Whacky electrics and backfiring.
 

Ey up,

I've got a right stinker of an intermittent fault on my SV. It's an '03 plate but still a K2 model. Currently 22k on the clock. I've searched and read previous threads but nothing matches my problem exactly. Apologies for the hefty rant here but most of this is cut and paste from a report I produced for my bike shop (knowing what intermittent faults are like).

· Friday April 3rd. Collected bike from shop after having rear suspension shock replaced. Bike started fine, however as I started to manoeuvre the bike out of the garage I noticed that both dial needles were fluctuating, the LCD display was full of characters, and the low fuel warning light was on. Assumed that battery voltage could be low after having work carried out. Switched off headlights and all symptoms returned to normal. Rode bike home, plus an extra few miles. Ran bike on drive for several minutes to ‘top up battery’, before shutting down for the weekend.
· Tuesday 7th April. Rode to work (20 miles) no problems. Set of home that afternoon. 2 miles into journey, attempted to overtake in third gear and bike began to kangaroo. Power delivery very erratic. Looked down and noticed instruments doing same as before. Switched headlights off and things seemed to calm down.
· A further 2 miles on, whilst accelerating out of a bend, problem re-occurred. Lights already off, so had no option but to ease off. Problem seemed lessened at low revs but re-occurred whenever power demanded. Like it didn’t have the current to supply the spark. Whilst going uphill, forced to change right down to keep bike alive. Whilst at a crawl in 1st, all symptoms cleared and managed to complete journey, albeit nervously.
· Put battery on charge. Charger indicated battery was already fully charged. Checked condition of all fuses on driveway. One looked a bit dicky so swapped around. Various tests, bike appeared ok. Rode bike to and from work the following day. No issues.
· 3 days good riding round Trough of Bowland the following week. No issues.
· Tuesday 21st April. Riding to work in the morning. 10 miles into journey, problem occurred whilst accelerating uphill in 4th gear. Eased off and bike settled down again. 4 miles later, in 30 zone problems again whilst just at low revs. Changed down and pulled over. Whilst in neutral, dials still flicking, LCD display full, fuel light on. Exhaust backfired :smt071 and engine cut out. Waited a few moments, started up again. No apparent problems. Completed remainder of journey.
· Rode home that night without incident. Replaced all fuses with new.
· Rode Wed Thur and Fri morning without incident.
· Returning home Fri afternoon, 3 miles into journey, problem occurred at low speed. Whilst changing down gears, engine cut out whilst still moving. Coasted to a halt. No lights or indications at all. Electrics appeared completely dead. Turned ignition off and back on. Still lifeless. Removed key.
· A minute or so later, whilst gathering my thoughts I noticed the indicators flash to indicate the immobiliser had enabled. Cleared with fob and put key in. Systems ok. Started engine. Fired, run for a few seconds. Cut out. Electrics down again.
· Waited a minute or so again. Put key in. Had electrics but neutral lamp was flickering. Started engine fine. (Starter sounded healthy and right speed, not slow or laboured). Engine fired. Caught. Dials going haywire. Cut out. Dead electrics again. This time could not get any signs of life again no matter what I tried.

• Collected the bike from the ditch point. After spending the night in a very kind persons garage the bike electrics lit up and started ok. By the time I'd ridden it 30yds to the waiting trailer, the needles were thrashing and the engine spluttering. Only just got it on the trailer under power.
• Delivered bike to the shop. Ran it for 5 mins. Would not demonstrate the fault to the owner.
• Left bike with them, plus the fault report. they've checked the electrics, all connections appear to be sound and no signs of cables rubbing or arcing. Regulator output is a healthy voltage even when the headlights are on. No issues with charging. Over the space of 4 weeks they've took it out on short rides (15 mile) and it has behaved itself perfectly. Mechanic yet to witness the fault in action. On the assumption that I couldn't leave it in the shop any longer I got them to carry out a full service on it and then I settled up and took it off their hands.
• Following day I rode out to visit family.45 mile - 20mins major A-road plus 20mins motorway. No problems at all.
• Return journey, only got 100 yds and whilst in second gear I felt a splutter. Ditched the clutch and looked down. Engine still running but fuel light on solid. Whilst rolling I let the clutch back out slowly after the light had gone out again. Continued journey.
• After the motorway leg I then picked up the A-road. Whilst demanding a little power to overtake a dawdler (~60mph) I felt a splutter. Instinctively I ditched the clutch and eased off the throttle. By this time the engine gave an almighty backfire. :smt071 Looked down and engine had cut out. Electrics appeared ok. Still rolling, I managed to re-start the engine and continue. Made it home without further incident. So glad that the last cough happend in light traffic on A-road, rather than the 4th lane of the M6.

So, having paid ~£250 for the extended stay in the shop, I'm no better off really. They have no idea what's causing it. I'm supposed to be going on holiday on it in 2 weeks but I have no confidence in it's relaiability.

I feel I have 2 options;

1. Keep chucking money at it. Eventually a component or something will get changed and right things.
2. Trade the bike in.
   

The way I'm feeling, option 2 is looking favourable but I feel that if the fault were to occur on a new owner, unawares, at the wrong speed, heavy traffic - the result could be extremely dangerous. That doesn't sit well with me.

