Starting Problem - Help Please

[bigpaul]

I am desperate for some mechanical advice please as I know virtually nothing...I have had my baby since new (02) and I remember reading somewhere that there are three main faults with a Twin. The fuel pump (which I needed to replace 12 months ago) The rectifier (which has yet to go - touch wood) and another which I cannot remember! The problem I have now is that once the engine cools down it will not start again, only if I bump start it. When I pull over after having ridden it, it starts straight away in fact once bumped from cold, if I turn it off it starts straight away????? The fella at the garage who fixes it for me (and it is booked in for Friday) initially thought it was a switch on the clutch and advised me to by pass it by pulling out two wires and connecting them with a piece of wire, which I did...still does not start. I felt it could be the side stand switch to which he believed this would never go as it was a complete sealed unit!!??? I have a Dat Tag alarm fitted and he now thinks that there is a problem with the immobiliser - surely if it was this my baby would not start when I bump her???? I've got a feeling it could be the starter motor but what do I know?

I'd be grateful for some help and guidance before I get ripped off!

Many thanks

Paul

[bigpaul]

Just remebered what the third fault was - the spring things at the end of the choke that people were recommending replacing with the springs out of biro pens and someone was going to buy a job lot of them!!!!

[Whealie]

and the sidestand cut off switch, which sounds more likely. It is possible to simply disconnect this.

[bigpaul]

Thanks for the reply I have WD'd the side stand switch to death - put it up down, up down...light comes on goes off...still nothing! He claims because it is a sealed unit it will not go. Daft question I know, how do I disconnect it?

[BobA]

If the sidestand light is going on & off, it is working OK.

Your fault decription is a bit vague, when you say it wont start.

Are you saying the starter doesn't turn over at all? OR that the starter DOES turn over and the engine doesn't fire?

If it is the former, I would be looking at the starter solenoid and the starter button. The solenoid is at the end of the big + cable from the battery. You need to check all the connections, and the master fuse under the connector on top of the solenoid. The connections are prone to getting green & gunky, and eventually fail.


Good Luck



Bob

[DunkerD]

The clutch switch and sidestand switch are not included in the starter circuit if you are in neutral. Does your neutral light come on and nice and bright..?
Check all electrical connections, disconnect plugs sockets and check condition. Pay particular attention to earth points.

Good luck.

[Xander]

If i read that right.. cold no start.. hot starts fine.. right?

If so it could be as simple as a weak battery..(not dead just not good anymore) how old is the battery? is it full (if not sealed)? An alarm will slowly drain it. If the Battery is old I would start there.. see what the draw on it is. when starting.. or even when not just sitting with ignition on.. The AT is a big engine with a pissy starter if the battery is not completely good it wont work.

[bigpaul]

Thanks for all your replies - When I say won't start I mean I hit the starter switch and nothing, engine does not turn nothing, as if I'm not even touching it. In terms of being the battery it is about 2 years old, when not running, the main lights nice and bright? When in neutral the green neutral light is big and bright as it always was!

Plot thickened today however. Last night after the first response to the post I WD'd the sidestand switch to death, still nothing -this morning, dead as a dodo so had to bump it to get to work. Now it is pi***** down up here at the mo (great British Summer weather) and when I arrived at work, I don't know why but I left the kill switch off (the button on the right h/s of the handle bars) After work, if it's coincidence of WDing the sidestand, the rain getting somewhere & making a connection, leaving a possible faulty kill switch in a different position or just fluke, but it started first time??? I'd love to know the mechanics of a bike but when it comes to finding a fault like this it must be as frustrating as having to bump it of a morning??? No one has mentioned what the fella who sevices my bike thinks it is and the Data Tag immobiliser - Can it be this or is it looking like something else????

Thanks again!

Paul

[BobA]

Paul

Could possibly be many things you have mentioned.

Personally I rarely use the kill switch, so it could be that your kill switch has dirty contacts maybe.

As mentioned earlier in the thread, I don't think it could be the sidestand switch, because you can start the bike with the side stand up or down, UNLESS it is in gear (i.e the neutral light is not on).

It could be what I mentioned about the solenoid, the thick cables attached to it, the starter motor, or to the frame, or the master fuse connector.

It could also possibly be the immobiliser, as I have known some brands of these do immobilise the bike if the immobiliser fuse pops or has a bad connection.

A good mechanic should be able to find this in a couple of hours if you cannot do it yourself.



Bob

[markh]

I vaguely recall something about a diode pack connected into a 'starter interlock circuit' or something like that. Try searching for 'diode' on here, as I think it's been discussed. I'll go and have a look in the Haynes manual to see if I can jog my memory a bit better...

[a short time later...]

Okay, apparently there are three diodes in this circuit - one for the clutch switch, one for the sidestand switch and one for the neutral switch. I guess if either is faulty it would disable the starter.