Forum whore
Does the headlight run via a relay? Run good sized cables from the battery to the relay and light and all the wimpy contacts in the switchblock have to do is power the relay coil.
Or go to Pick-a-part and find HID lights and power supplies - if you can find one that would fit in your headlight (square IIRC)
it's not a bad thing till you throw a KLR into the mix.
those cheap ass bitches can do anything with ductape.
(PostalDave on ADVrider)
Bored Room
/\ /\ wot he said about the relays.
Ducati wiring is undersized and the earths are not great.
I fitted an LED to my old H4 BMW but the cut off for low beam is not that great.
Don't get brightness confused with colour, as different lights work on different spectrums.
Rewiring my Commando at the moment, all new electrics other than the switchgear which I'm only using to operate relays.
HID is not legal unless factory fitted AFAIK.
DeMyer's Laws - an argument that consists primarily of rambling quotes isn't worth bothering with.
Learning
Yep, what Pete said. It's the way to go. Just because I'm curious I went and had a trace through the wiring diagram.
The OEM ducati wiring loom has the following steps for the current to the headlight to take:
Battery terminal
Terminal block
30A fuse
Main relay
15A fuse
Terminal block
Headlight slide switch
High / low switch
High / low beam filaments
Headlight earth
Along the way there are also eight push-on crimp connectors for either high or low beams. The wiring for high beam uses two conductors running parallel, low beam just one - the wire is 2mm OD, including insulation. Throw in twenty years weathering and general degradation of wiring and contact points and no wonder it's struggling.
The use of relays would mean that high current would run:
Battery terminal
Dedicated fuse
Relay contacts
Headlight filament
Earth
There'd be six push-on crimp connectors and no terminal blocks. I could check the chosen wiring via thermal imager to make sure I'm not losing voltage due to light-duty cables.
Using relays will mean installing two, one for high beam, one for low, plus a fuse each. It'll be worth it I think... here's a copy-paste from Wikipedia:
Tungsten halogen lamps behave in a similar manner to other incandescent lamps when run on a different voltage. However the light output is reported as proportional to V to the power of 3 (i.e cubed), and the luminous efficacy proportional to V to the power of 1.3. The normal relationship regarding the lifetime is that it is proportional to V to the power of -14. For example, a bulb operated at 5% higher than its design voltage would produce about 15% more light, and the luminous efficacy would be about 6.5% higher, but would be expected to have only half the rated life.
Light output proportional to V cubed.
Playing with numbers again... let's say nominal voltage is 12V. What voltage drop does it take for light output to halve?
12 x 12 x 12 = 1,728
1,728 / 2 = 864
Cube root of 864 is 9.52 V.
In short, drop 2.5 V in bad wiring and that isn't roughly a fifth of the light intensity gone, it's halved.
Edit: I've bought some heavy-gauge automotive cable (Jaycar's off shelf offerings seems both higher quality and cheaper than Supercheap Auto) and had a play... early days yet but I reckon the way to size high current cabling is to build a system, measure voltage drops, decide to rebuild if needed. It looks like the commonly available wire size charts are written with sizes chosen against burnouts and catastrophic failures, not the ability to carry current without significant voltage drops.
Last edited by OddDuck; 7th May 2017 at 20:13. Reason: Notes about wire sizes
Learning
First go at fitting the cold-start system to the carburettor bowls.
I had to shorten a few of the pcb spacers. Before shortening, I used the existing threads as a guide for drilling and tapping, making sure there'd be enough thread for the cap screws. This left fine swarf in a blind hole, which is a pain - it'll jam up and lodge in threads if I try running a bolt in without clearing it. Blowing swarf out with the CRC worked though, a run-in of a cotton bud finished it off. I photo'd this the same way I did it, but I recommend gloves. Something in the CRC soaked into my skin, and I wouldn't do it this way twice.
There was a fair bit of filing to get the plates to bolt on. I had a few parallax errors with my original measurements. It looks like I'll have to put the heater retaining holes through a mill, as well - these need to be slots instead of holes. I want the heater elements to sit properly against one side of the carb bowl re-entry well, instead of skewed in the hole, and for that to happen the control surface has to be that well. It can't be the plate underneath.
Getting closer to testing... The orange tape on the carb bowl is there as a decent target for the thermal imager. I want to compare bowl temperature to what the thermostat contact probe reads.
Learning
Finally got around to something I've been wanting to do for a while - use thermally conductive epoxy on the threaded adaptors that the Keihin FCR41's use to connect to the inlet manifold rubber boots. The glue, courtesy of Atom Adhesives and Amazon, had arrived three weeks ago but I'd wanted a completely clear day to get stuck in to this particular job.
Doing this means that the adaptors are now connected permanently. That's fine; they've been on for years and there's been no service reason to take them off again.
