Author Topic: Could this of been the cause after all this time?  (Read 816 times)

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Offline fodzilla

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Could this of been the cause after all this time?
« on: November 04, 2015, 09:29:39 AM »
Hi guys,

I was reading over some old posts online and came across something that might of been a cause of my problems.  Problem is though, I've never heard about it before.  (My first build, so limited experience sorry)

Could a broken charging systems such as what I had, been the cause of fouled plugs after only a few of miles riding? (Black dry carbon reading)

I've only ever got a few miles on my bike before the battery died and I pushed it home with the plugs ending up fouled.(Black dry carbon reading, clean them off and they are fine again with fully charged battery)

I've recently read that you can foul plugs like this by having a "weak spark" caused by poor/broken charging system. 

BTW - My charging system is fixed and kicking out 14.5 volts as it should now.  I hadn't earthed the damn field coil due to a broken connector block connection.

History of my problems this summer to put in context...

1. Made my own wiring loom but couldn't get the charging system working.
2. Replaced plugs as I was having starter issues, bike would ride but battery would die quickly as expected
3. Fixed charging system but couldn't get the damn thing to start on last attempted ride. (still haven't been out on it with a working charging system)
4. Pulled the plugs as I thought the carbs might be rich and found them to be black dry carbon looking after only a few miles riding a few weeks ago

I've now read that this could have been related to carbon build up from "Weak Spark"

I fear I've been chasing down a problem all from a simple issue with the charging system.  Or do I continue to tear my carbs apart and test different jets.
CB500 Four K1 '75

Offline calj737

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Re: Could this of been the cause after all this time?
« Reply #1 on: November 04, 2015, 10:01:17 AM »
Weak spark usually manifests itself as wet plugs, not dry. The lack of spark retards the combustion, thereby fuel is unburnt. Dry, carbon-fouled plugs is usually too much fuel, not enough air, etc.

Sorry. Now go clean your carbs  ;)
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Offline flybox1

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Re: Could this of been the cause after all this time?
« Reply #2 on: November 04, 2015, 10:34:41 AM »
Sorry. Now go clean your carbs  ;)
agreed!

no need to 'test' jets. 
tell us about your intake and exhaust setup, and what your carbs are currently set at(main, pilot, mixture, float height...etc)

or at least link us to the thread where the other info is located.
if jetting is correct for your intake and exh, but you're fouling plugs, verify your float height, and go 1/2 turn LEANER with your mixture screw..for starters.
« Last Edit: November 04, 2015, 10:37:13 AM by flybox1 »
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