Yamaha City 125cc Scooter problem starting

I have a Yamaha vity 125cc moped that been having problems starting up I’m on it daily for work but there’s been a couple of times when going to start it and it don’t start. Sometime when turning the key you hear a huming sound and the engine light comes on so I know it’s not dead but on sunday I got on my bike turned the key the engine light came on but no humming noise so when I tried the engition switch it was trying to start but just wouldn’t so I tried it a few more time and the sound from the engition switch started cutting out and at one point I press the switch and nothing was happening. Yesterday my bike was sitting over night I went out to the shop about 15mins drive from my house after 10mins in the shop I got on my bike tuned the key engine light came on but when I pressed the engition key it tried to start but just wouldn’t start running I ended up pishimg my buke for 20mins in the sun trying to start it evey 5 mins in the end I slaped the front panel near the light a little hard like 3 times out of fraustration tried it and got running.

To me it can’t be the battery because for one the engine light come on when turning my key plus the battery only charges when the bikes running so it so on Sunday if the batter was dead it would charge up sitting on my drive way all night.

Spark plug I’m not sure about again to me the bike does start so unless the connector is loose.

Engition switch I can’t see it being that as it works and yes it did cut out which is why at first I thought maybe the battery was about dead but it can’t be…someone told me the fuse on the battery, loose wiring or the carbaretor but I don’t have a clue mainly because now since all this I’ve got the bike running 3 times now and everything seems fine the engition light comes on with that humming sound after turning my key and when I press the engition switch a few kicks and boom it starts so if anyone has any ideas what the problem was or is and will it happen again if so what should I do as I’m stumped for ideas. Thanks

I doubt this will help much b/c my experience on this subject is 40 years old, but as a teenager I used to ride 2-stroke moto-cross style bikes in that displacement range, and when mine wouldn’t start it was usually either the spark plug was oil-fouled, or the points were out of adjustment.

I am sorry Nathan but trying to understand your post made my head hurt. Get a new battery and see what happens and keep your next post short , simple and clear.

I wish I had a dollar for every time I heard “It can’t be the battery because” and it turned out to be the battery. Do you at least have a voltmeter? If you don’t, either get one or go soeplace and get the battery and charging system tested. Some auto parts stores do it for free. I don’t know if they will do it for a moped but a simple phone call will find out.

1 Like

When I had my Moped back in 1964, every time it wouldn’t start, I’d have to pull the spark plug and clean the fouling. I never knew exactly what I was doing wrong and no suspect maybe I was not mixing the oil in the fuel in the correct ratio. Just a guess on my part from how many years ago as a kid. If it doesn’t start though, pull the plug and clean or replace then try to start it again. If it starts you know where the problem is.

1 Like

The Yamaha Vity has a 125cc air cooled two valve four stroke engine and I’m pretty sure it has pointless electronic ignition. It’s really a scooter and not a moped. A moped is a motorized bicycle that can be pedaled like a bicycle in addition to being powered by the engine.

Yes, it can be the battery.

The Yamaha Vity has electronic fuel injection so the humming noise you hear when you turn on the ignition is the fuel pump pressuring up the fuel line to the injector. It usually only lasts a second or so and stops when the correct pressure is reached, then as the engine runs it turns on and off according to fuel need.

Don’t overlook the obvious. Make sure the kill switch on the handlebar is not turned to off. Don’t laugh, I’ve seen it happen, people hauling their bikes to the dealer only to find someone turned the kill switch to off. I can name names.
There is another kill switch on the bike and it’s the sidestand interlock. Make sure the sidestand is going up all the way. It’s possible that when you tried to push start that bike, the jiggling caused the sidestand to go up all the way and the interlock then allowed you to start the bike.
Trying to push start this scooter is a waste of time since it has a centrifugal clutch that is disengaged when the engine is not running or idling.


Yes it CAN be the battery. A light coming on means nothing.

I’m amazed that a 125cc engine has an electric starter. If properly tuned up a motorcycle should start on the second crank if not the first cold or hot. And if I’m deciphering the OP correctly the battery is a problem.

I think Nathan must live in Europe because the Yamaha Vity 125 is not sold in the States. Every search I have done on the Vity and its specs has the prices in Euros or Pounds.
The US market gets a 125cc scooter called the Yamaha Zuma, which may be the same bike that meets US standards.

If it is a weak battery, hitting the start button will make relay clicking noises as the relay chatters.
If absolutely nothing happens when you hit the start button, look for electric problems.
My EFI Kawasaki makes a brief humming sound when the ignition key is turned on. More like a whirr than a hum. That’s the fuel pump pressuring up the fuel line.

Believe it or not, it’s hard to actually buy a kick start motorcycle today. At least the old school Japanese bikes kept the kick starter even though they had electric start. The last kick start, and kick start only bike I owned was a Yamaha SR500, big 500cc one cylinder engine, like kicking over a Harley Sportster.
A kick start is an added cost that raises the msrp. Once they started putting electric starters on them, they started leaving the kick starters off, which means that on a automatic clutch belt drive cvt, you are totally dependent on the electric starter.
At least you can push start a conventional six speed manual if the battery is low.

I know my apologies hahaha reading back at it now I see what you mean. I actually done this post around 4am yesturday morning just after finishing my 10 night shift so I was half asleep…funny enough I’m replying to you now at 4am in the morning I’ve just finished work but this time I’ve proof read it so it makes sense hahaha

I am I’m from the united kingdom. when I search for my bike online I seen the Yamaha Zuma and I believe your wright they are the same.