Diagnosis please - Battery vs Reg/Rec vs Other
 

Bike hasn't been starting (other than jump / bumping it)

So picked up a multi-meter and took some readings -

Bike off - 12.5v
Try to start it (unsuccesfully) - 12.01v
Bump start it, idling with no lights - 14.5v
Idling, no lights, rev it to 5k, drops to around 13.8-14.1v
Lights on, idling - 13.8v
Lights on, rev to 5k, 14.2v

Bizarrely i noticed today, when riding home, that when i was sitting in traffic, lights on... if i revved, sometimes the lights seemed to get duller (ties in with the drop in voltage when revving above) yet other times it got brighter....

So, is my battery fubared or is it the reg / rec..... ??

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

Did you test with lights on hi-beam?

When you said, "try to start it", was the the voltage as it turned over or after you stopped turning the engine?

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

No just full headlights, not highbeam... and after i tried turning it over...

If i left the bike running for a few mins it then turned it off the reading was about 12.8v and gradually dropped to about 12.5 within about 5mins...

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

Sounds like the charging is off so start from there. :)

On second thoughts, it could be the battery.. I'd suggest trying a good battery off a mates bike or something and if it starts then, but it could be a mixture of both. The irregular charging fried the battery, etc.

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

The voltages seem roughly comparable to mine, the idle voltage is over 14v on mine.

Retest with hi-beam as thats how it should be tested.

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

What bout the drop in voltage when revving, is that not odd??

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

not realy, its way over 13v and on 14v which is not bad

whats yr idle revs? a 100revs +/- can vary the voltage quite a bit.

Does your bike start off the battery?
How old is battery?

what was the sequence of events to get to the 12.01v?

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

Connections all good?Battery and earth straps,and the live one to the starter motor.

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

Idle is 14-1500rpms when warm

I've only had the bike a few weeks, to begin with it started off battery, was only this week it started playing up. Not sure of age of battery, think from memory the guy said it had been replaced fairly recently....

Connections to battery seem solid, not checked any others though....

Before going to 12.01v i put the ignition on, waited on fuel light going out then tried turning it over until it died....

Re: Diagnosis please - Battery vs Reg/Rec vs Other
 

I'd say the battery was suspect.