I may be losing hair but volts LOL

[wymondham1979]

Hi Guys a couple of questions for the knowledgeable ones
Question 1
After reading several posts I bought a tims analogue volte gauge and wired directly to the battery (bike not running) it shows a little over 12 volts and goes up to around 14 volts with the bike running, I figured all good and the suggested placement on the forum is after the switch in the headlight but none of the headlamp wires show a full 12 volts some around 9 volts ? where has the other 3 volts gone ? I may be losing hair but volts LOL can anyone enlighten me ,can I just connect it directly to the battery ? Do voltmeters drain the battery?

Question 2
My cam chain tensioner didn't have the copper damper washer on another thread it says its 15mm x 2mm (6.5mm hole )is it an essential part ? Other post suggest they didn't all have them?

Had a couple of sunny days here in the uk and am loving the bike
Many thanks

 

[retiredgentleman]

Hi Guys a couple of questions for the knowledgeable ones
Question 1
After reading several posts I bought a tims analogue volte gauge and wired directly to the battery (bike not running) it shows a little over 12 volts and goes up to around 14 volts with the bike running, I figured all good and the suggested placement on the forum is after the switch in the headlight but none of the headlamp wires show a full 12 volts some around 9 volts ? where has the other 3 volts gone ? I may be losing hair but volts LOL can anyone enlighten me ,can I just connect it directly to the battery ? Do voltmeters drain the battery?

Question 2
My cam chain tensioner didn’t have the copper damper washer on another thread it says its 15mm x 2mm (6.5mm hole )is it an essential part ? Other post suggest they didn’t all have them?

Had a couple of sunny days here in the uk and am loving the bike
Many thanks

If you saw 14 volts, then your charging system is working well for you.

Lets say your bike is idling (1200 rpm); its normal to have about 13.5 volts. The various loads on the bike should all be within a volt of that i.e. 12.5 volts. If you are seeing 9 volts, then the connectors/wires leading to that particular load are corroded/oxidized badly. Take apart the offending connectors/sockets etc. and clean them so they are bright and shiny. The missing 3 volts is called voltage drop and the the 3 volts is producing heat at the connector(s)/sockets/wires. Amount of heat is E squared/R or 9 divided by the resistance of the connector.

Direct to the battery.................no that's not the best place. Voltmeters draw a very tiny amount of current, but why would you want any constant drain on the battery, if its not necessary. You can connect the voltmeter any place you want that is down stream of the ignition switch. I have my voltmeter connected to the brown "signals" wire inside my headlight bucket.

The early years 70 to 73 may not have had a damper, but I think all the later years 74 to 83 did. If your bike is a 79 then yes it should have the damper. The engine is noisy without the damper.

 

[wymondham1979]

Hi retiredgentleman many thanks for the info I made a copper washer as they don't seem available to buy and the bobbing in and out travel seems to have been reduced a little I have set it to flush with the end I think its quieter but its a xs so with all the other peripheral noise it's hard to tell LOL

As to the voltage drop I cleaned up a few connectors with some improvement only a couple are below 10volts is there an acceptable drop? is it just old worn out wiring ? I have a very limited knowledge of wiring is the old wiring likely to fail being oxidized ? I'm thinking maybe about rewiring the bike over the winter it's not something I really comfortable with but there are a lot of posts on rewiring and as the bike is my sort of retirement project I want to learn everything about it I can. I thought to leave the harness on the bike and duplicate alongside is that the best way to approch it ?

Another sunny say in the uk off for a spin before the 10 months of winter close in LOL

many thanks