pump. You get more power when you move more air through the engine. By adding a better carburetor, you will draw more air and more fuel into the engine. By not altering the air box, you are restricting the total of added air. You also contain the total of air out of the engine if you neglect to return the exhaust system with one that is either better or freer flowing. Additionally, simply altering the carburetor changes the fuel to air ratio inside the engine. The changes that you make may or may not be liked by your engine. For example, the new carb should give you more top end power, but may lead to ignition problems or the performance might be good at low RPMs but modest at higher ones. It can be hard work to modify your scooter to get the best performance. endeavor to purchase a kit that includes a carb, air box and an exhaust system that are all designed for your scooter. It will make things much less obstinate. lastly, use the big bore kit. This will encourage the torque and acceleration, but will not increase the top speed unless gearing modifications are made. There aren't very many performance parts for large scooters readily available in the United States (except for certain new scooters).
Still want more performance? You can try some of the additional tweaks to additionally perfect your gas scooter. You can try to get another drive belt. This will give you a little lead on the mph; new belts ride higher in the pulleys. You can also alter your roller weights (you can use heavier rollers for more top speed), adjust your valves, install a new air filter, and keep your tires pumped right.
Next test your idle. Is it too high? This can be caused by a throttle cable that is too stiff or not routed right. It could also show that you need to twist the idle screw on the carb the opposite direction ~1/4 turn. A vacuum leak may also be a grounds for a high idle. The rubber manifold connecting the carb and the cylinder head may crack after a while. attempt to start the engine and spray some water around the carb, manifold and vacuum hoses. If there is a reduction in the idle, it means that there is a vacuum leak somewhere.
Finally, one last thing to consider is elevation. This may not happen very frequently, but it's good to know besides. Your scooter will have trouble getting enough air at heights above 4000 feet. You will need to place a minor main jet in the carburetor. A good statute to track is to decrease the size of the main jet by about 10 percent, and then see if that helps performance.
Hopefully these tips will help you enjoy your scooter for years to come. Don't give up, contact us if you have further questions.