Page 1 of 1
#1 Bonnet plug wiring
Posted: Tue Nov 26, 2013 8:53 pm
by Dave K
Anyone tell me which wires go to what pins on the bonnet plug. I had a simple diagram years ago but after looking tonight it seems I have misplaced it.
I should have searched it out first before taking the wires out of the plg
Dave
#2
Posted: Tue Nov 26, 2013 9:20 pm
by 1954Etype
Dave they are on the wiring diagram - cunningly disguised as a number inside a circle which represents the pin number on the plug......
#3
Posted: Tue Nov 26, 2013 11:55 pm
by Dave K
Thanks Angus I have it now.
Dave
#4
Posted: Wed Nov 27, 2013 8:12 am
by 1954Etype
Its not that obvious until you know!
#5
Posted: Sun Dec 01, 2013 10:50 pm
by rfs1957
Dave,
I found this helpful ; it's showing what you see when looking at the
INSIDE of the plug/socket interface, so looking at the PINS,
NOT from the back of the plug/socket where the wires go in (which would be a mirror image of course) - it's potentially very confusing !
Down-load here.
https://www.dropbox.com/s/8pgyggulblig6 ... SOCKET.jpg
I think the new plugs/sockets available from SNGB for ?70 are an excellent copy, I'm really grateful that someone has bothered making them again, but unfortunately they copy all the faults of the originals such as a hopelessly weedy aluminium body to the car-side plug on the wiring harness, such that the ears that fold over the plug might as well be made from kitchen-foil.
This was on my car and I think it is an original one -
and this is the new one -
- where the ears are as soft as putty, and the plug won't stand being disconnected more than once.
The general machining of the pins is not very impressive, and the screw-threads for the little cross-screws is frankly awful - one of mine stripped as soon as its screw was tightened and I ended up fudging it by cutting an oversize thread, wherupon it then split. My fault, but didn't fancy waiting whilst I got it swapped for another that would have been just the same.
I would recommend this modification, which is tricky to achieve but makes it bullet-proof - no instructions, if you're capable of doing it then you can work it out ! There are just two places around the periphery where you can get a screw. I did a test on the old one to prove the principle -
then had a go on the new one -
It is essential that all the wires be twisted and tinned, then soaked in WD-40 upon assembly ; I even heat-shrank the outside to keep it all the screw-heads under compression. We motorcyclists end up quite OCD about corrosion/water-in-electrics etc

#6
Posted: Mon Dec 02, 2013 1:48 am
by PeterCrespin
rfs1957 wrote: We motorcyclists end up quite OCD about corrosion/water-in-electrics etc.
Well, Ducatistas do, and with good reason :-)
Nice Mach 1 is it in the background on the other thread?
Pete
#7
Posted: Mon Dec 02, 2013 7:58 am
by rfs1957
Ha ! Knew that would flush you out Mr Crespin ! It's a 477 (450 overbored to 90mm in a CrMo race-frame, Oldani rear, Ceriani 4LS front) sort of Spaggiari Replica.
#8
Posted: Mon Dec 02, 2013 10:29 am
by Heuer
Not sure tinning the ends of the wire with solder is a good idea. I was taught screw terminals and solder do not mix because the solder 'migrates' under pressure leaving the terminal loose. You see the effect on the terminals of bayonet cap bulbs and the manufacturers can tell how long the bulb has been installed by the amount of solder migration - they use the information in warranty claims.
#9
Posted: Mon Dec 02, 2013 11:28 am
by rfs1957
Thought you?d been quiet for a while David.
Wasn't aware of that phenomenen, but given the choice between single strands escaping up the sides of the screw point, contributing zero to the current-carrying capacity, and with bits falling out like a shower upon dismantling, which is what happens systematically when I use multi-strand cable, and being able to freeze the twist in solder and put some real torque on the screws, I know which has worked for me.
The oft-quoted Daniel Stern article also contains the comment that ?crimps ?. corrode and die? ; I can just about accept that factory produced crimping with machinery that is adapted and patiently adjusted to the insulation diameter, the exact core composition, and the exact connector type, is adequate ? if it?s also soaked in WD40 or some-such ? but none of the (expensive) tools that are sold for post-OEM modifications will produce predictable crimps of that quality, so I crimp then solder everything ? including bullets ? and then dunk the still-warm cable-end in a clear and runny wax-injection compound, or wipe a paint-brush-full down the shroud. The only proviso concerns serious vibration where the capillarity of solder going up the wiring core can give you ?stiff-necks? that concentrate the stresses and can produce hidden fractures within the insulation ???? but then that?s why I abandoned single-cylinders for six. And aren?t military helicopter harnesses soldered ?
PS - bullet and connector off 25-year-old harness, car never seen the rain etc ; hence why we used to tell customers to spend 6? on a can of WD40, open every cable/plug/connector (and pivot/switch/bracket and screw) on a new bike, and find the value was 20% higher in 5-years time .......
#10
Posted: Mon Dec 02, 2013 11:55 am
by Heuer
No argument with soldering spade connectors
after crimping although it should not be necessary if you use a quality crimping tool. Just don't solder the wires before you crimp them because the process is all about getting a gas tight seal between two metals, not three! As regards tinning wires before using them in screw terminals you only need to look at mains plugs - appliance manufacturers solder the ends of their cables and within weeks the screw terminals will be loose.

#11
Posted: Mon Dec 02, 2013 5:42 pm
by Dave K
Rory,
Thanks that's very helpful. You're original plug terminals at different from mine, mine are crimped where your are screw type fitting with slots to feed the wiring in.
Dave
#12
Posted: Mon Dec 02, 2013 5:52 pm
by rfs1957
Dave, If my "old" plug/socket are better than yours (they're virtually new) then why don't I send them to you ?

#13
Posted: Mon Dec 02, 2013 9:33 pm
by Dave K
Rory,
That would be great - thanks. I'll PM you.
Dave