Yes.
Yes.
Yes.
Check your spark plug has spark. If so, spray some starter fluid into engine then try. You can find repair manuals for many types of mopeds at Mopedarmy.com.
It's either fuel, spark or compression. If the engine has all 3, in the proper order and quantity, it WILL run. So start by checking the easiest first; get a can of starting fluid, remove the air filter from the throttle body and have a helper try to start the engine. As soon as you hear the starter engage, start spraying the starting fluid into the air intake. As soon as the engine starts (or when the helper stops attempting to start the engine), stop spraying the fluid. If the engine started, you have a fuel delivery problem. Check the fuel pump, injector, fuel filter, fuel pump fuse... all that. If the engine didn't try to start, run a compression test. If you have low or no compression, rebuild the engine. If the compression is OK, check the spark. Lay a sparkplug on some GROUNDED metal part of the engine and connect a sparkplug wire to it. Have the helper try to start the engine again while you're watching the sparkplug. You should have a strong spark at the plug. If you get no spark or if you have a weak spark, that's your problem.
Does it have: fuel, spark, compression?
it can have spark & fuel pressure ;But if the brains bad the injectors won't open up, To test it spray alittle start fluid and if it starts its the brain.....hope this helps.......
the spark plug provides the spark necessary to ignite the fuel and air in the engine, which allows your engine to run. without spark plugs, your engine wouldn't start.
there are 2 main reasons 1 the engine is not getting enought petrol 2 spark engine is not getting spark this is probley the cause the main thing that goes wrog with the spark is the ht coil replace this and the spark plug and your engine should start
Try a little starting fluid. If the engine briefly starts with starting fluid, you have a fuel delivery problem. Check the fuel filter since it's easiest and least expensive. If that wasn't the problem check the fuel pump. If it didn't start with starting fluid, check the spark. Pull a plug wire, connect a spare plug and set it on a metal part of the engine. Have an assistant try to start the engine while you watch the plug. If you don't get a nice hot spark you need to repair something in the ignition system.
An engine which cranks but will not start is not receiving enough fuel or has no spark. A clogged fuel filter or bad spark plugs often cause this problem.
Does it have fuel, spark, compression?
Engine needs fuel, compression and spark. You are missing one or more of those.
It could be depending on what type of 90cc engine it is :shear key in fly wheel warn or slightly sheared timing chain out of time (check timing.)
engine have spark and fuel pressure and still will not start