Troubleshoot help. No Spark R90/6

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Kurt in S.A.
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Re: Troubleshoot help. No Spark R90/6

Post by Kurt in S.A. » Sat Jun 17, 2017 3:47 pm

jjwithers wrote:
Sat Jun 17, 2017 9:56 am
The fact that you say that makes me think it is one of the two items I did not replace, the booster and the electronic ignition.
If it is not fuel related, I have a feeling it is one of them...
Since you can't ride the bike without an ignition system, your only choices are to 1) remove the booster or 2) replace with another ignition system, electronic or points.

Kurt in S.A.

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jjwithers
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Re: Troubleshoot help. No Spark R90/6

Post by jjwithers » Sat Jun 17, 2017 7:12 pm

I figured it out. Yes, it was a bad ground that had me getting an iffy spark, but then I still had similar symptoms.
It turned out to be bad fuel filters. I saw them filling with gas but no gas was getting to the carbs. Douph. $10 fix and it runs great now.
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Kurt in S.A.
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Re: Troubleshoot help. No Spark R90/6

Post by Kurt in S.A. » Sat Jun 17, 2017 8:05 pm

That's very different. Never mind!

Emily Litella

Rob
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Re: Troubleshoot help. No Spark R90/6

Post by Rob » Sun Jun 18, 2017 12:20 am

I never used those filters, and this (besides the waste of money) is why.
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Zombie Master
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Re: Troubleshoot help. No Spark R90/6

Post by Zombie Master » Sun Jun 18, 2017 1:19 am

Grounds first!
Any and all disclaimers may apply

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jjwithers
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Re: Troubleshoot help. No Spark R90/6

Post by jjwithers » Sun Jun 18, 2017 6:41 pm

These were the large paper style filter. I never use them either. I know the Petcocks do not have the screens on them so I put the small style fuel filter instead.
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Re: Troubleshoot help. No Spark R90/6

Post by Rob » Sun Jun 18, 2017 11:33 pm

No screens?!?

Blasphemy!

His airhead should be taken from him, and brought to my house, where, if nothing else, I will empty the fuel tank every winter and dry it out.

That allowed me to visually check the large screens once a year, and clean out any crap that got below the petcock.
Rob V

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jjwithers
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Re: Troubleshoot help. No Spark R90/6

Post by jjwithers » Mon Jun 19, 2017 11:16 am

Humm... the bike owner contacted me and is having issues again. SO it seems that I found many small gremlins but there may be something larger still looming about. He is referring to a backfire/rough running issue. So, the backfire could mean timing, or rough running could mean carbs.
www.beemersandbits.com
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
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Re: Troubleshoot help. No Spark R90/6

Post by Airbear » Tue Jun 20, 2017 3:03 am

JJ, I'm as confused as Kurt in S.A. about the electronic ignition plus booster thing. Can you please clarify? Like Kurt, I have the Dyna III ignition, just like this:

Image

Is this is what is in the bike or something different? If so I would be checking the mounting of the sender plate, the pickups on the plate and the rotating magnet's attachment to the camshaft. Also make sure the ATU weights are lubed and free to move.

If the bike shows no spark immediately after stopping but it returns when cool I would be suspecting the electronics in the box.

Ah, I've just done some googling and apparently folks will sometimes add a Dyna Booster to bikes with electronic beancan ignitions, so maybe this situation is not so weird. Anyway, I'm still keen to know what is under the front cover and what it is connected to.
Charlie
and Brunhilde - 1974 R90/6
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jjwithers
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Re: Troubleshoot help. No Spark R90/6

Post by jjwithers » Tue Jun 20, 2017 10:33 am

I am referring to that box in your photo as the 'booster'.
Perhaps I am incorrect in my terminology.

FWIW - I have a bean can ignition with points and use that box and I have not had to touch my points/timing in 5 years (4k miles). It is an occasional sunday rider kind of bike.
www.beemersandbits.com
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
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