FAZ 600 - Time Warp 2004 Yamaha FZ6SA

[A_morti]

I always understood that Teflon-lined cables weren't supposed to be lubricated because oil made the Teflon swell.

Whether it'll cause a long-term problem or not is unknown, but working a few drips of oil down the cable has worked absolute wonders

[A_morti]

Throttle cables are also control cables, so per Mr Yamaha they need lubricating with engine oil.

Messy business, more so than on the clutch side due to the plastic end pieces, but worth it I reckon.

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The bike had a little bit of jerkiness off closed throttle before, but now I think it was just dry cables and is fixed. Tomorrow's commute will tell all.

[A_morti]

One day I'll buy a bike and dodge whatever known issues it has.

But this is not that bike

The bike has developed what feels like a 1 or 2 cylinder miss, so far only at idle, only infrequently, and only when fully warmed up.

The FZ6 has old school wasted spark ignition coil packs, although the corresponding R6 which donated the engine had coil on plug since 1999. The coil packs degrade with age (to be fair it's easy to forget the bike is 20 years old) and the spark takes an easier route to ground. Leave it like that a while, and it'll eat the driver in the ECU, bricking it and requiring a replacement lock cylinder, ECU, and coded key.

It's possible to fit the COP coils from an R6 (which appear to be the same part from 1999 until the last of them) and wire in series, so that's what I'll do.

[A_morti]

working a few drips of oil down the cable has worked absolute wonders

Temporary.
Temporary wonders.

Considering the plastic cover on the ball end was already broken off, I decided it wasn't worth trying any harder to save the 20 year old original cable and replaced it with an OEM FZ6N cable. That one doesn't have a tight metal bend at the top but is otherwise identical, and fits and works perfectly.

The FZ6 got its engine from the R6. Here's a dodgy R6 which has had a fight with a street, to show how the clutch cable runs the long way down on the RHS of the bike. Fine under racing fairings, not great on the Fazer's replacement.



Yamaha put a fair amount of effort into keeping the FZ6's side profile clean, which includes changing the clutch cover and cable. Result of that is it runs down from the handlebars tight along the inside of the left frame spar, under a bracket, through a clip, round a 90° corner, to a clutch pull pointing inward rather than forward. Looks good, but the bike has to come half apart for a new cable.

You can just see the cable peeking out between the frame and the throttle bodies on the LHS here while I was figuring out where that clip needed to be:

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Still, it's a pleasure working on such a clean bike, so I really didn't mind.

[A_morti]

It's possible to fit the COP coils from an R6 (which appear to be the same part from 1999 until the last of them) and wire in series, so that's what I'll do.

Gentlemens! Hold onto your hats.

I got the bike apart and the stick coils fitted in the holes well. Jules helped to make up a pair of pretty neat little sublooms, and we fitted it all together.

You can't really run the engine without fitting the airbox back on. So, with everything plugged in and the bike put back together to the point it was ready to go for a ride, the big moment was there.

Press the button...

The bike started and ran fine - but not for long at all, before dropping down to two cylinders.

Mr Haynes says the resistance spec for the fz6's ignition coil primary windings is 1.53-2.07Ω. My original coil packs measured at 2.3Ω on my cheapo multimeter. Deduct 0.3Ω as measured for the leads and (at least when they're at room temperature) they're in spec. On the other hand, turns out that 2003-05 R6 stick coils have but 0.8Ω (I measured 1.1Ω) resistance as a pair, so are definitely not in spec.

If I were smart and less eager to hear it run I'd have tested that before trying to start the bike, but I didn't.

By fitting those coils with insufficient resistance, I have now caused exactly the fault I had wanted to avoid by doing the modification: the ECU driver for coils 1&4 is burned out. I am sure of this diagnosis because the dashboard shows Code 33 (Open circuit coils 1&4) which cannot be cleared and stays with that circuit even when coil packs are swapped. I've checked the wire from the ECU to the coils, it's intact. So the only thing left is the ECU itself.

Turns out the coils I actually needed are from a more-recent R1, as those have 0.9Ω resistance a piece, so 1.8Ω on the pair, which would be in spec.

So the next job is to find a used ECU that isn't also bricked and an immobiliser eliminator, otherwise it's 1100€ at the dealership for a new ECU with matching ignition lock, key, tank lock cylinder and helmet lock. I'll also get the stick coils I should've got in the first place.

Before that I reckon it won't hurt to attack the ECU and try to see if there's an obviously-failed transistor or capacitor. It's all potted of course, but what's the harm in trying considering it's already fucked?

tl;dr: I was impatient /stupid, and bricked the bike.

Live and learn, eh?

[Taipan]

Shit! That is bad news! Fingers crossed you get it sorted cheaply!

[Skub]

Man,you've some bad fortune with bikes. I hope you get a result as cheaply as possible.

