scott s
XS650 Guru
A few months ago I picked up a crusty, survivor 1980 SR500. Got it for a great price. The chrome was shot, so I sourced new shiny bits, rebuilt a set of XS650 forks with the adjustable pre-load, got some nice shocks, upgraded the brakes, etc. Picked up a pumper carb and cool vintage exhaust.
I'm well on my way to having a cool Thumper.
Before:
I'll post up an "after" when I'm done. But I'm banging my head against the wall trying to get spark on this thing.
First thing I did was trim back the wire on the coil and install a new cap and plug. When that didn't work, I ordered a new coil from Rex's Speedshop.
This one: https://www.rexs-speedshop.com/product/htc10-sr-xt-tt-400-500-600-ignition-coil/
When that didn't work, I tried a new CDI unit.
This one: https://www.rexs-speedshop.com/product/sr400-sr500-cdi-unit-1979-97/
When that didn't work, I did these tests here: https://www.rexs-speedshop.com/wp-content/uploads/2018/10/Yamaha-SR400500-Ignition-Testing.pdf
I can find no fault with the wiring harness or controls. I checked all connections. I checked the harness from end to end and with each component/section. Checked grounds.
Gave up and sent it to my buddy's shop. With his better meter, he diagnosed a bad stator. Sent the stator to Rick's for a rewind and it still has no spark.
Confirmed stator, rotor and flywheel match. Confirmed flywheel/rotor hasn't slipped on crank.
We confirmed that I ordered the correct CDI from Rex's (I did). We asked Rex's to test both the old and new CDI units but they declined, saying that taxes, import duties and fees make it not feasible.
-New correct coil from Rex's (includes cap)
-New plug
-New CDI
-Stator rewound
-Harness and controls checked
-Confirmed stator/rotor/flywheel match
-Confirmed rotor has't spun on the crankshaft
-Checked, tested and cleaned multiple grounds
Now what?
I'm well on my way to having a cool Thumper.
Before:
I'll post up an "after" when I'm done. But I'm banging my head against the wall trying to get spark on this thing.
First thing I did was trim back the wire on the coil and install a new cap and plug. When that didn't work, I ordered a new coil from Rex's Speedshop.
This one: https://www.rexs-speedshop.com/product/htc10-sr-xt-tt-400-500-600-ignition-coil/
When that didn't work, I tried a new CDI unit.
This one: https://www.rexs-speedshop.com/product/sr400-sr500-cdi-unit-1979-97/
When that didn't work, I did these tests here: https://www.rexs-speedshop.com/wp-content/uploads/2018/10/Yamaha-SR400500-Ignition-Testing.pdf
I can find no fault with the wiring harness or controls. I checked all connections. I checked the harness from end to end and with each component/section. Checked grounds.
Gave up and sent it to my buddy's shop. With his better meter, he diagnosed a bad stator. Sent the stator to Rick's for a rewind and it still has no spark.
Confirmed stator, rotor and flywheel match. Confirmed flywheel/rotor hasn't slipped on crank.
We confirmed that I ordered the correct CDI from Rex's (I did). We asked Rex's to test both the old and new CDI units but they declined, saying that taxes, import duties and fees make it not feasible.
-New correct coil from Rex's (includes cap)
-New plug
-New CDI
-Stator rewound
-Harness and controls checked
-Confirmed stator/rotor/flywheel match
-Confirmed rotor has't spun on the crankshaft
-Checked, tested and cleaned multiple grounds
Now what?