The carburettors came off the bike reasonably quickly. I used earplugs (I like the 3M foam disposables, for some reason) on the fuel lines to stop gasoline splashing everywhere - wish I'd thought of this trick earlier. It saved a lot of mess. Once the carbs were on the bench, it was easy to put the fuel lines into a can and tip-tilt the carb bodies to drain fuel from the bowls.
Once off, it was a surprise to find both threaded adaptors were actually loose. Not rattle-loose, but close. Unscrewing the adaptors revealed beat-up remainders of PTFE tape in the threads and ingrained dirt, presumably pulled in under vacuum leakage. Not good, but it does provide some hints as to why the AFR reading has been doing some strange things at 1/8th throttle. There's been a serious hole in the mixture strength under sustained running at that throttle setting. This PTFE thread was continuous when I'd last assembled the adaptors so clearly it's degraded significantly over time and usage.
Cleaning time, pre epoxying. I scrubbed threads with an old toothbrush and methylated spirits (this takes dirt off without leaving a film behind on the surface, at least as far as I can see). Some of the dirt proved quite resilient and had to be taken out with the point of a knife, then I worked out a way to push the brush bristles onto the threads so that the bristle points were leading instead of trailing, trying to lift dirt out instead of brushing it deeper. Scrub, wipe with rag to try to transfer dirt into the matrix of the fabric, scrub again... got there in about an hour. I get one shot at this epoxying and I'd really like clean metal surfaces for this.
Learning
Right, time for an entire post about using epoxy to glue two carburettor adaptors in.
Basically, the thermal conduction part of this wonderstuff depends on contact area. It won't work as planned if it isn't over the entire surface area. Accordingly I had a couple of goes at this. It's slow-drying epoxy and is rated as workable for 60 minutes after mixing.
First try: carefully paint the adaptor threads, screw in, remove to check penetration and filling. Err... Nope. There was epoxy on the first few threads and then after that the metal had been wiped.
Second try: carefully paint adaptor (male) threads, then do the same to the carburettor body (female) threads. I used dabs of epoxy onto the blade of a flat screwdriver for this. The idea was that if epoxy is wiped off the back of the threads by the screwing-in action, it'll also be pushed forward as well, filling up the gap at the adaptor nose and demonstrating filling by beading out on the internal join as the adaptor is screwed home. The threads themselves should remain submerged, albeit with an air bubble or two.
This worked, as far as I can tell. Beading happened on both the inside and outside of the adaptors. Internal beading was very carefully wiped with single passes of a rag (use once, fold over, use again, fold again, etc), starting with the carburettor slide and then moving to the body wall and outwards. I was very careful to avoid pushing epoxy into the slow jet opening or the slide gate. External beading was cleaned up relatively easily with a folded rag, wiped around the perimeter.
The epoxy is rated at achieving 100% bond strength at 24 hours, if 20 C is maintained. Tonight will get colder than that, but I should be good to replace the carburettor bodies tomorrow night. I don't want to take the chance earlier, although it's solidified already.
Learning
Since the carburettors are on the bench and are accessible, I took a few minutes to fit the cold-start heaters and thermostat sensors.
The little tabbed bits of metal are bits of shim, cut with tinsnips and used as springs, to keep heater elements pressed up against one half-round of the elliptical bowl well (it's 6mm by 7mm).
No heatsink paste or thermal adhesive was used. The slow fuel jet screw is above this heater and I want to keep access, without breaking things or gooey heatsink paste going everywhere, every time I need to make an adjustment.
I've got provision for two sensors. At the moment the plan is to run one thermostat, driving both heaters in parallel, and assuming identical behaviour between carburettor bowls. This leaves the other sensor free for use as a monitor, or for some other temperature control arrangement.
Learning
Well, I've spent a frustrating week trying to source replacement oil cooler hoses for the cooler shift (online only so far, I'll scout the shops shortly).
I need -6 AN hoses:
hose 1 with one end straight, one end 90 deg, 450mm length
hose 2 with one end 45, other end 90, these are cross-plane and need to be rotatable, 500mm length
I've tried placing an order with these guys:
www.improvedracing.com
Lots of goodies. Unfortunately they've come back with a two-week delay due to waiting on parts.
Can anyone suggest a supplier local to Lower Hutt with walk-in service?
Bogeyman
Made to order is going to be a lot more expensive. But try Pirtek out in Porirua: http://www.pirtek.co.nz/pirtek-servi...?store_id=1505Originally Posted by OddDuck
Ring first, he's often out on a job. And I'm not sure he'll have access to rotatable ends...
Go soothingly on the grease mud, as there lurks the skid demon
Learning
Thanks Ocean1 - I've kept the order alive with the US supplier, mostly because the price is pretty reasonable for a pair of one-offs.
