XJ550RJ ground/earth problem? Exhaust surface sparks on startup.

Hey guys,

I'm having a bit of a strange startup problem with my '82 XJ550RJ. It seems that whenever I start up my bike on the side stand, the exhaust is making contact with the centre stand and sparking at the point of contact. It still starts but seems very odd.

When I take the exhaust off or push down the centre stand so that the two points are no longer making contact the bike no longer starts. The engine doesn't turn over and the only sound that can be heard is the starter solenoid clicking.

Could this be a ground issue? I know of two grounds on the bike, there's one from the starter button to the forks and one from the battery negative to the frame.

Thanks!

Nathan

 

There should be a large ground cable to the engine as well. I suspect it is missing and the starter is getting its ground through the exhaust from the frame when they are in contact. I don't have that exact bike but I suspect someone will chime in soon that does and can explain where this cable should be and what it connects to.

 

Oh really? That's good to know. The previous owner moved the battery from the original position to under the back of the seat, so maybe it just needs wiring back up!

 

the battery ground goes down to the motor and there is a second wire built into the ground wire harness that goes to frame at the screw at bottom of battery box.
the frame needs a ground and motor needs a ground so the starter works

 

The fact that the battery was moved is a good sign that you need to check the wiring. Yes there needs to be a good heavy ground to the motor.

 

At the moment the battery is grounded to the frame via a 4 inch cable. Would you guys recommend removing this existing ground and adding a new ground from the battery neg to the motor, or just adding the new ground so that there are two grounds running from the battery neg?

I have some beefy 27amp copper cable, do you think this would be suitable?

 

beefy cable from battery to motor is needed.and one to the frame from battery or from motor to frame this is not a very large wire.

6 gauge wire is what you need from battery to motor


27 amp wire is too small for starter what voltage is listed with the 27 amp?

from chacals catalog

If the wire OD is 2.03mm - 2.19mm (.0799 to .0862"), then it's 20-gauge (20g) AWG or 0.40mm squared (metric size).
NOTE: 20g wire is rated for a maximum load of 11 amps of current at 12VDC.

If the wire OD is 2.26mm - 2.42mm (.0890 to .0953"), then it's 18-gauge (18g) AWG or 0.75mm squared (metric size).
NOTE: 18g wire is rated for a maximum load of 16 amps of current at 12VDC.

If the wire OD is 2.48mm - 2.64mm (.0976 to .1039"), then it's 16-gauge (16g) AWG or 1.25mm squared (metric size).
NOTE: 16g wire is rated for a maximum load of 22 amps of current at 12VDC.

If the wire OD is 2.89mm - 3.05mm (.1138 to .1201"), then it's 14-gauge (14g) AWG or 2.00mm squared (metric size).
NOTE: 14g wire is rated for a maximum load of 32 amps of current at 12VDC.
NOTE: 14g wire is the largest size wire normally found in the wiring harnesses on these bikes. Battery cables and the solenoid-to-starter motor cable are larger, of course, but of all the main harness and accessory wiring, 14-gauge is the largest that you'll find.

If the wire OD is 3.49mm - 3.65mm (.1374 to .1437"), then it's 12-gauge (12g) AWG or 3.00mm squared (metric size).
NOTE: 12g wire is rated for a maximum load of 41 amps of current at 12VDC.

If the wire OD is 4.32mm - 4.48mm (.1701 to .1764"), then it's 10-gauge (10g) AWG or 5.00mm squared (metric size).
NOTE: 10g wire is rated for a maximum load of 55 amps of current at 12VDC.

 

motor connector from chacal
HCP10092TP1418 Aftermarket brass closed RING TERMINAL, original crimp-on style connector (we recommend soldering as well as crimping for electrical integrity of the connection). Proper size for the hot solenoid stud, or for use with any of the engine case ground bolts. Terminal only, no insulation included. Each:


HCP11134BRK Aftermarket brass closed RING TERMINAL, original crimp-on style connector (we recommend soldering as well as crimping for electrical integrity of the connection). Proper size for the hot solenoid stud, or for use with any of the engine case ground bolts. Terminal with clear insulating sleeve included. Each:

 

Hey guys,
Thanks for all of your replies - just a quick update! I rewired another ground from the battery neg to an engine bolt and its fixed the problem! Thanks for all of your help with this.

 

is that motor rubber mounted? how is it not getting ground through any of the motor mount bolts?

 

bad ground wire or connection at motor could have been corroded would be my guess