Another electrical issue

[Bibio]

sounds like the problem i had. traced it down to a furred up contact on the reg/rec connector (the one that comes off the reg/rec) and its a nightmare to get at. once fixed its been fine ever since.

[buckstone]

That's something I didn't do. Will have a look tonight.

On my way out this morning I tried to start it with the kill-switch at 'off'. It didn't start (unsurprisingly), but this time there wasn't a sound from the starter relay. I guess this proves the kill-switch is ok, so something else ruled out.

[Blapper]

Originally Posted by jagryan85

Sounds like the starter or solenoid is goosed especially as the lights dim when you press the starter button.

Try rocking the bike back and forth in gear it could well be the starter is jammed

Ryan

There are many causes for that, even hydraulic lock causes it.

[Blapper]

1/ have you tried bumping it (third time of asking) and 2/ are you charging the battery between attempts?

[buckstone]

Hi Blapper. Sorry - forgot to mention that I've not tried bumping it yet. I kind of thought it would be a waste of time, as there's a more fundamental issue there. I'll give it a go tonight though - will tell you more later.

[Biker Biggles]

Do you have access to jump leads and a car?If so try jump starting it off a known hefty source of 12 volts just to exclude a problem with your battery and its connections.If that doesnt work the next one is to take the current direct to the live terminal on the starter motor,thus bypassing the wiring /solonoid in between.You then narrow down exactly where the problem is.
Also as said above keep charging yur battery.Even new ones go flat very quickly if current is being used up with testing and attempts to start.

[SV650rules]

Could be starter relay moving contacts are burnt / oxidized and allowing some current through but not enough to turn engine over. Does relay get hot after trying to start this can indicate bad contact somewhere. Also starter motors can get tired with the carbon armature pickup brushes worn. The starter relay normally chatters if battery is low, it gets into a vicious circle of when it closes to pass current to starter the heavy current draw causes battery voltage to drop too low to hold relay closed, so relay drops out, when relay drops out the battery voltage recovers and relay pulls back in, now the contacts have 're-closed it draws current, battery voltage drops, relay drops out ........................ as long as starter button is pressed.

If you have a test meter you can hold it across battery terminals when you try to start bike and watch voltage, should maybe drop to around 9 volts, now try the meter across starter terminals direct, if voltage drops significantly more (below 6 volts) then power is getting lost between battery and starter due to bad contacts somewhere between battery and starter. (instead of a meter you can do this with a 12v bulb with a couple of wires soldered on and see how dim it goes, but results of 'how dim it went' are much more subjective than with a meter). Maplins normally sell some pretty cheap meters (around £10).

On most bikes the electrical circuit is designed to disconnect headlights when starter button is pressed to stop them drawing power from battery at same time as starter motor needs the power.

Your starter motor is linked to the engine via a sprag clutch https://en.wikipedia.org/wiki/Sprag_clutch - a marvelous and simple device - this allows the starter to turn the engine, but when the engine tries to drive the starter motor the device just freewheels - this replaces the more complicated and heavier solenoid assembly that is used on cars where an electrical solenoid actually pushes the starter gear into mesh with engine and when gear is fully pushed in some electrical contacts close and put power onto the started motor itself (older cars used the bendix starter where as soon as the starter turned the starter gear was 'thrown' into the teeth of the flywheel, these regularly used to fail due to the gear teeth being chewed up, as they were already turning when gears were bashed into each other - the new pre-engaged system is much more civilised) .

The sprag clutch can also be used in transmission as a 'slipper clutch' between engine and rear wheel on high powered bikes to stop engine braking locking up the back wheel.

[buckstone]

Don't have much time tonight, but stuck it in 2nd, rocked it back and forth, then tried to start it. Nothing.

Then I had a go at bump starting it. Still nothing.

Oh yes, and jump starting it from my car was similarly (un)successful.

I'm off to get a multi-meter tomorrow lunchtime, and I've got a free evening tomorrow, so will check out all the readings that everyone has suggested so far.

As ever, thanks for the advice. Fairly confident I'll have the cause identified very shortly.

[Blapper]

Did the motor turn over ok, and did you hit the starter button while the motor was turning?

[buckstone]

The engine hasn't turned over once since I got the new battery, whether by jumping, bumping or off the button.

I think there's a dodgy connection, faulty relay or switch somewhere. Hopefully the meter will help narrow it down. Maybe !!!