Running a relay race ……

So what is this new-fangled modification to the starter circuit I alluded to in the last post? Well in a nutshell it’s a new loom (plug’n play) that goes between the starter solenoid and the main loom and also goes to the battery. Why?

Aprilia Caponord ETV1000 Rally-Raid starter safety circuitAs mentioned previously, the starter solenoid draws about 2.9A when energised and that power goes from the battery via 2x 30A fuses, through the ignition switch on the headstock, then up to the fuse box in the cockpit and back to the starter solenoid. From here it goes via the diode block down to the engine (neutral switch) or side-stand switch (and back up into the loom) and all the way back to the handlebars (clutch switch) before finally making its way back to the battery via the main earth (Ground) cable – phew!!!! That’s a lot of cable and switches, never mind the diodes. OK the fact is, this circuit has worked trouble-free for 14 years, why mess with it? Because my gut instinct is that restricted power to the solenoid over time makes for low-speed actuation and eventually, burnt contacts …. that’s my theory anyway!

Aprilia Caponord ETV1000 Rally-Raid starter safety circuit - modifiedI figured an easy way to make sure the solenoid gets lashings of fresh volts/amps is to make the circuit between battery and starter solenoid shorter and simpler – so in goes a small loom with another relay, a 20A unit exactly the same as used for the headlights. This relay is now activated by the starter circuit and its contacts switch fused-battery power direct to/from the starter solenoid – short and sweet!

This relay has a coil resistance of 70Ω and so only draws 170ma @ 12V so no problem with starter buttons or switches getting a little resistive over time as (for example) a mere 0.5Ω difference when set against the 70Ω coil is only 0.7% difference compared against the 4.4Ω of the starter solenoid coil where a 0.5Ω difference equates to over 11% difference. Bottom line – the whole circuit has an easier time!

Aprilia Caponord ETV1000 Rally-Raid new loom and relay in starter circuit

The wiring is soldered direct to the relay spade connections and then slides into a 3D printed case and the case/contacts are encapsulated to keep the whole thing neat and tidy. Now the relay sits on top of the ECU held in place by a double-sided adhesive pad and the connectors tuck away neatly behind the battery.

If somewhere down the line it all turns belly-up, I only need to unplug the two connectors and reconnect the solenoid back to the main loom and it’s business as usual. So I figure I’ve got nothing to lose by giving it a whirl …… I’ll find out soon enough if it’s a thumbs-up or thumbs-down job!

John Walker (UK) – Power / Ground cable kit

Aprilia Caponord ETV1000 Rally-Raid John Walker power ground earth cable kitOk, so with the old starter solenoid removed and a little starter-circuit modification simmering in the old mental stewing-pot, it was time to remove the OEM solenoid-starter cable, along with the Earth(Ground) cable and the battery-solenoid-30A-fuses cable and fit the new upgraded items from John Walker (UK).

Removing the ground and starter cable required the removal of the crash bars and side panels along with lowering the sump guard (remove front bolts and pivot on rear) to allow extra room to lower the oil tank and move the oil cooler – both to illicit a little more room to remove nuts/bolts more easily with the tools at hand. With the respective ends disconnected it was just a matter of a few tie-wraps to be removed and the old cables slid out of the frame. The battery-starter cable requires a bit more work (care?) as the two wires to the 30A fuses need to be cut. These will be spliced with the new ones on John’s loom, so I carefully pulled the black sleeving back as far as possible, matched the old/new looms together then cut the cables at what seemed the sensible place!

Now with all three cables clear of the bike I could lay them out and compare them to John’s replacements. Not only am I impressed by the workmanship of the new cables, but also that they are approximately 15mm longer than the old ones – not over the top and certainly not too short, just nice – a little extra flexibility when fitting. One thing I really like about John’s cables is the extra mounting point on the Positive and Negative lugs – very useful indeed.

