FJ 1200 for Russia

[Millietant]

I never mature y

Hi! Can I ask the obvious question: am I tensioning the main drive chain correctly?
The chain has stretched by about 40 mm in 10,000 km.
I put the bike on the center stand and made the stroke about 20 mm, as it should be according to the book (15-20 mm). But when I lowered the bike, the stroke decreased to about 10 mm, will this be enough?
Or do I need to loosen the chain so that under load the chain travel is about 20mm?

i never measure my chain slack on the Centre stand. I only do it either on a paddock stand, or upright with both wheels on the ground (and a helper sitting on it). If your chain only has 10mm of slack  when the bike is off the stand, it is too tight and will be shortening your chain life AND putting extra stress on the gearbox output shaft.

I tend to set mine to around 25mm, figuring slightly loose is better than too tight.

[Motofun]

When doing tech inspection on new rider's bikes at the track, the number one fault I find is a chain that is too tight.  All owner's manuals are wrong in my not-so-humble opinion.  When finishing a turn and getting on the throttle the bike will want to squat (this is good).  However, if the chain reaches the limit and goes tight then that's the end of your suspension travel.  The result is a loss of traction, spinning up the rear tire and the possibility(if you cut the throttle) of a high side crash.  I've never seen a chain jump the sprocket on a street /race bike.  It's happened on bicycles and dirt bikes but that's a different story.  There's no one-size-fits-all answer as it depends on many factors but your chain ought to be able to easily slap up against the bottom of the swing arm when the bike is sitting on the rear tire.

[Edouard]

Thanks for the advice! I ride enduro. My main bike is a '92 KDX. On my FJ I set the chain sag to about 20mm on a side stand with a small load, that should be enough.

[Pat Conlon]

When doing tech inspection on new rider's bikes at the track, the number one fault I find is a chain that is too tight.  All owner's manuals are wrong in my not-so-humble opinion.  When finishing a turn and getting on the throttle the bike will want to squat (this is good).  However, if the chain reaches the limit and goes tight then that's the end of your suspension travel.  The result is a loss of traction, spinning up the rear tire and the possibility(if you cut the throttle) of a high side crash.  I've never seen a chain jump the sprocket on a street /race bike.  It's happened on bicycles and dirt bikes but that's a different story.  There's no one-size-fits-all answer as it depends on many factors but your chain ought to be able to easily slap up against the bottom of the swing arm when the bike is sitting on the rear tire.

^^^ From your lips to God's ears.....IOW, a loose chain is a happy chain!