When no fuel pump noise, bike wont start

[bikeissues]

hi,

 

keeway 125 superlight

2021

fuel injection model

 

main journeys are to work and back - 16 mins (7 miles) one way

 

arrived home on bike , no issues, next day cant start bike

i have a green neutral light, and the bike cranks over from starter

the battery seems ok, present voltage off bike was 12.3v

i have turned the key in all positions and moved bike around using steering lock on both sides

used gear box to go up and down gears and found neutral ok.

 

also made sure bike was on center stand and side stand was up.

 

when you turn the key to the "on" position sometimes you hear a noise which i think is the fuel pump.

It has a whining noise for a set time of 3 secs.

 

i also hear this noise if the key is "on" position and i move kill switch from "off" to "on"

when the kill switch is in the "off" position no noise.  this i believe is normal.

 

for some reason at times when i turn the key to "on" position i dont hear the fuel pump and im unable to start bike

even if i click the kill switch from "off" to "on",  no difference, no fuel pump noise.

 

at other times it feels like the fuel pump plays for 3 lots of 3 seconds one after another.

 

what could explain the lack of fuel pump on occasions which seems to lead to none starting bike.

 

thanks

 

 

 

 

 

Edited April 19, 2024 by bikeissues

[Mississippi Bullfrog]

12.3v is not OK for a battery. That is showing it's discharged.

 

Give the battery a trickle charge then try it. 

[bikeissues]

ok, forgot to say this is a 125 uk model, all original.  it has original battery still, never been charged.

I guess the battery could be of concern knowing the bikes age.

 

Also i think this model uses the lights all the time so another nit on battery.

 

today i did order a trickle charge battery charger to see if it makes any difference as i thought messing around with bike

trying to get it to start i might flatten the battery.  

 

i did measure the battery off the bike so i presumed as it was 12v+ it was fine but perhaps things are different once load is added.

 

Can you measure the battery output on the bike with all connected?  

 

 

 

 

 

Edited April 19, 2024 by bikeissues

[Mississippi Bullfrog]

You can have a battery showing good voltage but that collapses under load. Even a small load will do it so you could test with a spare headlight bulb. 

 

A 12v battery is really 6 2.1v batteries connected in series. So the minimum reading you're looking for is 12.6v. 

 

Lead a I'd cells don't like being discharged so if it's 3 years old and the bike has been standing the battery is suspect. 

 

At rest you want at least 12.6v. When running you want around 14v. If you check a battery shortly after running it ought to be around 13.5v. 

[Tinkicker]

Learned this voltage ditty as an apprentice at college 40 years ago...

 

12.7.  Im in heaven.

 

12.5.  Im still alive.

 

12.1.  Much work needs to be done.