Connecting Earth

[Vince]

One of the early mods done to my bike by John Wilson was a really thick welding type cable he connected from the battery earth terminal  to the rear bolt of the starter motor.He deleted the woven strap from the battery to the frame.
Today I noticed this cable was bolted to the engine mount behind and above  the starter motor and was not to tight,bloody loose actually.Is there any advantage between these connections.frame or stater motor the better option.Brett found a shock bolt loose the other day so I am going to do a lap of the bolts to check for tightness.

 

[Gravelroad]

Hi Vince, best solution is to route a cable directly from battery earth to the starter motor bolt. First picture below shows how I did it in on my bike. 10sqmm welding cable, note the copper plated nut and washer.

I bent the cable lug by 90 degree, then soldered the cable to the lug. Added just enough solder so that only half the length of the lug got filled. This keeps the wires flexible at lug connection and helps to avoid vibration damage. Finally I put a bit of battery grease inside the gap between cable insulation and lug, and covered all with an inch length of heat shrinking tube.

Second picture shows the remains of the ground wiring on my bike. All ground currents are running in copper wire.  The big one is a 10 sqmm woven strap covered with an insulation hose, routed from battery earth to the R/H fixing bolt of the tool tray. All other ground wires of the bike are also connected to the same bolt (rear light, R/R, ignition box, mains relais, starter relais, 2.5 sqmm ground wire into the headlight shell).

I'm running a zero compromise strategy when rebuilding bike electrics, which usually includes re-design of the wiring scheme and top of the shelf equipment. Always paying off.

 

[Vince]

So your running both,one from the battery to the starter motor and the battery to the frame. Interesting, All the earth returns come directly back to my battery,non std wiring. I wounder why John didn't keep a big cable to the frame as well.

 

[Gravelroad]

Vince, the reason why I took a loop over the frame is that I'm a lazy guy . I just wanted to avoid to mess around with heaps of ground cables ending on my battery earth. The extra loop allowed for a cleaner cable routing and has a more convenient handling, in case one has to take the battery out or to put it back in. However, have to admit that I didn't touch the battery since it went in there 3yrs ago 8). It simply does not require to be recharged by an external charger. Seems those PC680 are pretty good stuff.

Regards,
Stefan

 

[2622]

Vince

In theory ( though it doesnt always follow theory ) you shouldnt need the extra ground point on a 180 ( 120 yes as the engine is rubber mounted.... however that said the key to good electric's is good continuity to earth. So if you the earth on the starter then when you hit the starter there is less chance of any resistance in your starter circuit.
Guess we forgot to recheck the starter bolts after we fitted the ignition... did we have it out, think we did to run the loom.

More important to make sure your shock bolts are tight, also now is a good time to run over all your bike to make sure everything is tight as you have done a few K's since the rebuild and now everything has probably settled in.

Since Red sorted your starter out you havent commented on having issues starting when cold yet even with your good earth strap before you were... so the earthing is only one link in the chain to good electric's

Check all your bolts whilst you are waiting for your primer to dry and you should be good to go.

I was just kind of getting used to the Orange cover on one side of your bike