Hello everyone. I've read previous posts about using diesel engine oil to free the starter motor clutch. The only actual product I've seen named on here and recommended is Shell Rotella but it doesn't appear to be available in the UK. Can anyone recommend another suitable oil please?
Thanks, Ralph.

At the risk of being verbally lanced, I suggest: add a quart of ATF to your crankcase and let 'er idle for about 10 minutes, giving it a goosing now and then in the interim. Drain oil, change filter, re-up with your preferred dinosaur renderings and that'll probably free it up. This is a great and safe way to clean the internals.

for the benefit of those who haven't got the virus yet, can you describe the manifestations of s s c p and what brings it on . I had the idea that it was something that occurred in cold climate areas where bikes were left sitting in unheated garages

Any quality Turbo Diesel engine oil ought to do 'the trick'.

Having had a K bike's sprag clutch in my hands and in the dozen-plus intricate pieces of the unit I can say that there is a likelihood that any sprag anywhere could 'gum up' over miles and time if infrequent oil changes are the choice made by the owner. It's at the top of the 'bell housing' and about the furthest away internally from all that fresh, cleaning, dino juice in the oil sump.

The other (and IMHO possibly better but more expensive) alternative is to fill up with flushing oil which is specifically designed to aggressively clean the crap out of engines. Take note of the 500 mile limit though.

TWB is very definately right. When I got LFB the sprag clutch wouldn't engage consistently and because it's an '83 bike, I assumed it was the early type. I stripped the engine only to find that the sprag clutch had already been replaced with the later type. As I have a full service history with my bike (should have looked for the replacement date!) it's a good bet the clutch gummed up sometime during the ten years when the bike only did 9000 miles.

Werewasi: you'll know when you've got it. The starter motor takes off like a demented turbine but the engine doesn't turn over. Sometimes just jabbing at the start button can shock free it off but the chances are you will need to strip the engine and clean the sprag clutch in the very near future afterwards.

Kyle10 wrote:At the risk of being verbally lanced, I suggest: add a quart of ATF to your crankcase and let 'er idle for about 10 minutes, giving it a goosing now and then in the interim. Drain oil, change filter, re-up with your preferred dinosaur renderings and that'll probably free it up. This is a great and safe way to clean the internals.

Or you can use a market flushing aditive. I do so every other oil change.
Best regards
JAP

WoodyAUK75 wrote:Also at the risk of being verbally lanced, I'll add my experience.
I have yet to find a scientific reason for this, and have no wish to argue about why it happened, but that was my experience.

There is a myth around here, If you go from synth to dino or viceversa the mixture woul become crud...to be safe use semi-synth
So on my cars I always use semi-synth or dino.
For the K only dino...
Just to feel safe
Best regards
JAP

Thanks for your help and suggestions everyone. My bike was parked up for the winter with fresh, fully synthetic oil in it and started up at least once per week until the other day when the clutch wouldn't engage. It is garaged but unheated and the weather has been cold lately.