1991 XTZ660 just died on me?

[MarkShelley]

I had a lovely 200 mile round trip today and my Yamaha XTZ660 ran beautifully until I got to my village. I pulled up behind a coach whilst it turned right and the engine went down to tickover normally and then just died. I put it into neutral and the light came on correctly, but when I pressed the starter button nothing happened and the neutral light just dimmed. I pushed it home and connected the optimate and the red desulphate light came on. The battery seemed really warm to me, but having never removed one after a long run I don`t know if that is normal?
Any ideas what may have caused it?
I have removed the battery and connected it to the optimate to see what happens.
It is a sealed battery by the way.

[BlackDogZulu]

I have quite often had the red light on the Optimate when connecting up, on batteries that I know are good. Disconnecting and reconnecting usually fixes it, so don't take the red light as a disaster unless it's doing it all the time.

Batteries will get a bit warm after a long trip as they have been 'on charge' continuously, but I've never had one get what you might call 'hot'. Sounds like the battery may be u/s, taking it all together.

[MarkShelley]

Yes, I have experienced the red light thing before with the optimate. That was the first thing I done, unplug it then plug in again. Still red I am afraid

[BlackDogZulu]

Can't turn the starter, neutral light dims - sounds like a dead battery. How old is it?

[MarkShelley]

Don`t know the age of the battery as it was on the bike when I got it in February. I will buty a new battery then whip it along to my friendly local mechanic (Paul Nobbs Motorcycles in Sutton, near Ely, diamond geezer!) so he can check the rectifier. Hopefully that will be ok as they are nearly £60.

[BlackDogZulu]

Originally Posted by MarkShelley

Don`t know the age of the battery as it was on the bike when I got it in February. I will buty a new battery then whip it along to my friendly local mechanic (Paul Nobbs Motorcycles in Sutton, near Ely, diamond geezer!) so he can check the rectifier. Hopefully that will be ok as they are nearly £60.

A hot battery after a run suggests either overcharging (regulator) or a battery gone high-resistance (new battery). I'd replace the battery first - if it's of unknown age it could well be past it. Then check the charging voltage. New reg/rec is an easy fix. Ten minute job, literally.

[MarkShelley]

The battery was showing a green light on the optimate after a night on trickle charge. I popped it back on the bike but it would still not operate the starter. I called my mechanic and he recons that a battery can show as ok on the optimate because it is making 12v, but its `cranking power` may be shot (I am guessing the amp rating?).
Should have the new battery to try out tonight so fingers crossed.

[BlackDogZulu]

Yes, a battery can show 12v+ and still be useless. The only sure test is what they call a 'drop test' or 'load test', where a device is fixed over the terminals and draws a heavy current briefly, which shows how good the battery is at storing and delivering a big current quickly. If it fails that test, it is unlikely to be able to turn the starter over.

When you get the new battery installed, put a multimeter across it. If your readings are:

12.5v - 13v with ignition off
13v - 14v with engine idling
13.5v - 14.4v with engine at half max revs

then you have solved it. (All figures approximate.) If it's charging at more than 14.5v, then you need a new reg/rec as well, as it's overcharging and will boil your new battery dry in short order. If you don't have a multimeter, get one - they are incredibly useful! Set it to volts in the range 0-20 to do the above test.

[MarkShelley]

She fired up first touch with the new battery and she is booked in for an early mot on Saturday when they will check out the rectifier. I will be using my Trident until then.

[BlackDogZulu]

Good so far ...

[MarkShelley]

Had a but clenchingly bad tank slapper on the Trident on the A120 near Dunmow today. There was a lorry strap or something in the road which my front wheel clipped. I was doing about 85 and I was seriously considering baling out as the thing was heading towards the armco. Luckily it sorted itself out just in time. I don`t want another one of those in a hurry!

[bunker]

Originally Posted by MarkShelley

Had a but clenchingly bad tank slapper on the Trident on the A120 near Dunmow today. There was a lorry strap or something in the road which my front wheel clipped. I was doing about 85 and I was seriously considering baling out as the thing was heading towards the armco. Luckily it sorted itself out just in time. I don`t want another one of those in a hurry!

It could be worse - it could have been one of these:

YouTube - [Motorcycle Accident]TT-Tankslapper-19sec

oya!

[MarkShelley]

XTZ sailed through the mot no problem but the rectumfrier is kaput. It was giving over 16V!
I have left it there so they can do the tyres at the same time. More expense!

[BlackDogZulu]

Glad it's getting sorted. And my XT sailed through the MoT this morning too. Go me.

[wolfzero]

Originally Posted by bunker

It could be worse - it could have been one of these:

YouTube - [Motorcycle Accident]TT-Tankslapper-19sec

oya!

i was there. that was the bottom of bray hill in 1999 the vid does not do it justice it was horrific we all thought he was dead that earth bank he hit is actually a stone wall at 6 seconds the camera shows where he actually hit that black patch on the road is the soil his body knocked off the wall.
he broke a load of ribs, a leg, an arm and his collar bone.