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 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. 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

Trade it in.

remove the immobiliser and see how it goes.

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).

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

calling yc

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.

[yorkie_chris]

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.

[Stu]

Sounds like problem Joshmac has

Originally Posted by Stu

Sounds like problem Joshmac has

Similar, except my electrics all stay on.. 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