A close call.

[Mr Gazza]

I usually keep a regular check on my charging circuit connections.
Last Winter was so mild that I didn't ever really get round to a proper Winter overhaul. I just kept using the bike.
This afternoon I decided that it was high time I fitted the Gold connectors that I had promised for a long time.
This is what I found.
https://s21.postimg.org/54yq0vflj/burnt_wire.jpg (https://postimg.org/image/mv0elwt6b/)[/url]

I think I broke what was left of the terminal when I was tugging at the harness to find the connector. But even so it wasn't hanging on by much.
A classic case of the ol' high resistance joint!!

https://s10.postimg.org/z3zgry7zd/burnt_connector.jpg (https://postimage.org/app.php)[url=https://postimage.org/]

A little bit of corrosion inside the connection is all it takes.. Possibly a result of a 90 mile ride in torrential rain late last year? Or just nature taking it's course.
Either way I'm glad I checked and I'm regretting missing the check last year.

Well it's all fixed now with soldered on Gold connectors and pending a reg/rec test. The battery seems all good.

Just to say, don't take these connections for granted... Give them an annual check or they will kill your Reg/Rec and then your battery.

[Fuzzy]

Where did you get the gold connectors??? I'd be interested in getting a full set for my 821.. spend so much time in the wet n crappy roads (worst half of winter and again now as a commuter) have ordered a ton of titanium bits to replace the corroded nuts n bolts, when I can find someone to flash and map the ECU it'll get its titanium pipes too before being put away on a wet day haha

[Cobra88]

Just in time Gazza

[Mr Gazza]

I get my Gold connectors from the local model shop. They come in a few different designs and sizes. Don't use any smaller than 4mm.
Usually sold in male/female pairs with heatshrink included.

Gold is a noble metal, so won't corrode, and makes an extremely good electrical connection, but the next weak link is the part of the cable next to the solder at the back of the connector. Flux residue seems to help rot the conductor at this point, so it's important to try and remove or avoid flux here, and then make the best effort to protect it from water.
Utopia knows of some heatshrink with hot melt glue inside it which sounds good?

Kato also found some good quality waterproof connectors from Triumph, which you can fit as a kit... I'll try and find the link.

By the way a ton of Titanium is a helluva lot of metal. I think you will slow your bike down if you fit that much...

Edit... Found the link.. Some very interesting reading here if you are thinking how you can improve your electrics. Good ol' Kato. http://www.ukmonster.co.uk/monster/showthread.php?t=46708

[emzedder]

My 900SS caught fire on way home from work a few years back. The starter solenoid jumped its mounting and the terminal grounded on the cylinder causing the overheating wire to ignite. I only noticed because the motor cut out at around 40mph. Stupidly I only thought of saving the bike so hinged up the tank and patted out the fire with my gloves ... never considered the exploding tank scenario at the time!

Battery terminal was molten, got her home and fitted a new battery and lead and all been fine for the past 5 years-odd ... tough old girl.

[Darren69]

I've seen this problem so many times with different Ducatis over the years, it gets tiresome. Something isn't right with the plug, its inadequate to deal with the current, we know the wires are just about capable. Where is the Reg/rec located on the 900Sie Gazza? If its under the seat the same as the S4 then it will get too hot and may cause this issue because of heat build up in the unit which in turn I think would heat the wires.

Ducatis answer over the years at least with the 748 and 916 was to change the plug to that type you have that failed was tp add beefier wiring and a larger heat sink to the reg/rec and a vent in the fairing lower to direct air onto the reg/rec unit. All have made improvements but not solved the issue completely. So I'm wondering if the problem is caused by a combination of poor connector which adds resistance and heat to the plug AND heat build up in the reg/rec and wires due to poor ventilation.

I'm going to be checking and cleaning mine in the next week or so but I have already relocated my reg/rec flipping in over and into more air flow, where it is noticeably cooler. I have lost count of the number of such failures from my 748 where the reg/rec is bolted to the front cylinder head, and just down wind from the front exhaust where it is always going to be too hot.

[Mr Gazza]

Blimey emzedder that so on topic... A Close Call. Were your gloves alright?.. :mand:

Yes Darren it is so boringly repetitive how many times this issue comes up.
The Sie R/R is on the front of the frame, nicely in the airflow. But I think that the problem is started off by a high resistance connection.

I remember fitting an upgrade three phase alternator to some bike or other years ago. The instructions stressed the importance of low resistance connections to the rectifier, and described ways of achieving this. I didn't fully understand the electrical terminology at the time, so I looked it all up.
You need low resistance to make it easy for the current to flow. When it meets resistance it makes heat and causes failures like that pictured above.
Low resistance means a large cross section of conductor throughout the circuit.
High resistance is caused by dirty loose or corroded connections, or connectors that are too thin and have little contact area.. In other words anything that reduces the cross section of the conductor.

Yes indeed all very boring, but I posted this up just to remind folk that even if you know the story and keep an eye on your connections.. Turn your back for a second and it bites your arse.!!