[A_morti]

The first set of coils came in cheap at around 50€ with the subloom, so in the end it's hopefully not going to have been too expensive of a game.

New ECU found in Italy for €77 shipped.

Immobiliser defeat ordered from UK... £40 free shipping if you're in UK, £61.35 if you have to add international postage and local VAT.

Still hunting the exact coils I need, but looks like €100ish should get the job done. 2015-2020 R1 coils are not as cheap as 1999-2005 R6 coils, who'd have thought?

[Bigyin]

You really dont have any good luck with bikes mate. My garage would just be a few piles of petrol soaked ash and melted aluminium if i had the same luck with bikes.

Good luck on fixing the fault as you seem to have a good grip on where to start and go. I am so glad my older Frazer has been a whole lot better behaved for me as the odo is now on 44,000 ish with 22,000 of that in the last 3 years of me owning it and only riding locally

[Taipan]

The first set of coils came in cheap at around 50€ with the subloom, so in the end it's hopefully not going to have been too expensive of a game.

New ECU found in Italy for €77 shipped.

Immobiliser defeat ordered from UK... £40 free shipping if you're in UK, £61.35 if you have to add international postage and local VAT.

Still hunting the exact coils I need, but looks like €100ish should get the job done. 2015-2020 R1 coils are not as cheap as 1999-2005 R6 coils, who'd have thought?

You didn’t pay that shipping did you?!?! Send it to me and I’ll send it recorded to you for free.

[Rockburner]

The first set of coils came in cheap at around 50€ with the subloom, so in the end it's hopefully not going to have been too expensive of a game.

New ECU found in Italy for €77 shipped.

Immobiliser defeat ordered from UK... £40 free shipping if you're in UK, £61.35 if you have to add international postage and local VAT.

Still hunting the exact coils I need, but looks like €100ish should get the job done. 2015-2020 R1 coils are not as cheap as 1999-2005 R6 coils, who'd have thought?

You didn’t pay that shipping did you?!?! Send it to me and I’ll send it recorded to you for free.

Don't do it!

It'll disappear into the Loft of Tat never to be seen again!

[A_morti]

You didn’t pay that shipping did you?!?! Send it to me and I’ll send it recorded to you for free.

I did.
Trouble is I'd still get caught on the duty, but also have to pay the post office's handling fee which should hopefully be avoided by doing it direct with eBay.

[A_morti]

The coils arrived from France, the primary resistance is about 2.1Ω across the pair, so they should be in spec for the fz6 ECU.

The ECU arrived from Italy. Looks the same, albeit with a different part / batch number on it.

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Can't test if it's the right one until the immobiliser defeat arrives from UK. It's currently on 'Item leaving the UK' but I don't know how long that'll be post-brexit.

Patience...

[A_morti]

New/used ECU and immobiliser eliminator installed, and the bike runs on 4 cylinders again!

I've decided to run it a few days with the original coil packs installed, just to see if the misfire when hot is still there. Unlikely maybe, but it's possible the fault was that the original ECU had a MOSFET on its last legs. That could explain why the driver for 1&4 died but the driver for 2&3 soldiered on. If it was just the low resistance in the coils, shouldn't both drivers have kicked the bucket together?

I'll likely still fit the r1 coils either way, since I have them now. But would be good to know if the old coils are good or bad.

[A_morti]

30°c here today. I took the traffic-y route home via the school to pick up my daughter (heat soak) and deliberately waited in line with everyone else. The fan cycled a good few times in 18 minutes urban riding after pickup.

It's been in worse traffic on hotter days but still: No stumble.

I'm still not really sure if it's not stumbled because it's not going to, or just because the specific conditions haven't been duplicated yet. Short of magicking up a 35+°c day I'm not sure how much closer I can match the conditions.

So, it seems the fault may have been in the ECU.

TBC...

[Taipan]

So a necessary purchase after all? That takes the sting out of it!

[A_morti]

So a necessary purchase after all? That takes the sting out of it!

I hadn't thought about it like that, but if the ECU was dying anyway, it'd let me off the hook as running the low resistance coils might have only been the final nail, rather than the single giant one.

[A_morti]

The bad news is the bike was misfiring like a mule today:


The audio isn't super clear (on phone speaker anyway, idk, with headphones maybe it will be) but any time it's dipping under 1260rpm, something ain't right. It gets down to 970, and feels like it will stall.

The good news is that I haven't fixed it by accident, and can now try the stick coils.

If it's not that, the owner's group suggests the TPS, a known issue that got early fz6s recalled, apparently.

[Taipan]

Fingers crossed you get it sorted. You could do with a bit of biking luck going your way!

[A_morti]

I could!
But then again, they do say you make your own luck, and I have bought a neglected outside dog, and a 20 year old antique.
So, there's that...