Grounding Engine

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Spub
Mach 3
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Grounding Engine

Post by Spub » Thu Mar 29, 2007 8:59 pm

I recently had trouble with my kick start Norton not starting up, and I eventually traced the problem to the connections in the ignition wiring. Once cleaned up the bike ran fine, but since it was just wired in August when it was restored, I figured the ground may be a bit marginal. I therefore ran a ground wire directly from the negative terminal to a bolt on the rear of the block, and bike continues to start right up. I then figured, why not do the same on the 900. Even though the bike has been starting fine, I figured why not....so I ran an ground wire from the negative terminal to the clutch adjustement bolt, as insurnace. I figure with a kickstarter, weak spark is something that must be guarded against at all costs....
1982 Laverda 180 JOTA, 1975 Moto Morini 3 1/2 Sport, 1993 Moto Guzzi Daytona, 2010 KTM Adventure 990, 1974 Laverda SFC #17188

Den
Mach 3
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Joined: Fri Apr 09, 2004 6:02 pm
Location: Florida, USA

Post by Den » Sat May 19, 2007 7:40 pm

I hope you mean the clutch *cable* adjustment bolt.

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BevHevSteve
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Post by BevHevSteve » Sat May 19, 2007 9:26 pm

yeah that is what he meant, that is what I told him to do and recommend to everyone........ Just run a good wire from the neg terminal to the clutch adjustment nut where it seats against the engine block. Do this ALONG WITH the normal negative terminal ground strap or wire....
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Paul Croft
Cucciolo - the Lil Pup
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Re: Grounding Engine

Post by Paul Croft » Tue Aug 29, 2017 12:39 pm

Hi Steve, could that account for having a weak spark on the rear cylinder. (rear cylinder cooler) I have checked the resistances all through, including coils, pick ups, resistors, all reading fine. The bike is intermittently popping and banging, makes no difference with the lights on, but hates full throttle. I will put a healthy earth lead on tomorrow, and see how it goes. Sorry, I'm just thinking out loud. If it works I will let you know!

wdietz186
Cagiva Alazzura
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Re: Grounding Engine

Post by wdietz186 » Wed Aug 30, 2017 9:09 am

Paul, when checking the pickup resistances you also need to check to see if either of the wires on each pickup are shorting to ground. In addition, you need to check if the wires on one pickup are shorting to the other pickup wire[s]. Check one wire from one pickup to one wire of the other pickup,do it for all four wires. You should have infinite resistance [no contact] between them. What happens is the insulation breaks down on the pickup wires and they will short together or short to ground or all of the above. You will get weak spark, no spark, or the spark at the wrong time depending on the level of the vibes moving things around. Many times the contact is occurring inside the gland nut where the leads come through the primary cover. Steve stocks the wire and stuff to replace the leads, it's not rocket science but it can be a bit of a pain to do. You do need to be mindful of the polarity of the pickup wires or your timing will be awonky when you go to run it.

Paul Croft
Cucciolo - the Lil Pup
Posts: 14
Joined: Thu Dec 15, 2016 2:25 pm

Re: Grounding Engine

Post by Paul Croft » Fri Sep 01, 2017 11:32 pm

Ok thanks for that wdietz, I will try that later as earthing the engine made no difference. The spark on the rear cylinder does appear to be weaker.

Paul Croft
Cucciolo - the Lil Pup
Posts: 14
Joined: Thu Dec 15, 2016 2:25 pm

Re: Grounding Engine

Post by Paul Croft » Mon Sep 04, 2017 2:36 am

Wdietz, It worked, the insulation going into the engine case was cracked, under the external insulation!
It's a year since the passing of my brother, (who's Darmah I have just restored) and at the weekend we got together where we used to camp, family and old friends for a 'Dave Fest'. I'm sure you will understand how much it meant to turn up on his old bike, to stand it along side the others, and enjoy a beer or three?, whilst remembering old times. Thank you. Paul.

wdietz186
Cagiva Alazzura
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Re: Grounding Engine

Post by wdietz186 » Thu Sep 07, 2017 8:55 am

Glad it worked out for you Paul. Remember, most carb issues are electrical and vice versa.

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