A old 93 k11.... it tests fine ie spins fast and free when it out the bike but when bolted in, it turns over but not as quick as I think it should plus after a few seconds the engine stops spinning. It's hooked up to a running car so not relying on the bikes battery. 

The bike has sat for around 12 years though, yes I've had the plugs out and put oil in and a general going over before trying to start it.

I know the starter might still probably be duff although it spins fast and free out the bike. 

Thanks for any help or advice..

Clean the ground connections under the tank and on the side of the transmission just above the shifter.  Get them nice and clean with shiny terminals.

You didn't mention how many miles, but anyway, it won't hurt to take the starter apart and clean the commutator and check the length of the brushes.  Worn brushes will not transmit enough current to spin the motor under load.

These are two jobs that should be done on any old brick, especially one that has been idle in unknown storage conditions for an extended time.

Thanks for the reply, I cleaned a few connections but not under the tank. The starter spins fast and free when off the bike but when back on off different.

It's only got 25000 on it

Not a lot happens here but at least you answered.

There maybe several reasons for starter to stop turning 
Primarily associated eith high current connections

What makes you think that energising the system by jumper leads is enough power to turn a 500 watt starter under load continually ?

I think you may find that the starter relay or brushes is your issue . Many have fused closed by the high currents required durring startup . Especially with a low capacity - poor state of battery.probably worth while getting somone who knows what they are doing to clean the contacts on the starter relay  to start with then look for the replacement brush set  , not expensive .

There many many posts in the forum relating to starter issues
There is a'portal page '  with a search box    try using it and researching your issue... eh ?

Good luck

Ian9 wrote:Not a lot happens here but at least you answered.

Here are the stats from the Portal to which charlie99 was referring you. Our users have posted a total of 199888 messages in 16144 subjects.


A '93 Brick with 100,000 miles on it today will be in far better condition than yours with only 25,000 miles of usage and 12 years of neglect. Bricks depend on efficient electrical conductivity; neglect leads to condensation and corrosion among the plugs, connectors and other devices. All connectors and terminala should be cleaned and inspected where possible, including the terminals of the relays in the relay box beneath the tank. All fuses should be replaced with new ones. If you follow the suggestions of charlie99 and Point-Seven-five and perform a thorough inspection of the electrical connections, you'll have a fair chance of restoring this Brick to function, after you thoroughly clean and inspect the fuel system.

View Troubleshooting the EFI in the Tech Pages accessed through the Portal.

At 25,000 miles I doubt the brushes in the starter are worn so I would suggest just opening the starter motor up and cleaning the commutator.  Clean all the electrical connections and get a good battery.  That should take care of the electrical system as far as starting. 

There are things you need to check in the fuel system.  Injectors, fuel tank, fuel filter and fuel pump.  Bricks that have been idle for long periods with old fuel in the tank will have a gooey black mess in the tank from the old fuel dissolving the rubber vibration damper that holds the fuel pump.  The fuel filter is also an item that should be changed as it can be clogged with the varnish from the old fuel.

You should also check the rubber parts of the vacuum and air induction systems for cracks.  The caps that cover the throttle body vacuum ports are also sources of air leaks that make idling difficult.

As Laitch mentioned, low mileage bricks are almost always in rougher shape than similar vintage, but high mileage, machines that are regularly used and usually require a bit more TLC to get running properly.  The good news is that the inmates here have the largest experience base you will find anywhere with the information to get your bike running.

Yes in the middle of cleaning things and see how it goes.

I will second all these comments, having bought various bricks over time.

The highest mileage one I got was the K100LT with about 91k miles. It got head bearings and a clutch cable.

The lowest mileage one I got had 29k miles, it sat 17 years in a boat shed, it needed everything rubber replaced, fuel system, brake lines, tyres, even the leaking fuel tank. I knew what to expect and it did everything expected so it was no shock to me. Even with diy and so one I spent more on it than I paid for it but it was on budget so I was happy. 

Next one was RT with 36k miles and it got head bearings, rear main seal, clutch and many other bits and pieces but over 50k miles so it did good.

Two weeks ago I got another K with 58k miles on it. I have put close to 1,000 miles on it since and enjoying it.

I think it's to much for me to take on