Electrics Again

[Rich_MZ]

Hi all ,
Problem with the TS 125 again.
When I put the main lights on the engine cuts out.
I have had a look around the posts at similar problems but apart from putting in a new battery other peoples solutions are hard to find.
Anyway here's what I have done and found , replaced points and condenser , replaced battery with 6v 14Ah SLA , replaced reg with solid state one , replaced fuse box with 2x in line fuses , repolarized the dynamo.
Unfortunately when the bike ticks over and I switch on the headlight the battery voltage falls away from 6v to about 5v and the engine misses and cuts out , what I have noticed is that the battery is not charging at tickover ( amp meter inline ) but the charge light is off ??? . When I rev the bike it charges at +6 amps @ 7.5v .
The wiring all seems ok and I have checked the connections for the charging / ignition , I'm thinking now that maybe the brushes are at fault , has anyone else had a similar experience ?
Thanks in advance.
Rich
Devon
1986 TS125 Alpine

[den]

take the lamps out and try the test again ,(ie , whilst engine running try the light switch again ) if it still fails then its a current drain somewhere in the wiring , if it does not then the load must be taking all the lions share of power and reducing power to the coil.in essence , dynamo old and frail,lol. wouldnt expect the charge circuit to work on idle anyway,

[DAVID THOMPSON]

old and frail springs on the dynamo brushes and clean the commutator
that's the copper place where the brushes run
more spring pressure should = more voltage and current flow
these things do not put out very much power any way
think about a led replacement for tail lamp to save on drain
dave

[Rich_MZ]

Hi every one .
I have found the problem and hope that explaining it here may help someone else also.

The symptoms I had where that the engine would miss and cut out with the headlight on , this also happen occasionally with the indicators as well .

I changed the battery , reg , points condenser and the brushes all to no avail, so what I decided to do was work my way through the connections .
As the connectors are crimped I soldered these and cut off and replaced the grubby ones soldering these as well.When I say soldered I mean I soldered the connector to the cable not soldering the connector to the thing its plugged into.
Anyway the problem was within the headlight , there is a thickish red cable , this is from the battery . There are many black cables , these feed the 6v (after the switch) to the coil , horn and brake light as well as the indicators . Some of these black cables are bunched into one connector , after replacing the connector on these thing improved straight away .
Everything works now . The headlight is bright and you can use the indicators with the headlight on , and of course the engine does not cut out. Hope this helps

[DAVID THOMPSON]

i have been a fan of soldering the crimp connectors on for years and not crimping them in place...
if you have a wire problem the wire can be replaced
i carry a gas fueled soldering iron on trips so i can salvage the connectors and make field repairs
nothing like running out of spade lugs in the middle of no where

up the end of the handle bar in a plastic bag with a string and a cork
great place for solder spade lugs and even a 3 foot piece or two of number 12 wire
fixed so you can fish it out of course
dave