Charging fault?

Hi Folks

Can i just get some thoughts on whether my opinion is correct?

I have been having ongoing electrical problems (99 model) where i need to plug in the optimate pretty much every second day when I am at work to ensure that it starts every morning.

recharged the battery last night and it seems to hold a voltage of 12.7..that seems fine to me.

did a leak test and no leaks detected.

checked regulated output and at idle it is just over 13v, however, when i raise revs to 5k the voltage drops down to below 12.7 (this is with lights on). this should be going up to between 13.5 and 15.5 yes?

checked unregulated output and it seems ok, roundabouts 70-80v across all three wires at 5k revs.

I am thinking the problem here is the reg/rec and will buy another (current one was a second hand replacement about 18 months ago as original exploded).

Am I right or should there be some more checks done before getting a new or second hand reg/rec?

thanks for your time.

sounds very much like reg/rec to me.

12.7 volts is very very low. Reg / rec goosed.

How many times has your battery gone flat? You maaaay have a bit of an unwell battery now if its been discharged lots, but see how you go with it

i would say battery as well tbh but im not expert if you have a spare battery i recommend testing the bike with a different battery and see what the voltages are then.

Originally Posted by Alpinestarhero

12.7 volts is very very low. Reg / rec goosed.

How many times has your battery gone flat? You maaaay have a bit of an unwell battery now if its been discharged lots, but see how you go with it

it has been flat numerous times now and is pretty old. i'll get a new reg/rec fitted and see what happens.


unfortunately i don't have a spare battery about but fingers crossed it is just the reg rec.

thanks for your thoughts folks.

[Spanner Man]

Good morning all.


One thing often overlooked when checking charging faults is the starter solenoid.
The output from the rec/reg has to run through the solenoid in order to reach the battery. So a defective connection (usually) inside the solenoid can give you the symptoms you describe.
If you're careful you can check this by running wires directly from the rec/reg output plug to the battery using male spade connectors & some wire of a suitable size. Obviously run the red wire to the positive terminal, & the black to the negative terminal. If your charge rate rises to more like the normal figures then the solenoid is a likely suspect. However, a defective connection in the wiring loom would also give you the same symptoms.

It wouldn't be an ideal situation to leave the wires in place, but if you can obtain the type of spade connector that fits into the terminal blocks you can first remove the original red wire from inside the terminal block, & run a new red wire to the lead on the battery side of the solenoid. If you do this, make sure you thoroughly tape up the removed terminal, for it will still be live.


Cheers.

also check the connections on the reg/rec may just need cleaning

Originally Posted by Spanner Man

It wouldn't be an ideal situation to leave the wires in place.

Why not?

Originally Posted by emcf

it has been flat numerous times now and is pretty old. i'll get a new reg/rec fitted and see what happens.


unfortunately i don't have a spare battery about but fingers crossed it is just the reg rec.

thanks for your thoughts folks.

Some garages can test the efficiency of your battery - it might give out a good voltage, but its ability to supply charge might be substantially diminished if its real poop On a cold morning, it might just decide it dosnt want to give you the cold cranking current you need

A good quality replacment battery (if you do need one, you might not) is a wise investment...many people have discovered cheapy ones do the job fine...but not for long!

guys

thanks for all the advice. just to give this thread a conclusion I bought a replacement reg/rec (about 65 quid inc p&p) before reading spannerman's comments.

fitted it today (after having to buy new bolts...new version doesn't fit with the old bolts grrr!) and at 5k revs it is putting out 14 odd volts so, to me, that seems healthy.

hopefully that will be the problem solved but if it continues i'll try spannerman's suggestion and look into getting a new (decent quality!) battery as per alpinehero's suggestion.

thanks again for your time folks.