Ignition module issues

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gspd
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Re: Ignition module issues

Post by gspd »

When you say 'bike running', do you mean properly running?
Have you checked your ignition timing? Is that situation resolved?
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"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
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kojones
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Re: Ignition module issues

Post by kojones »

Haven’t checked the timing, if the alternator isn’t functioning properly it can cause all kinds of weird stuff, including blowing up the ICU with too much voltage or false ignition with ac ripple.

So finding the cause why it doesn’t charge should be the first thing to do, right?

Removed the diode board and checked them with a multimeter, all 6 large and 3 smaller measure fine.
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gspd
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Re: Ignition module issues

Post by gspd »

please re-read my last post. I don't think you understood what I'm saying...
In the very least, disconnect the damned alternator and see if you can get the engine timed correctly!
Stop jumping ahead of yourself.
Right now, it's feels almost as if you are trying to fix a leaking radiator on a car that has a blown engine.
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
kojones
Posts: 40
Joined: Tue Jul 31, 2018 6:13 am

Re: Ignition module issues

Post by kojones »

gspd wrote: Wed Aug 01, 2018 8:37 am Should be symmetrical, I have one apart in front of me right now

Question 2: Can you easily move the hall trigger rotor a few (13?) degrees CW by hand and does it spring back when you let go?
You'll have 2 remove the beancan cover and its front shaft support plate to check this.
Sounds like your advance mechanism is jammed on full retard OR your new springs are way too strong.
OK I checked this and the advance mechanism works fine.
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gspd
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Re: Ignition module issues

Post by gspd »

The bean can has an input shaft (camshaft side) and a rotor (trigger) shaft.
These are 2 separate parts.
It is not a one piece shaft right through the beancan.
https://beta.photobucket.com/u/1990gspd ... b5bed5caf3
There is a cam system between the input and output shafts which allows a movement of 13 degrees ( thus 26 degrees advance at the crankshaft).
This movement is controlled by weights being forced apart by centrifugal force as the engine gains rpm.
At idle the springs pull it back to full retard (S mark) and as the engine accelerates it will advance to the F mark (or Z mark on newer bikes, same thing)

If you immobilize the camshaft end (as if it was installed on the engine) the front part of the shaft (trigger rotor) should rotate freely (by hand) 13 degrees and then spring back when released.

I have a feeling yours is jammed on full retard, which would explain your problem.
Maybe the guy who fixed you dash also fixed your beancan?
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
kojones
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Joined: Tue Jul 31, 2018 6:13 am

Re: Ignition module issues

Post by kojones »

It works fine. Even if it was jammed on full retard I should be able to get the timing adjusted on idle, correct?
kojones
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Re: Ignition module issues

Post by kojones »

I think I’ll have to get the valve covers off and check if valve clearances are largest just at the OT mark or a few degrees off, that should tell if I have the timing chain one tooth off or not.
kojones
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Re: Ignition module issues

Post by kojones »

With the three stator wires connected to the alternator it refuses to rev and dies, but when I disconnect them it revs without any problems. Charge light lit all time and can’t get the timing advanced enough, alternator connected or not.

So I have two problems, one with the timing and second with the alternator. Still not sure if the ign. timing can be retarded by the ICU, as it was perfectly timed before the ICU blew. The "new" ICU is a VW/Audi part 191905351C.
Last edited by kojones on Thu Aug 02, 2018 3:23 pm, edited 1 time in total.
kojones
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Re: Ignition module issues

Post by kojones »

I took the stator off, winding has a few ohms resistance to ground and it should be isolated. Can't find any bad spots in insulation so it's probably time to get a new one :(

Time to fix the timing issue when I wait for that.

Damn that's expensive part. Any VW equivalents?
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gspd
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Response to some of your latest questions

Post by gspd »

1 - I took the stator off, winding has a few ohms resistance to ground and it should be isolated. Can't find any bad spots in insulation so it's probably time to get a new one :(
NO it's not! No point on me explaining why at this moment.

Time to fix the timing issue when I wait for that.
RIGHT ON BRO! Smartest thing you've said so far!!!

Damn that's expensive part. Any VW equivalents?
NO, but yours is probably good.

2 - So I have two problems, one with the timing and second with the alternator. Still not sure if the ign. timing can be retarded by the ICU, as it was perfectly timed before the ICU blew.
I don't believe that the ICU retards or advances the timing, but I'm not 1000% sure on this one, only 99.9%.
Possibly it establishes a starting reference point for the advance curve and the one you have now sets it too far retarded, but this is just a guess.
Wait till your other ICU arrives and see if that fixes it. Forget about your charging system for now, leave it disconnected for now and get the timing issue resolved first.

3 - I think I’ll have to get the valve covers off and check if valve clearances are largest just at the OT mark or a few degrees off, that should tell if I have the timing chain one tooth off or not.
THAT WON"T WORK the valve clearances remain fairly constant for many degrees of camshaft rotation.

THE ONLY WAY
to know if the cam and crank are properly aligned is to remove the timing chain cover and visually check that the marks on the cam and crank sprockets are aligned. I wouldn't do this right away, it may not be necessary.

4- It works fine. Even if it was jammed on full retard I should be able to get the timing adjusted on idle, correct?
Not necessarily, it could be jammed beyond full retard if something was butchered or modified in the advance mechanism.

To summarize:
As I stated before, the smartest, easiest, and possibly only way to diagnose the timing problem is to electrically and electronically ISOLATE THE ENGINE AND ITS IGNITION SYSTEM AND ITS STARTING SYSTEM FROM THE WHOLE REST OF THE BIKE INCLUDING ITS MAIN WIRING HARNESS (INCLUDING ALL THAT BUTCHERED CRAP IN THE DASH).
sorry if I'm yelling
:oops:
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
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