By chance I bumped across this seller on Trademe:
http://www.trademe.co.nz/Members/Lis...member=2307520
Lots of -AN oil cooler hose stuff for sale but it looks like he only lists ads sometimes. Hose, fittings, finishers etc. The advantage of going this way - DIY assembly - would be that hoses could be fitted to assemblies in progress, there wouldn't be any taking measurements and hoping that hoses fit when they turn up.
Anyway... slow progress on things electrical over the last few weeks. I've been having to learn the basics concerning auto wiring looms, my experience previous being bench mount / indoors stuff.
The first go at the controller's box for the carb bowl heaters didn't go so well. A few hours drilling, filing and fitting for various components, then I tried making permanent connections and promptly stuffed the switch. Soldering was fiddly, slow, melty (box and wire insulation), and finally it damaged the switch's rocker mechanism.
Previously I've been spoilt with switches made with bodies moulded in epoxy resin or similar. Even with push-on terminals, soldering is possible. Not so here; this particular impact-resistant plastic has a low melting or flow point and any hot work on the terminals is a bad idea.
Also, goodies didn't fit into the box. It's one thing to jig everything up on the bench and think, yeah, it'll be a bit cramped but I should be able to stuff it all in. Nope. Once the wiring starts going in, available space starts disappearing fast, then the roadblocks start appearing.
So, second try, using experience from the first go to redesign where necessary. The pictures say most of it. Work was sped up greatly by going from cordless hand drill to a drill press, using a step drill (for the 11mm holes needed for the short rubber grommets), and going to crimp connectors or clamp terminals throughout.
This was fired up today to check heating and control. Start temperature was 12 C, setpoint 27 C. This was achieved in around 1 minute, about the time I'd want to get helmet and gloves on, although I didn't time it. I did try starting without much luck, but the bike's been sitting for nearly three weeks now and the petrol isn't the best any more.
Learning
I increased the setpoint to 39 C and tried again. Much improved; even with stale petrol, the bike caught in a few cranks and held idle with the throttle lightly opened. It did take a couple of minutes to get to that temperature, though.
Got the headlights sorted today as well, finally. The relays and 25A-rated cable did the trick. The photo of the bike lighting up the garage door doesn't look different to previous - maybe worse, given that the wide spread of light seems to have disappeared - but the camera exposure has changed significantly.
Before relays: iso 500, 1.6 seconds, f/8.
After relays: iso 500, 0.3 seconds, f/8.
It's a far cry from a lightmeter measurement but as an indication it's pretty clear: light levels have at least doubled. Before I fitted the relays, I tried measuring voltage dropped in the loom with the old setup. Voltmeter A is checking battery voltage - roughly 11.5 V during test, with engine off - and voltmeter B is checking voltage at the bulb terminals - roughly 8.7 volts during test.
The OEM loom is dropping nearly 3 V. No wonder these bikes have a reputation for dim headlights.
A few notes about the relays installation, for anyone else contemplating a similar mod...
I used flyback diodes. These are arranged with the stripe toward the voltage signal line, i.e. blocking current when voltage is applied normally. Flyback, more commonly known as kickback, is the situation where supply voltage is suddenly switched off an energised coil. The coil attempts to maintain its field, so it fires a kickback voltage back into its circuit while the magnetic field is slowly collapsing. This voltage can be very high - a couple of hundred volts, even from these little relays - and if there are any semiconductors around, the spike can fry them. The same effect is used in ignition systems to drive a spark plug. The kickback diodes allow a reverse polarity current to run through the coil, safely dissipating the energy.
Probably I didn't need the diodes - automotive looms are supposed to be low impedance, with lots of leakage and stray capacitance to suppress voltage spikes - but if anything will be hurt by using them, it'll be the relay coils. These are a lot more replaceable than anything else on the wiring loom like switch contacts, the Rec-Reg unit, or my wideband AFR gauge, so flyback diodes it is.
The relays carry little 15A fuses on the high-current lines. This is very convenient, I don't have to install a fusebox somewhere or connect in-line fuse holders.
The relay sockets don't latch. I've resorted to strapping them onto the relays with cable ties. I really don't want these dropping off the relays during a ride.
The headlamp terminals are 8 x 0.8 mm spade lugs. I had to order these off Radiospares, not having any luck at Jaycar or Supercheap Auto. Maybe Repco do something, or someone knows an auto electrical supply specialist.
I had to branch the high-current lines - one relay for low beam, the other for high beam. This turned out to be more wire than a yellow butt crimp connector could fit, so I improvised a pair of crimps out of the flashing from the spade lugs and insulated with heatshrink.
The other note is about the polarity of the coils on the relays themselves. The convention is that positive goes to terminal 86, ground to terminal 85. This caught me out: the little diagram on the relay has 86 under 85, and every DC circuit diagram I've ever seen has positive voltage above ground, not below it. In theory it shouldn't matter. The coil isn't polarised, unless you've got a relay with a kickback diode already installed inside it.