[emzedder]

I generally wear German Luftwaffe gloves so have a good provenance!

[Mr Gazza]

Das ist gut. :thumbsup:

[Nickj]

Something like MT60 connectors would be good and would give a good overhead for this. They're rated for more than more than enough current, you don't get a neat block connection but nice sealed connections.

[Fuzzy]

Wonder if I could get the dealership to swap the connectors over... half way home this morning my dash lit up like a Christmas tree with TPS error, ABS error, yellow flash on the dash, faults cleared, then came back... did it for about 4 miles before it sorted its self out... put it down water ingress with heavy rain and driving wind... (Cumbria what can you say... sooner I can get a car the better)

[Dukedesmo]

My old style single phase Monster has 2 large bullet connectors on the cable from the alternator, the RR was supplied with a cable that adapted them to a square white plug but I did away with it and just use the bullets direct.

I mounted the RR onto a large aluminium plate, directly in the airflow that acts as both heat sink and air deflector to keep the crap off the vertical carb filter.

[utopia]

My alternator to reg/rec connector did the same thing a few years ago ... except it was even more melted.
It was actually on one of the hottest days we've had in recent years, but I had only gone literally a mile down the road, to my local nuts and bolts emporium.
I smelled burning on arrival and I remember asking the shopkeeper if he'd been having a bonfire.
Bike wouldn't start when I left, though bizarrely it bump started easily enough and I went straight back home to investigate further.
The same bonfire smell greeted me when I got home so I knew then that it was me.

Reg/rec alternator and battery were all fine, you'll be relieved to hear, Gazza.
I have since re-routed the cables so that the offending connection is exposed and easily inspectable just below the tank, left hand side.
The connections are also now hardwired.
I used homemade crimps fashioned from thin copper sheet which I formed into a tubular shape around a fat sewing needle .. two wraps.
After crimping I covered each one with glue-lined shrinkwrap (Kay's fasteners - ebay).
The glue not only seals the joint against moisture but also provides additional mechanical strength.
I don't like soldered joints because, as Gazza points out, they create an adjacent weak point, either due to flux residue or simply the sudden change from flexible to dead rigid.
But meths will clean off rosin flux, if you must solder.

Gazza .. I'll make you some crimps and bring them, along with some glue lined shrinkwrap, to Grumpy's forthcoming meet, if you like.
Which reminds me, I promised Jerry some ages ago .. I'll make both sets while I'm at it (I still have your address I think, Jerry).

One alternative to crimps is Delphi Metri-Pack 630 series multi-connectors from Kojaycat .. rated at 46 amps.

[jerry]

OK good on you

[Mr Gazza]

Thank you Jeff, you are a gentleman... Looking forward to Saturday.
Weather looks like it will be acceptable.. Just hope I can get the bike back together.

[Darren69]

Mr Gazza, in light of your recent discovery I thought it was high time I gave mine a quick once over to check for any issues and just give the plug and connectors a good clean. The wires seemed in good order, no charring and the plug looked fine too. I separated the plug and gave the connectors a good clean with contact cleaner, the male plug on the reg/rec side I was able to clean with a cotton buds but the female side on the loom side just had a good spraying. It's this side that concerns me since there appears to be some staining from what I think is rust visible through the plug. I think its only a matter of time before it will fail, as they do. What did you do on yours? Cut the plug and replace with something else? Do you have photos? For the time being I just want to nip this problem in the bud and make good with the hardware I have without going to the expense of a Mosfet unit.

[Mr Gazza]

I'm glad you posted this up Darren. The very reason I started this thread was to draw as many peoples attention as possible to this issue, so maybe we read fewer stories of fried reg/recs and boiled or dead batteries.

Possibly the best preventative maintenance anyone can do on a Monster is to check these connections and make them good.

I swapped my standard (knackered) connector block with Gold bullet connectors from the world of aero modelling.

https://s29.postimg.org/4r2nl5duf/gold.jpg (https://postimg.org/image/rsj8qwdhv/)

They need to be soldered onto the original cables. Gold solders beautifully but you might need to cut back the cables to get nice bright metal if any corrosion has crept down there.

I fill the little scoop on the end of the Gold bullet, with solder and tin the end of the cable. I then quickly re-melt both and plunge them together.
Apply heatshrink to the female bullet making sure that it covers the whole thing but leaves the hole open. Then push the male and female together and bring the heatshrink on the male bullet, right up to that on the female and shrink it on. (I use the thick body of my soldering iron for this, but a lighter flame is traditional).

The bullets I used were 6mm and have an anti-vibration barb in them, but there are many types.
From memory I think we used to reckon that 4mm bullets were good for 50amps, but any fool can see that 6mm is way good enough, having a contact area more than equivalent to the conductor cross section.

I cut and "bulleted" each cable one at a time, so as to keep the same cables connected (I don't know if the phases have to be connected in any particular way, but if you keep them the same then no worries!) I also staggered the lengths of the joins so the bullets don't all lie together, reducing the risk of a short and also making it easier to re-connect in the original sequence.
Finally cable tie the harness each side of the connections, to the frame so they can't separate in service.

