Sudden loss of power

The wire for the tach wraps around the plug wire not the coil sorry.

I'd hope the valves would be ok I just did them less then 600 km ago. However I did do and entire top end head rebuild and bore so some settling could have occurred. I understand poor valve clearance would cause power issues but how would it cause total power failure?

if valve clearance is too tight, the valve will stay open a bit when it gets hot(expansion), thus loosing compresion, and power.

Thank you OMR for your info through Pm. I have found a possible cause.

First I measured the plug wire, coils, and primary wires.
grey Dyna 8mm suppression wire
1-5.2 ohms
4-4.8 ohms
Primary wire 0.4 ohms - 3 exposed breaks in the wire jacket!!! kinked and aged miss this last year when I did my electrical inspection or recent. - Repaired reads 0.4 ohms
1/4 coil readings
Primary -3 ohm
Secondary - 0 looks like it is dead

grey Dyna 8mm suppression wire
2-4.5 ohms
3-4.8 ohms
Primary wire 0.7 ohms
2/3 coil readings
Primary - 3.5 ohms
Secondary - 13.7K ohms

Looks like a short and bad coil is the issue. Why would this only show up when warm? I was getting spark from all the plugs???

I should add I have the Wired George relay mod as well. The Dyna S is running off the yellow/red wire relay #86 from the kill switch vs the #87 relay powering the coils. Don't know why I did this but power is power so it shouldnt matter right? It worked ha!

Something to note I believe all these years I have had my Dyna S hooked up backwards and WRONG!! I found OMR's Dyna write up and I had my 1/4 black primary wire connected to the Dyna 2/3 black wire! FING dyna manual! How is this even possible I have been riding this bike like this for a few years?

I did some more checking tonight and found a few oddities

1. Both coils produce a solid spark?
2. Coil 1/4 the bad one has visual cracks along the mounting bracket and cracks around the primary contact!! possibly from a short in the wire I found. That may explain why when it warms up I lose power.

My spark plug tips appear different as well
1-Brown/yellow deposits
4-Brown with black tip
2-black with grey tips
3-black with grey tips

Thirdly, is it possible my Dyna S was made backwards? (Friday special heh) As I mentioned in the last post I had thought I had the lead backwards as I marked them when I took it apart. This may not be the case. I tested it by connecting the leads up as written in OMRs post. White with black heat shrink goes to 1-4, black with green heat shrink goes to 2-3. Well using a test light my F mark reads 2-3 on my 1-4 coil....... reverse them and it works fine and how I was using it...

Perhaps rotor installed 180° off.

Good Fortune!

.

Patton wrote: Perhaps rotor installed 180° off.

Good Fortune!

Well that would be logical but according to the diagram the plate is mounted with the 1/4 in the back and 2/3 forward. As the white lead comes off the 1/4 and that lead is mounted on the plate to the rear it should be setup correct.

Funny thing is I just switched the the leads and it works fine ha.

Now I just have to wait for new coils and test this all again.

So I get the newbie award this time YES the rotor was installed 180 off haha thanks Patton please pass me the stupid sign.

Coils are here hope to have it all together tonight. Weather is getting better and the vintage bike show is this weekend so I'm hoping to ride it there!

Oh ya the beast is alive. Fired up and ran strong.

.... Ran strong must be an understatement for she must have all kinds of power compared to how she was configured... :laugh: Excellent!