bike died

[buzza]

Just put my r65ls on club plates and took it for its first decent run in many years. Prior to this I had done about 30km with no problems. The bike has 20000km on the clock. I did about 90 km at speeds up to 80kmh and was very pleased with how well the bike ran,however, 2km from home I pulled up at a light and the motor died. It restarted and got me a short distance and died again. Had to push it home.
Its dosn't appear to be a fuel problem and I have spark at the plugs. I am not great at electrical problems so any advice as to where to start.

[Barry]

If you have fuel and spark the only thing missing is compression. Could the valve clearances have closed up ?

[MichaelSydney]

Have you dropped the float bowls off the carbs ? They simply un-clip and you may well find a little water at the bottom of each. Tip it out together with any sediment and try again. The first run after such a lazy life will stir up all sorts of fuel problems.

My R65 had also lead a sheltered life and had recurring problems until I removed the tank, hosed it out with water and let it dry on a hot day. Fitted a new filter too and not a cough since then.

[Bob_Roller]

What color is the spark at the spark plug ?
If the spark is not a bluish white color you may have a failing ignition coil .
If you still have the original OEM black and gray coil, check it for cracks around where the steel laminate core comes through the plastic coil case .
It's a known problematic part on these bikes .

[buzza]

Thanks for the response guy's. Had a good look at the coil and found a crack on the front end. Is this the probable problem and if so why so suddenly? What would this do to the spark at the plug?

[buzza]

I forgot the photo.

[Bob_Roller]

Usually you'll get a reddish / orange color spark with a failing coil .
The coil usually starts with problems in damp conditions .

[buzza]

Thanks Bob, the sparks are reddish / orange and appear rather weak. I'm beginning to think coil. Is there any simple test that won't be way above a very basic understanding of electrics.

[mrclubike]

If the coil is cracked i would just replace it and go from there
This is what everyone is using

[montmil]

Argh!  The dreaded Bosch Crack-O-Matic ignition coil. Dollars to Donuts, that's your problemo. Especially troublesome during damp weather.

It would also not hurt to replace the coil's plug leads and the sparkle plug caps.

My old coil off the '81 R65. Note the circular pattern of cracks on the end of the coil. Stopped the bike deader'n a wedge.



Replace it with the easy plug n' play Dyna Brown coil. Yes, it looks orange to me, too. When space permits, I usually put the install date on replacement parts. Looking at that date on the coil... Woah! Time flys.

[Bob_Roller]

To answer your question about checking the coil, you can do a resistance check of the primary and secondary circuits of the coil .
The primary circuit is the one that the wires from the bike electrical system wires plug into .
The secondary is the sockets where the spark plug leads plug into.
If you have a multimeter and know how to use it, it's a quick test .
Primary should have around 1.5 ohms, the secondary 11-13,000 ohms .

[buzza]

Hi All,
Good news. I replaced the coil and she fired first go. Thanks for all responses.