Modern Vespa

My fly 50 usually runs great.
But yesterday i was on my way home from an interview and i pulled up to a light and it just quit on me. I tried to restart her and she wouldn't turn over. I thought i was the spark plug so i walked 5 miles down the street got a new one and put it in. Unfortunately it was not the plug so i checked the fuse next to the battery, that was fine too. I can hear the electric starter trying to work but its not turning over. Anyone have any insight? I already paid to get it towed back to my apartment, i really dont want to get it towed to the dealership next!!

thank,
-Fage'

Well, as you say the engine is not turning over - we can rule out things like spark and fuel as the likely problem. That leaves either an electrical problem or a mechanical problem in the starter. Check fuses, ground connection, and the like. How many miles on the scoot? Has the CVT ever been serviced. Belt dust can build up in the CVT and interfere with the starter engaging. Electrical problems such as the spark plug wiring, stator or CDI could case the bike to stall and not restart but I am homing in on the observation that the starter is not turning over the engine. What happens if you try to kick start the scoot? (presuming the scoot has a kick starter)

Check your battery. There may not be enough juice in it. Clean the cables. If that is good, it may be the Bendix is stuck and not moving out to engage.

it has 3800 miles on it, it was last serviced at 3000 miles, i dont know if they opened up the Transmission case, the last time i did that was about 2000 miles. I tried to kick start it and it wouldnt start. however i didnt try it witht he new spark plug.

Sure sounds like it your battery, check your horn, is it loud, your lights are they bright and your kill switch is it on or off.

IBKING

Hey Fage - did you ever get your sudden power loss issue resolved? Perhaps it's related to this and the details of that would help people diagnose your current problem. Or they're unrelated. Who knows.

IKBING, i dont think it is the battery, the lights are all come on and i can hear the starter trying to do its thing.

Xantufrong, yes i did solve that issue, i cleaned the air filter and havent had an issue since

Ah ok


So - you haven't actually said if you are getting a spark or not. Very easy to check and I think we need to know the answer before we speculate too far.

Does the plug get wet when it fails to start? If it doesn't then you aren't getting gas into the cylinder - carb needs cleaning or fuel tap isn't opening, or gas lines are clogged. Conversely, if you do have a spark but the plug is looking soaked then your engine is flooding.

Stupid questions.
a)Are you sure you didn't run out of gas?
b)Have you toggled the cutoff switch a few times? (perhaps it got bumped).

Remember there are only three things for an engine to run.
1. Spark
2. Fuel
3. Air

If the engine was struggling then we could look at air flow, however you didn't mention that. So let's look at Fuel.

--If there is fuel in the tank, then check the fuel lines for leaks and or kinks.

--If the plug is wet as xantufrog described then you have fuel to the jug.

Next. Fuel to the engine and the airbox/lines are not blocked, then it check the spark.

Yes, I know you said you replaced the plug, but did you follow the spark plug wire back and ensure it's seated properly on the mag? This could be as simple as a disconnected wire.

To check the spark. Remove the plug from the engine, reconnect the spark wire and hit the starter. And watch the plug for spark. !!!! Be careful not to touch the spark!!! Recommend holding the spark plug cable and not the plug itself.

Hope this helps.

At least it died on the way home from the interview.

Also remember your spark plug will need to be grounded, for it to make spark when out of the combustion chamber.

You can hear the starter do it's thing, but is it engaging and turning the motor over or just spinning?

its just spinning

The reason why I asked was because the motor will start easier with the starter than the kick start. The starter will take more power to operate than the lights will. There fore it may appear that the battery will have enough power but it may not have enough to start it. If you have a charger, put it on for 10 - 15 min. then see if that will work. If the starter isn't getting enough power, it won't engage the bendix. I have tried to start my scoot with the kick start a few different times and was able to start it only once.

Clean the connections.
Take battery out and do a draw down test on it.
May have to pull starter.

today i fiddled around a lilttle bit, here is wat i found out

1 spark plug IS sparking, i took it out and grounded it and it sparked right up.

2 I tested the fuel tap, it was giving me sufficient gas

on top of that im pretty sure its not the battery because i am getting a spark and i can hear the starter going. However i do not really hear the engine trying to turn over

How about the voltage regulator? That can cause those symptoms, i think. If i'm right my "teachers" will be proud of me.

where would i find that, and what would be the test for it?

Chances are your starter motor is crudded up- it's spinning, but not throwing the starter gear out to engage the crank. The quick (but not conclusive) test is to tap the starter while pressing the starter button.
Starter spinning (UPDATE)

Beg, Borrow, Steal, Buy a booster pack,
Hook it up to your battery, Start it up.

The LX/Fly/Derbi series scooters are notorious for not having enough start up juice.

Although, It shouldn't have quit on you after running,
What were you doing with it before you got to the stop light?

Was this a normal commute?

If it was, Then It could be something else more serious,
I'd take it in to the dealer then.

Before the light i had driven like 8 miles just fine. My normal commute is usually just 3 miles or so, but i have gone on some 40 mile rides on her before with out issue

Finally brought my bike to the dealer. they did a "carb overhaul" which basically means they took it apart and cleaned it. Now it starts just fine. Still kind of wonder what exactly what was the problem but i am back on the road!