Battery Ground

[bikelee]

I would like to do some preventive maintenance. Can anybody tell me where the battery grounds to the frame ? Also I want to put a strap from the rectifier to the frame. I assume i put it where the rectifier attaches with one of the two bolts and behind one of the front cover bolts ? Thanks for any help !

[docc]

b'lee,

The battery ground wire is bolted to the back of the gearbox above the drive shaft output. Good place to do a clean and lube while being sure the terminal stack on the battery is also clean and tight (most of the wiring harness earths back to the terminal stack).

 

Yes, ground the regulator from its case back to the timing chest. Again, be sure to clean the surfaces (including paint) and apply some weather protection (dielectric grease, Vaseline, KY jelly . . . what ever is, er, 'handy'   ).

 

Also consider adding a ground from the frame to the engine. I used the same timing chest bolt as the regulator ground and went to the bracket for the fuel filter on the right side of the frame above the valve cover on my Sport. I did this since I've grounded my horn relays and headlamps back to the frame.

[Kiwi_Roy]

Some bikes have the ground behind the seat release key, not a very good spot.

[sculler2x]

I ran a big fat wire from the battery to the bolt that holds the starter motor. I made sure the bolt and case were very clean. I used anti-seize compound to keep out moisture and prevent electro-corrosion. This made a huge improvement in starting the engine.  It is the same trick I, and many others, have used on their BMW twins.

[bikelee]

I ran a big fat wire from the battery to the bolt that holds the starter motor. I made sure the bolt and case were very clean. I used anti-seize compound to keep out moisture and prevent electro-corrosion. This made a huge improvement in starting the engine.  It is the same trick I, and many others, have used on their BMW twins.

I am assuming you ran the big fat wire from the negative terminal on the battery to the starter motor bolt ? Thanks !!

[sculler2x]

I ran a big fat wire from the battery to the bolt that holds the starter motor. I made sure the bolt and case were very clean. I used anti-seize compound to keep out moisture and prevent electro-corrosion. This made a huge improvement in starting the engine.  It is the same trick I, and many others, have used on their BMW twins.

I am assuming you ran the big fat wire from the negative terminal on the battery to the starter motor bolt ? Thanks !!

Yes, and I carried this one step further by running a 4 gage wire from the battery+ to the starter motor solenoid.  My next upgrade will be running an 8 gage wire from the regulator - to the bolt of the starter motor.  You can get marine wire and crimp on lugs at West Marine for example.  The wiring on our bikes is way undersized.

[Kiwi_Roy]

Make sure the start relay is not powered through the ignition switch,

The solenoid draws over 40 amps for a split second and the resistance through the switch restricts it too much.

My 2001 came standard with the solenoid powered straight from the battery through a fuse.

[docc]

Make sure the start relay is not powered through the ignition switch,

The solenoid draws over 40 amps for a split second and the resistance through the switch restricts it too much.

My 2001 came standard with the solenoid powered straight from the battery through a fuse.

Roy, How could those paths be verified?

[Kiwi_Roy]

Make sure the start relay is not powered through the ignition switch,

The solenoid draws over 40 amps for a split second and the resistance through the switch restricts it too much.

My 2001 came standard with the solenoid powered straight from the battery through a fuse.

Roy, How could those paths be verified?

Remove the start relay and measure for voltage in the relay base at the large top terminal (30) to the chassis

It should be there even with the key OFF.

If it only comes on with the key ON it's through the switch.

 

I'm not saying it won't work through the switch if the contacts are nice and clean, but it only takes a little resistance there and it's seriously compromised.

[mznyc]

Thanks Roy!

[sculler2x]

Here is how I ended up improving things.  I ran an 8 gage wire from the regulator + to a max fuse block.  I connected the battery + and the other + lines to the fuse block as seen in the next photo.  I ran an 8 gage wire from the case of the regulator to the starter motor bolt where the battery - also connects to the starter motor.  Notice that I put the battery line as close to the case as possible.  The bike starts on the second compression stroke and the rest of the electrical gremlins have gone away.  The other thing that helps a lot is putting contact grease on all connectors.  This prevents fretting corrosion as well as excluding moisture and oxidation.