Troubleshooting Bad Starter (?)

[Fred W]

Current measured at the negative battery lead will be higher than the starter current due to it including all of the current that powers the rest of the bike, but you can just turn the bike on and measure the rest of bike current first and subtract that amount from what you measure while cranking to determine the actual starter draw.

 

[mcatrophy]

Current measured at the negative battery lead will be higher than the starter current due to it including all of the current that powers the rest of the bike, but you can just turn the bike on and measure the rest of bike current first and subtract that amount from what you measure while cranking to determine the actual starter draw.

Less than 4 amps, I would suggest inconsequential compared with starter current that is going to be at least 30 amps, and if ailing, considerably more, and such a relatively easy access for a first check.

 

[wfooshee]

30 amps would be on the bench, unloaded. Cranking the bike, expect to see >60.

 

[YummYam]

Hi . Have done the current draw test with a Fluke 375 borrowed from work, think I did it right. Battery had been on tender all night, then off it for couple of hours, read 13.1 volts. Put the meter on the positive lead and video'd the results so as not to get confused (easy for me).

As I pressed the start button, starter was sluggish, reading went to 97amps then shot up to 233! as the motor spun over, before dropping back as she fired up.

Next, put meter on negative lead, hit button, meter went to 78amps then briefly to 161 as motor started.

Not sure if the next test makes sense, but used my own DVM connected to the battery negative post and the starter side of the starter relay. Hit button, meter went to 176 mV, then 18.09 VOLTS, then down to 10.6 volts. Then as she fired up, down to really low mV.

Not sure what all this means, except going by what I've read so far, my starter motor is quite likely................. toast.

Please do chime in with any comment/suggestions.

Thanks, Steve

 

[dcarver]

If you're going to replace it..

 

[dcarver]

https://vimeo.com/182802622

 

[YummYam]

Appreciate the help and advice, pics sure do help to see what's involved.Now just got to get head around doing the job, and laying out the wonga!

Just did the same test with the clamp on meter on the battery positive wire, this time shorted across the relay terminals with a screwdriver as suggested elsewhere. Starter spun ok but pulling 120+ amps.

Its a goner for sure. F@*k.