SFC wiring diagram US spec

motoddrob

motoddrob

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S/W Australia
Does one exist?
I sort of was under the impression it used a modified SF2 harness having the same running gear, ND switches and Instruments, indicators.
Doesn't seem so
 
It’s fairly similar, which is a good reason to make something a lot more simple. The diagram for the non US version is simple and good.

Marnix
 
I'd be tempted to do a re-wire. would make it a lot simpler.
I did the Motodd so it's not a big challenge.
But for now I'll figure out this one. Don't have a battery yet but using a multi meter I'm slowly piecing it together.
 
Wow Phil, never seen that scheme before. Would also love a good scan.
The scheme illustrates the wiring well, because most connections were put behind the rubber cover of the headlight unit, which doesn’t offer much room for a tidy arrangement. The European version also has the connection strips in the same spot, but with much less connections/wires.

Marnix
 
Sorted this mess out today.
Cut and resoldered the dodgy ends that fix to the connector blocks.
Bigs thanks to Arancia for the wiring diagram. Big help in understanding the wiring.
Fitted a battery, turned the key and i had power.
I reckon I'll be pressing the starter button soon
 

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motoddrob said:
Sorted this mess out today.
Cut and resoldered the dodgy ends that fix to the connector blocks.
Bigs thanks to Arancia for the wiring diagram. Big help in understanding the wiring.
Fitted a battery, turned the key and i had power.
I reckon I'll be pressing the starter button soon
Click to expand...
Is that a good idea? Doesn't it make them brittle and more prone to breaking, and the solder to screw giving a poor connection over time? John IIS can elaborate?
 
motoddrob said:
Just keeping it original Lee
The ones I resoldered have lasted 50 years
Click to expand...
I’ve always done it that way too, only soldering the tips where the screw finds its grip. The screw connectors need some re-tightening after a while, that’s all.
The non US market (1974-1976) SFCs had a lot less wires behind the headlight cap, which makes things a bit easier.

Marnix
 
Soldering is good but will reduce flex which can lead to fatigue. I usually use solder but make sure the wiring is loomed and tied so the joint doesn’t flex.
Bootlace ferrules are the modern equivalent to tinning. Either way, it’s all about keeping the copper strands together and protected from damage by the screw.
 
Andy said:
Soldering is good but will reduce flex which can lead to fatigue. I usually use solder but make sure the wiring is loomed and tied so the joint doesn’t flex.
Bootlace ferrules are the modern equivalent to tinning. Either way, it’s all about keeping the copper strands together and protected from damage by the screw.
Click to expand...
Bootlace ferrules are an awesome bit of kit, but only for a few do ups and undo, do ups. When I worked on Italian packaging machines, a few various sizes were always kept on hand.

Too many squashes with the screws (when the screw was retightened on a virgin spot) saw them crack down the length which made a hot joint (according to the grappa induced wisdom of the Italian technicians). Perfect for this application though.
 
As I've said many times for the SF and SFC's or for any Breganzie for that matter without a Depressed Clutch Lever Starter Safety "DO NOT ground the Starter Solenoid to the frame. Ground the starter relay through the Neutral Switch in the bottom of the transmission." You CAN NOT trust the Starter Clutch Pac on the crank NOT to engage if you accidentally hit the Starter Button at Hi-Revs. If the Starter Clutch Pac on the crank Locks Up your starter internals will be nothing but ash - Been there Done That - Cost me $900 to have a starter shipped from the Breganzie Factory back in 74. I paid $1,600 for my 70 SF0 in 73 when then the EU Dealers went under in Canada. That's more then 1/2 what I paid for the bike and only road her for 45 years then sold her for $8,500 when I was 70, I'm 77 now and do not ride any more - That Motorcycle does not owe a dime except for the Shear Joy of being responsible for her. Do not think she was Not FAST - She could do 120mph down any stretch if you kept the momentum up and out cornered all of the Big 1000cc's for many years beyond her time ;o)
That 70 Breganzie 750 SF was faster then my 86 1100 Suzuki Geexer over the MOST tried road Race Course in Northern Ontario named the "Moose Mountain Mine Road" which also had the famous Jack Pine "1/4 Mile Stretch" were 1000's of racers from Northern Ontario, Montreal, Ottawa to Winnipeg, even some the States gathered to met on summer weekends to do their thing back in the 60's and early 70's - Expect at least 2000 participants every weekend who camped in the Gavel Pits along that Jack pin Stretch of the CLOSED OFF Moose Mountain Extended 69 HWY into the oblivion of the Cambrian Shield. That was my Back Yard when I was a teenager - Fast Muscle Cars and Motorcycles - Cops that actually would race you with their cruisers and Mayors of towns joined the masses cheering for their local hero's driving screaming 327's, 340's 396's 454's and 426 Hemi's against RD 400's, 1000 and H2 750 K's... etc while camped along the "Jack Pine Stretch" of the Moose Mountain Road in the Cambrian Shield of Northern Ontario - Them days are impossible today !

My friend with a 71 Ducati 750S along with my 70 Breganzie SF0 ruled that Mountain Road and we practiced with every chance we got. Nothing like the sound of two Italian Twins racing through the winding hills of the Cambrian Shield - Eat your heart out Japanese Motorcyclist ;o)
 
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I can assure you Ron I won't be grounding the starter relay through the neutral switch.
I've had 4 750s in the last 51 years and ridden hundred of thousands of miles on them and never had to replace a starter motor.
Maybe you should've serviced your starter clutch as something was amiss for it to grab at revs.

Thinking down the track I'll do a complete rewire using relays and reduce that mess behind the headlight.
It's a pain in the arse trying to refit the headlight.
As for reliability I can't remember ever having any wiring issues in the 43 years I've owned it.
 
Motoddrob; Your fortunate to have NEVER accidentally hit the Starter Button on a Lucas Switch at 7500rpm while gearing down from 3rd into 2nd with that flaky designed riveted Breganzie Starter Clutch. I was looking for the Turn Signal at the time and then POOF ;o)

All I'm telling everyone is how to prevent from blowing up the starter in early Breganzies without the Safety Starter Clutch Lever. Why do you think Motorcycle Electrical Circuits incorporated the Starter Safety Switch into the Clutch Lever if it were not for this reason other then accidentally starting the engine while the drive train is in gear ! It was not until about 1970 when Auto-Makers started to put safety switches on clutch pedals to prevent drivers from accidentally starting the engine while in gear.

Tell you the truth, I broke the shift selector plate in my 68 Volvo and could get into neutral other words the tranny was locked up in a drive gear - If I had to stop, I would push her into 1st and turn off the key - To get her rolling again I had to push in the clutch to engage the starter,turned the key to start the engine to get underway with battery power.

ARE TO STARTING TO GET THE PIC Motoddrob ;o)

I had a 74 Vplvo 240GL with Mechanical Fuel Injection that didn't even need a battery to get her running - All she need was a push. Granted not too healthy for the alternator diodes but it worked ;o)
 
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For that to have happened Ron as I said, something was amiss with your starter clutch.
You seem to be the only person who has had that problem from all the 750 owners I've known over the last 51 years of Laverda involvement.
I have accidentally hit the starter button on several occasions while riding without issues. If the clutch is working as it should it makes no difference.
 
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