Engine Noisy, died and wont start

[pmchardy]

I have a sv650 S 2002 25K miles

Bike has been running fine. Took it for its MOT this morning and the bike passed

On the way home I began to feel some vibrations from the bike, just didnt feel quite as smooth. A couple miles later the bike began to sound tappety, Was not too bad when I was accelerating but got louder when I rolled off the power.

As I was listening to this, the tappety noise got louder, but bike still seemed to accelerate OK. Noise seemed to be more front cyclinder than rear.

Tappety noise got really loud,Then engine stuttered and just stopped. No strange noise just stopped.

Pulled to the side of the road and when I tried to start, the starter motor just clicked. Sounded as though battery was dead,


Oil level seems fine, changed about 500 miles ago. Checked last week


This all happened over about 4 or 5 miles.

Battery is new, less than 1 year ,1K miles.

Just got the bike hon=me on the back of a trailer.


So what do you think the problem may be?

I will start looking at the bike, no strange smells or fluid leaks



I will check battery voltage
I will check starter
I will turn engine over by hand
then check for loose stator magnets
then check the Cam Chain

Thoughts, sugestions please
Thanks
Peter

[Ruffy]

Hi Peter,

Were you riding with lights on?

Don't forget the regulator/rectifier. SVs are notorious for weak reg/recs - someone will always mention it even if just in jest, but I genuinely think it's plausible yours has failed and has not been charging the battery. (Reason I ask about lights is that they're relatively high power and will cause the battery to flat quite quickly and also to below the point where it can fire a spark, leading to very rough running and/or stopping. Seems to fit the symptoms you've described.)

Assuming you do find your battery if flat as you suspect, and the engine turns over by hand, then if you charge it up it should be enough to start the bike and run it for a bit, allowing you to check voltage output from the reg/rec: Measured at battery terminals, it should be 12-13V at tickover (depending on battery condition) and rise with revs until it flatlines at about 14.5V at around 5000rpm. Any other behaviour and I'd be looking to change the reg/rec.

[pmchardy]

Battery 12.5 v
Lights look bright
Pulled stator cover. All magnets look ok
More oil in there than I was expecting

Will continue tomorrow
Thanks

[Seeker]

I'd be tempted to drain the oil into a clean container and look for any "forbidden glitter" (a torch helps to see if a bearing has succumbed and left its deposits). If the oil looks good you can always put it back in.
Magnets were more of an SV1000 issue than a 650.
I'd also check the valve timing - maybe a loose cam chain has jumped a tooth. A charging system fault isn't going to make tappety noises.

[EssEllTwo]

I agree with Seeker, this sounds more mechanical than electrical. The starter could be just clicking because the motor has seized solid due to cam timing going out, hence the tappet noise and eventually piston and valves smashed into each other.

[Ruffy]

Originally Posted by pmchardy

Battery 12.5 v
Lights look bright

Suggests battery is OK, so my hypothesis was probably wrong, and it does steer one towards a mechanical problem, as others have said.

Originally Posted by Seeker

... A charging system fault isn't going to make tappety noises.

Yes, fair point (It's the one symptom I was struggling with).

Onto other possibilities: Could a cam chain tensioner have collapsed/disintegrated? I'm thinking the "tappety noise" was the cam chain slapping against the engine wall? It would also affect cam timing leading to rough running. Worst case scenario is the noise got worse as the cam chain broke apart and eventually locked the engine.

Peter, does the engine turn over by hand at all or is it locked solid? Perhaps it's worth taking the top cover off to have a look inside. (You mentioned sound seemed to be from front cylinder so I suggest start there. Also it's the easier of the two to get to - small mercies!)

[Biker Biggles]

Bare basics-----You hear nasty mechanical noises and carry on for a few miles while noise gets worse then it just stops and won't turn over. Likely engine is fubared which is not unheard of with these engines. I'd start looking out for a replacement complete engine which is often the cheapest fix.

[pmchardy]

So got a new battery and bike started up.
Battery is showing 14.5 v when engine is running
I suspect last battery was on its way out, but was just over a year old.

Any way. now the engine is running I have video with the sound. Definately comming from front cylunder.

please have a listen and thoughts please

https://www.youtube.com/shorts/ggNLNr9KgyU

[glang]

I would take the sparkplugs out and with a finger over the hole see if theres compression produced when spinning on the starter - I suspect the front cylinder wont

[redtrummy]

Similar noise that's coming from the field behind us! But that's coming from a tractor! It does sound horrible. Does the front plug colour look about right ? On an old Escort I had it had problems on one cylinder and that was due to a holed piston.The only way I found it was by whipping the head off and having a look. If the compression is down then you will have to take the head off anyway. This is said with tongue in cheek, I have never stripped down a OHC engine. I would run it at a minimum though, you do not know what extra damage you potentially doing and it is not going to get better without intervention