Anyone had anything like this before?

Cheers,

Bunks

Re: Whacky electrics and backfiring.
 

Trade it in. :D

Re: Whacky electrics and backfiring.
 

remove the immobiliser and see how it goes.

Re: Whacky electrics and backfiring.
 

Thanks Husky. Will deffo consider that. The immob's been a little twitchy in the past. If the fob sensor gets very wet (i.e. washed), it wont read the fob right and will not disarm the immob. Riding conditions whenever the fault has occurred has always been dry (but not particularly warm).

Re: Whacky electrics and backfiring.
 

This could take several days to get organised, so would appreciate any other nuggets of wisdom in the meantime.

Re: Whacky electrics and backfiring.
 

calling yc

Re: Whacky electrics and backfiring.
 

I'd have a look at the starter relay - the one with the 30A blade fuse on. It might be the ignition something, I'm not sure what it's called, but if you take the seat and the side panels off, it's the bit on the right hand side of the bike with the green cap on it. Pop that cap off, unscrew it and have a look at it (it's in a little rubber housing). Check to see if the metal on it is all green- if it is, give it a clean up and put it back on the bike, check the fuse, while you're at it, check all the fuses.

See what happens.

Re: Whacky electrics and backfiring.
 

Loose connector somewhere. Start with everything near the shock. Battery connections, starter relay etc etc. I've had the same symptoms simply with a starter relay connector that had worked loose.
Edit: Yes listen to chakraist about starter relay.

That's after you get rid of the immobiliser. It will take someone who knows one end of an SV loom from the other 45 minutes. Secure as f#ck eh.

I would offer to sort it but have exams, can have a look after 1st june.

Re: Whacky electrics and backfiring.
 

Sounds like problem Joshmac has

Re: Whacky electrics and backfiring.
 

Similar, except my electrics all stay on.. :confused: Too intermittent to trace though. When it comes back I'll try stripping it down and check and clean all the connectors. Also, my bike doesn't always start after it dies. I've drained the battery a few times trying.. all in the last week or so. Seems OK at the moment though :rolleyes:

Re: Whacky electrics and backfiring.
 

Cheers guys.

I've already replaced all the fuses in the main box with brand new ones, even though none had ever blown and all looked in acceptable condition.

I've read similar threads where the starter relay was the cause. Aparently everything runs through that. And they can go a bit flaky with old age. Symptoms were never quite the same and some guys were claiming it was actually the clocks in the end.

Looking at ebay, can pay up to £35 for a used/salvaged one. Probably all as old as mine and no guarantee it's not going to go mental iteself in a few months. I've seen a new relay for £46. That's not a bad price for piece of mind.

I'll phone the shop this morning. Get them to order me a relay and book in for that and immobiliser disconection.

Yorkie - thanks for the offer. I should be able to get it sorted with the shop in time for my big ride (11th June). If not, I'd like to take you up on it and buy you breakfast. Assuming the bike makes the journey that is ;)

Re: Whacky electrics and backfiring.
 

Second that. I had a similar problem with my SV a few years ago. It took me ages to find the source of the problem. It turned out that the main fuse holder on the starter relay was seriously corroded and literally fell apart when I dismantled it for inspection.

Re: Whacky electrics and backfiring.
 

What's the Starter got to do with it once the bike is ruining? genuinely :confused:

Re: Whacky electrics and backfiring.
 

The starter relay also contains the fuse holder for the main fuse. It's the fuse holder that can be the problem. If it's very corroded it will not be able to deliver enough amps to power the bike. Voltage will then drop and clocks, ignition etc will stop working properly.

Re: Whacky electrics and backfiring.
 

As skumerlud says, all power for the loom goes through the main relay. There are 3 connections to relay, 2 of them are for the solenoid to fire the starter, the other one is a red wire that goes up to the fusebox and supplies everything.

Re: Whacky electrics and backfiring.
 

Ok I've got the old starter relay in front of me.

Some blue corrosion on the main nut terminals. The 30A fuse looks in good health but there's some furring on the blades, same in the fuse holder. However, the 4 connector block pins are corroded, plus additional paricles of corrosion building up between the pins.

One pin is on it's last legs. Just a light touch and it bends. I suspect there's not much left at the base of it. That would have been severely limiting current.

I think we have the culprit. Brand new relay installed and the immobiliser's off too.

Will give you gents a sit-rep post first big ride.

Re: Whacky electrics and backfiring.
 

my k3 did exactly what you described, only i noticed before any of the backfiring/cutting out that it was idleing at about 1000rpm rather than the usual 1.5k, the only thing i did when it cut out was leave it swtiched off at the side of the road for about 10mins... then drove it to a garage and filled it up with super unleaded. Few days later i left it in to the dealership and they could find no fault, that was about a year ago now but it hasnt done it since!

Re: Whacky electrics and backfiring.
 

Well it's been run all week. 0630hrs blast over Pendle Hill each morning. Feels like a mountain goat. No glitches at all. I dare say it's been sorted.

Thanks guys, in particular Chakarist & Husky for the initial direction.

Bunka
:cool: