Afternoon all. Dislodged wire

[Minto]

This is my first post on here but been reading for a while, astounded by the depth of collective knowledge on here.
I purchased my 52 plunger A10 about a month ago now and have been enjoying some short rides between work when it’s been dry. Unfortunate I can’t post a picture as im a tech numpty.
A couple of days ago I dropped the oil out, along with the sump plate and tank gauze, cleaned it all as well as the PRV I was shocked at the crap stuck to the end of the magnetic tank plug, and on the tank gauze filter, so decided that removing the tank to flush out would be wise.
Anyhow, being short on time was rushing and as I removed the top bolt on the tank, the battery succumbed to gravity and hit the deck, dislodging a wire from somewhere. I am buggered if I can find where it goes to. Now the electric won’t work, no horn, lights brake light nowt.
I’ll have another scratch of my head over the weekend, meanwhile any advise woul be appreciated.
The wire is black, has an eye crimped on, it’s cable tied to the frame down tube so it must be from close to that area.
Cheers folks

[Greybeard]

Hello Minto and welcome 

My first thunk about the loose wire would be the battery earth. If that is disconnected, there will be no lights, horn or charging. Although if you still use a magneto the engine should still run.

[bsa-bill]

Hi Minto
my thoughts echo those of GB, probably the earth, don't go trying it out as an earth though with out putting a bulb in the circuit - connect the black wire to a 6 volt bulb in a bulb holder of some kind (headlight maybe) then connect the other side of the bulb to the bike frame, if it lights up then it has completed a circuit

[Minto]

Hi and thanks for your replies.
I did try earthing it but still nowt, wondering if I damaged the battery when it fell, though it wasn’t a particularly hard knock that it took.
I’ve been looking at wiring diagrams for these bikes but can’t make my mind up which mine most resembles.
I’ll try to trace the other end of the wire, which goes under the fuel tank and beyond, see if I can work it out.
Going to test the battery when I get back from work too.
Sorry for posting in wrong section.
I’ll update as and when it’s sorted, or gets worse 😂

[Caretaker]

Moved from Intro board to Lucas\electrical.

Make a new intro post ? :O)

[duTch]

 

......The wire is black, has an eye crimped on, it’s cable tied to the frame down tube so it must be from close to that area....

 In agreement with the above, I suggest that the eye terminal was probably connected to the mounting bolt and came adrift when that was removed- (assuming it's the eye end that is not connected)

[Swarfcut]

Hi Minto, Welcome to the gathering of fellow sufferers, the best Forum by far for your bike.

 Basic Electrics.... In standard layout, early models like yours have the horn and brake light wired directly from the battery. The power for these goes nowhere near the ammeter and main switch. So, check there is still life in the battery, then look for the battery connections....The non earthed terminal  will feed directly to the horn and stop lamp. This battery terminal  also feeds the into main loom, connected first to the ammeter,  then from the other side of the ammeter it divides into a feed to the main switch and a wire to the and the regulator box, terminal A You can run the bike without the battery, the lights should still work.

 The battery earth terminal needs to be connected to the frame, making sure there is good electrical contact. The wire you have with the eye crimped on could be this wire, or the earth return coming back from the brake light switch.

 So once the battery is re connected, horn and brake light should work. Providing the rest of the system has not been messed with, all should be back to normal.

 Easy mods. Add an in line 10 amp fuse to that battery earth wire...it will save the wiring from frying when you get that inevitable short circuit.  A supplementary earth wire added from the battery earth terminal to the headlamp earth connection will improve the set up, and may remedy poor lights as normally the only earth return from the forks is through the grease filled headstock bearings.

 Engine...Always have a look in the oil tank before starting up, the oil level can drop alarmingly on standing. This is known as wet sumping, and is a well documented characteristic of this this engine. The usual remedy is to drain the sump, filter out the bits, put the oil back in the tank. Lots more on the Forum.
  Once running, there should be a strong oil return flow, which varies from big gulps to a dynamic stream, it all depends how much oil needs to be scavenged from the sump.

 All the best.

 Swarfy.

[Minto]

Thanks for that hugely informative and enlightening reply, I think the wiring might’ve been altered from standard, in line fuse there already, new wires etc. Hopefully it’s just sensible mods rather than butchering and bodging.
I’ve not had chance to look at it yet (work getting in the way as usual) but hopefully will get chance Monday.
There’s good oil return, and it has what seems to be normal residual in the sump after both oil changes. 150-200ml and clean. Phew!
Cheers
Jase

[Minto]

Morning all
Well, armed with your knowledge and advice I hit the garage early this morning, the dislodged wire was indeed an earth but that wasn’t the problem. As the battery fell it had broken another wire inside the sheathing, hadn’t seen this the other day cos the sheathing was still intact. Anyway, 20 minutes playing and everything is working again
Thanks very much to you all.
Jase

[Greybeard]

Minto, sorry to rain on your parade but you need to research sludge traps: https://www.a7a10.net/forum/index.php?topic=12335.msg96320#msg96320

[Swarfcut]

Minto  Good to know you have success. I mentioned wet sumping was a well documented characteristic of the design, but as GB indicates, another well documented characteristic is to explode in a spectacular manner, usually when wringing its neck within an inch of its life. Over many years, few oil changes and general neglect, the products of combustion etc accumulate in the crank oilway between the big end journals, to form a hard sludge which blocks the oil supply to the drive side big end bearing. The result is spectacular as the conrod exits the crankcase.

 So despite the doom and gloom, ridden gently you should be OK. But for any peace of mind and trouble free long term ownership, I would strongly recommend a complete strip down and a clear out of the crankshaft sludge trap. Lots of information on this forum, and the bits you will need, gaskets, possibly new sludge trap plugs etc are all readily available.

 These engines are a rugged design, and will tolerate a lot of general wear and still perform adequately. While true mechanical perfection at a price is very nice, bear in mind how much riding and use you will get out of it. It can easily run away with your cash.

 Treat it gently for now, get to know it, get some fun. Budget for a major overhaul sooner rather than later when it has gone bang.

 Online, "Sump Magazine" has an excellent profile of the A10 Golden Flash, well worth a look.

 Swarfy.

[a10 gf]

Request... :O) this topic is about a "Dislodged wire", engine subjects goes in a topic in "A7 & A10 Engine". Thanks!

Ref https://www.a7a10.net/forum/index.php?topic=4457.msg47773#msg47773

[Minto]

Yeah, erm, well, looks like a rebuild on the cards then.
Id read about the crank sludge trap previously, and planned on stripping the engine over winter anyway, just to be sure.
I’m not into thrashing the old girl, I’ve got a middle aged Italian mistress who seems to enjoy a good spanking, so the bsa is for enjoying the scenery on.
I am going to be somewhat paranoid about it going bang until it’s done now though, but really can’t spare the time to do it til winter.
Thanks for the heads up
Jase