[Mr Gazza]

Just a note on why I used Gold bullets.

Some ready-to-fly model aeroplanes use battery connectors very similar to the original Ducati connector blocks with brass or ferrous lucars (spades) inside them.
These do not provide a good low resistance connection and are prone to corrosion and vibration.
Evidence of this comes in the form of RF interference. Tiny little sparks jumping across gaps in the connections emit radio noise, in the same way that you can hear a lighting bolt on your radio.
This is highly undesirable in a radio controlled model and has caused many a crash.
The cure is to use tight, vibration resistant, Gold connections. Then you have a good clean, low resistance connection.

RF noise on a motorcycle is not a problem that I have heard of, I am just using the RF issue as evidence of a good test for a connection. It also just happens that Gold is a noble metal and does not corrode. So this a distinct advantage for a long lasting job.

[Dirty]

Does it kill werewolves?

[utopia]

Hang on though .. you can't be saying that you bought 10 pairs of solid gold bullet connectors for just £12.99 ......?
These are surely gold plated, aren't they ?

Anyway, for me the weak point in that system is the solder.
Or more specifically, the sudden change in stiffness between the soldered area and the adjacent plain wire.
In my experience, this always becomes a fail point sooner or later.
Might I suggest a small mod viz using hot-melt glue lined shrinkwrap to bridge (and reinforce) the gap between bullet and cable ?

When my reg/rec first went I was a little horrified by the suggestion to hardwire the connection.
It seemed crude and just not "proper".
However having done it, and subsequently enjoyed a reliable charging system, I've changed my opinion.
Of course there are good and bad ways of doing it and many pots of tea were drunk in the "thinking about it".
An obvious point of jarring concerns subsequent disconnecting and wire lost in the cutting.
So I made my own mini butt crimps (pause to chuckle), to avoid the use of solder for the reason given earlier as well as making disconnection a tad easier with less cutting losses.
I cut some strips of very thin copper sheet, about 10mm wide and wrapped them around the shank of a carefully selected drill, in a double thickness, ending up with little tubes 10mm long.
The yellow wires were then bared to 10mm and inserted 5mm each, ie 'til they touched in the middle. then by twisting to and fro while continuing to push, the strands of wire on each side were encouraged to mesh together (like a pair of shoe polishing brushes .. or stickle bricks ..?). .. the carefully selected drill allowed just enough room for this in the bore of the crimps.
The end result is the cable insulation butting snugly up to the crimp tube at each end.
The tubes themselves are not much bigger in diameter than the cable insulation, so the whole thing is relatively smooth and very simple.
I crimped it with a plain crimper rather than one with a "w" shape, so just squashed it evenly all round really.
The interlocking of the strands gives me confidence that the electrons will hardly even notice the join.
And then of course the essential mechanical strength, with a bonus of sealing against moisture, is provided by covering the whole lot with a 25mm length of the hot-melt glue lined shrinktube, which transfers any flexing stress to the insulation rather than the connection or the wire itself.

In the event of subsequent need to disconnect I reckon I could undo that lot and the absolute most I would lose would be the 1cm wide connecting strands .. might even save those though its perhaps not wise.
But its a trouble free joint so those occasions would be few and far between anyway.
And as it happens, I re-routed the wiring to the left side of the bike and thus released plenty of spare wire to cover cutting losses, should they occur.
Funnily enough I initially did this so I could position the newly made connections out in the open where I could keep an eye on them .. this was immediately following my totally toasted original connector and I was nervous.
They have survived the exposure in all weathers for a couple of years now, with total integrity.

ps. you can buy crimps covered in glue lined shrinkwrap but you damage the wrap in the crimping and they're too bulky anyway.

You pays yer money and takes yer choice I guess.
There's more than one good way to do it.

[Darren69]

Do they do something similar that can be crimped. My soldering skills might not be up to it. I can tin the wires and do crimps but before I go down that route I'm also wondering if there might be a plug that is better and more up to the job, there must be something in the auto electrical world that suits surely?

[Mr Gazza]

Yes they must only be plated, going on the weight alone.
Gold plated Aluminium I would imagine... So a noble metal on a lightweight substrate... Win win.

Thank you again for the set of your home crafted crimps that you gave me.
They are a well thought out alternative solution to the issue.
You are absolutely right about the solder. It does make a potential weak link at the point where the tinned portion of cable ends. Both for the leverage reason that you state and also due to the apparent corrosive nature of any residual flux.

I ty to clean off as much flux as possible before making sure that area is well protected from the elements with heat shrink, and then further protecting from vibration by strapping it down securely.

Your crimps are a far better way to hard wire the joints than by soldering, as the above problem would still exist with the solder.

I wasn't quite brave enough to hard wire the joints, but I will still have to change the terminals on the rectifier cables, should I ever have to replace it. So no saving there.

Anything is better than ignoring the connections... Still not checked yours yet gentle reader?