Started refurbisuing the bike and began by trying to fix the seized front brake calipers by renewing seals etc(she has been stood inside for eight years)...after much "non improvement" it eventuallyturned out to be the brake lever jamming NOT the calipers. (two days wasted) Then I turned my attention to the REAR leaking brake caliper...loads of visible oil on the floor. Same process of cleaning out and replacing seals renewing tubing and oil header tanks etc...turned out to be a leak from the rear hub. (another two days wasted) All this time the engine wasEngine was starting and running fine on jump leads. Bought a new battery and for good measure repaced the Earth cable. Proud of myself till I realised I'd momentarily had the jump leads on in reverse order. Now she starts but the ignition light stays on. It will probably turn out to be something like another Earh somewhere but definitely NOT the voltage regulator which is where I'm starting today. I thought it might just be a bit easier than this!Oh yes...and now the radiator has started to leak...

What happens if you rev it? If you start and just tick over the ignition light will stay on. Give it a blip to 2000rpm and it should go out.

If it doesn't work the fact that you have the bike running means all is good but that possibly the regulator is kaput/fried. You can unscrew that from the back of the alternator, its an easy access. How are you sure that's not the problem?

Radiator = Radweld. Got to be the cheapest first try...

How am I sure that it wont be the regulator....really its just because NOTHING I diagnose is what I thought it was going to be! However, my spirit is higher today so tomorrow I try to fix the alternator by first checking the output with my voltmeter. (i'm worried that when I turn on the ignition the lights flash on for a very brief time...is that normal?
The radiator I tried fixing since it seemed it was just a single cell leaking. I took out the core and then tried some plastic weld on it . That worked fine but then a new leak appeared. I fixed that too but then another one and then another. Finally got a second hand one for £40 from e-bay.and its ok. Pressure tested it by making a tester from an old cycle tyre...worked a treat.Im finding it hard as a newbie to get around the site so that I can read EVERYTHING about the alternator before asking more junior questions....If I have to replace it can it come out without removing the engine. I started this as a quick summer project but its going to be a lot longer than that I think! Is there a way of getting friendly with K bikers from my country (UK)?? I think I might have found a company that makes m/c screens and am hoping they will have an old pattern for my "Sprint" after-market fairing. Cross fingers!

The alternator is very easy to remove especially if no ABS on board but I get mine off either way.

You do need the Clymer manual and if you haven't got one I would recommend it.

Basically you will see the plastic cover on the right hand side with the slots in it and you can see the alternator through the slots. You do need the battery etc out of the way but if you have a long allen key you can get it out without removing the starter. There are three bolts, you can only see two but the third is in between the starter and the alternator. A long allen key will reach in to it because the three bolts are equally spaced. You may find the brushes are kaput but I would be doubly sure to check everything else first.

All lights come on when you turn on the ignition, that's normal. Are there any that don't?

But go back to the question on the charge light which isn't answered, it does NOT go out when you start the engine until you rev it. If you start the engine and just run it you will drain the battery.

Sorry I didn't directly answer the question. No...the light doesnt go off when I rev the engine. I was probably so pleased it ran at all that I didn't pay it enough attention....and I WAS jump starting it from my car. Only noticed when I tried to let her run for a bit to clear the oil in the pistons after fitting the new battery..It may be just my perception but I think TWO things happen
1) As the ignition switch goes past its first detente the front and rear lights flash on and then off again very quickly(like a lightning strike)
2) It feels to me like the starter motor kicks in too ferosiously
I know that could just be the new battery but it sounds wrong to me.
Really appreciate your time on this and I'll let you know tomorrow what the voltmeter says.
Its night time here so enjoy your evening...mine's over!

Is there any possibility the red warning light in the clocks is an led? Maybe also check the alternator wires are correctly reconnected.

I had a few Ks and I don't think any of them flash the front and rear lights when you hit the ignition. The parking light function is the furthest setting back counter clockwise on mine. Then clockwise for ignition functions.

K1100 is different as it incorporates steering lock but the parking function is still fully counter clockwise.

Jumping with the wrong polarity can kill you regulator/alternator.

(Did it once to my MG in college when I had a wicked hangover. Had to put an extra car battery in the passenger seat with jumper cables attached to make it home without a functioning alternator.)

duck wrote:Jumping with the wrong polarity can kill you regulator/alternator.

(Did it once to my MG in college when I had a wicked hangover.    Had to put an extra car battery in the passenger seat with jumper cables attached to make it home without a functioning alternator.)

Back to post one and wrong polarity. Regulator can be removed without removing he alternator, it screws into the back of it. Easy fix.

You say the sidelights flash as you switch on. Switch to that position and leave it there, the parking lights will switch on.

Stumpy wrote:You say the sidelights flash as you switch on. Switch to that position and leave it there, the parking lights will switch on

I rechecked my 84 K100RT...yep from off it goes one stage clockwise t power up sidelights and you can remove the key at that position....all good.