 

After lunch, in they went with no drama at all. I spliced the 30A cables together with crimp/solder joints that are then sheathed with heatshrink. John doesn’t provide the splices, but he does supply the heatshrink! With that done, the old black sleeve can be wiggled back up into place and the whole thing then looks very ‘OME’! Running the cables down the frame is easy enough as they’re quite flexible – surprising as they’re almost (if not more!) than twice the diameter of the old cables …… this does make things a little tight getting the cables in place either side of the battery, but a bit of patience and a wiggle here and there gets them seated comfortably.

Before tie-wrapping everything and refitting panels and guards it just left the little matter of trying it out! So ignition on …. no pop, bang or fire (good start!) then thumb the starter button and ………….wow! What a difference, the engine spins like a hyperactive puppy spotting its tail for the first time  – fantastic!  Putting the multimeter on the battery (fully charged), then cranking the motor over showed a minimum voltage (momentary as the starter takes the in-rush current) of about 10.8V. That’s way better than it used to be. Steady cranking voltage rises back up to about 11.8V…….. and as mentioned cranking speed is very impressive now!

With that done, it was time to button the rest of the bike back together and try it all out on the road. What a difference a week makes eh? From ‘Dear dog please start, please start …. oh and starter please disengage, pppplease disengage’ to ‘Oi you, call that a starter? …… Listen in awe my wayward friend because THIS is a starter!’

In the end did I really need them? Well truthfully, no the originals are fine, no corrosion and the insulation is intact, but at the time of ordering I really didn’t know one way or the other. Yes I could have made my own, but sometimes like having a meal served to you rather than cooking yourself, it’s nice to buy in the finished item ready to fit. Besides, I just wanted upgraded replacements not some fancy parts made from gold wire finer than badger bum-fluff with diamond encrusted unobtanium connections! In the end I’m glad I did buy them ….. the starting is much more energetic now and that’s worth its weight in gold right there!

So if you are in any doubt at all about your wiring, then drop John a line and I’m sure you  will also be as pleased as I am with the results. Price including postage in the UK (May 2017) is £70.00GBP

And now the dust settles …..

Aprilia Caponord ETV1000 Rally-Raid Yuasa YTX14H-BS batteryWith a hot brew to the left and a warm mouse to the right, I’m ready to reflect on the last ten days as the Capo sits outside soaking up the morning Abruzzo sun. After the hiccup at 138 miles the remainder of the 3,000 miles went perfectly, not one low-volt drama in sight. Mind you, that is with a new YTX14H-BS battery in the bike since last Thursday!

That same morning she’d sailed through her MOT with a clean sheet at 120,861 miles and now reads 122,135 miles at journeys end. Waiting in the panniers is a new Aprilia 150A starter solenoid (AP81129275) ordered online Aprilia Caponord ETV1000 Rally-Raid starter solenoid 150A AP81129275from Aprilia performance (UK) and deliver in 48Hrs which is great service, also a beautifully made power/ground cable kit from John Walker who pulled out the stops to make sure the kit reached me before we departed for Europe. More on this later.

So on reflection, what next for the dear old Capo? Well I’ll install the solenoid and cables over the next week or so and dig out the rear wheel/sprocket carrier bearings and seals, since a dull drone can be heard from the back wheel at about 50-70mph – and is getting steadily louder. There’s Aprilia Caponord ETV1000 Rally-Raid power/ground John Walker cable kitno play or sign of rust near the seal, but my guess is that one of the bearings is on the way out, so best do a touch of pre-emptive maintenance I think. 😀 

Highs and lows of the trip …… low, the DVSA. I can’t and don’t want to say anything on that front …… the high, yesterday afternoon, slicing through the late afternoon A14 traffic side by side with a new gen Caponord also two-up. We kept each other company for 20 minutes or so until he peeled off for Rimini, big smiles and waves all round! Great fun!!

And so, waffle over, without further adoo let the spanner twiddling begin! 😯