Anyway, I've got the fairings back on, I want to test ride the engine to see what effect the thermal epoxy had on the carburettor adaptor tubes before making any other changes.
Learning
Took the bike out for a quick ride, ambient temperature cool but not cold - say around 12 C.
Cold start electric heater: worked a treat. No sustained cranking, no restarts. The engine caught after a couple of turns and held revs without any problems, even with 3-week old petrol.
Headlights: noticeably brighter, but it's the kind of thing that I'll get used to in about five minutes. No issues with high / low beam. One thing that I didn't expect was to have the instrument lights work better, as well... the speedo & tacho dials are now finally illuminated properly.
Carburettor adaptor epoxy: slight improvement in engine running and AFR consistency, not huge. I think it was necessary, but the major issue is to get some heat into the carburettors (in a controlled way) before fuel mixes with air, to get that petrol warmed up a bit.
Learning
A short post concerning something interesting I tried and tested today. It's cheap, it's easy, and it's well worth giving a go before spending serious dosh, if you're having issues with your bike.
Clean the connectors to your CDI's.
I'd been having trouble cold starting, issues with mixture strength as reported by the AFR gauge, and odd surges in power while running. It had been getting worse (very slowly), but yesterday the bike wouldn't start. I had the carburettor heaters on and warm carbies, turned the motor over until the battery started having problems, no joy whatever. Frustrating.
Slept on it, did some reading, had a think about what was cheapest and easiest to try first, and got the connectors to the CDI's unplugged and had a look at the push-fit terminals used. Ducati have used what look like the highest quality 3.2mm push fit spade lugs I've ever seen, they don't push on hard but they don't need to. There's a very nicely formed spring plate to ensure electrical contact.
The issue is the low voltage used to power the CDI's. 12 V isn't much and it doesn't take much dirt / oil / silicone gasket grease etc to interrupt it... guess what I waterproofed the CDI's cracked silicone potting with. Of course the silicone gasket grease has been migrating and it's got into the connectors, taking dirt with it and compromising the spade lugs contacts.
A quick spritz with CRC 2.26, make-and-break the connectors three times each, and try the bike like this with a freshly charged battery. Huge difference. The bike started easy (with carb heaters) and ran better than it has run in quite some time. Testing over the hill in the Wairarapa at roughly 10 C confirmed it.
I can't say it'll fix everything but for the cost of a can of CRC 2.26, it's well worth a try.
Forum whore
Standard diagnostic procedure (for me anyway) with computers and the like is to reseat connectors before replacing parts, with printers especially due to the constant vibration (eve worse in old style impact printers) resulting in fretting corrosion. Motorcycles could be considered a fairly harsh environment for connectors. Explained better here: https://www.researchgate.net/publica...cal_Connectors
it's not a bad thing till you throw a KLR into the mix.
those cheap ass bitches can do anything with ductape.
(PostalDave on ADVrider)
Learning
Might have had a bit of a result tonight... for several years I'd been considering the possibility that the CDI's aren't 100% any more. The bike's still running the original Kokusans and it's been twenty years. How to test a CDI (via the magic of Google) seemed to be limited to bike goes / bike doesn't go / witchcraft. The forums weren't very helpful.
So I did some reading and found that most CDI's work by charging a capacitor up and then firing a high voltage pulse through the coil's primary winding. The pulse is of the order of 250 to 600 V. The coil's secondary winding then steps the voltage up to the level where it can make a spark. The pulse isn't a nice, regular sinusoid or anything easy to measure with a standard handheld multimeter, but an oscilloscope might do it. There are a few of these floating around on Trademe; at $100-ish secondhand for old and thrashed they're a lot cheaper than buying a brand new CDI, which is the usual test.
A word of caution: make sure you don't blow the inputs. The one I borrowed from work was rated to 400V on input. I put the probes to 10X anyway, thus making input limits 4000 V, and set to with it like that.
Test procedure turned out to be simple: get a connection in to the lead connecting CDI and coil (stuff a wire in), clip into this and use the battery negative for a ground, then get bike started and check the trace once the engine was idling. I had to do some work with the settings to get a stable, measurable trace, but once set up it was quite repeatable. Results are pictured below. I got the same trace on vertical and horizontal cylinders, so there was no significant difference between CDI units. They're both putting out roughly 400V to the coil over a pulse duration of 8 micro-seconds, with lots of post-fire bouncing going on. Presumably that's inductance in the coil shooting back at the CDI... or something electrical like that. One of the neighbor's kids started making a fuss so I didn't rev the engine to see what happens at high RPM. Maybe on Saturday afternoon or something.
Anyway, the result is that I don't have to spend $$$ replacing CDI's, unless I want to go fancy and upgrade or something. The originals are still working just fine.
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