XS650 top end torque specs

[peterg]

Input wanted!

In order to make my top end rebuild as fool proof as possible I’ve created a list of torque specs using the parts diagrams and lists as a basis. I obtained the numbers from manuals and this site. I didn’t bother with the head nuts and bolts specs.

Arrows point to components on the diagrams that are to be torqued.

The list shows all torque numbers in foot pounds. I’ve made notes re locklite, ant-sieze, etc. as well as stating “snug” for parts that don’t seem to have numbers associated with them. Parts that I couldn’t find information for are denoted with an *.

File attached

Any comments would be appreciated.

 

[Jim]

There's a standard torque chart in the factory manual. Use that for any value not called out by name.

 

[peterg]

Thanks Jim. I’ve used that chart but there are some bolts, like the ones that hold the oil strainer, that don’t use standard specs. The comments I’ve read on those bolts include statements like “don’t over-tighten them” and “don’t crush the mesh”.

 

[Jim]

but there are some bolts, like the ones that hold the oil strainer, that don’t use standard specs.

If it's a non-standard torque, the manual will call it out for special attention.

 

[Jim]

...The comments I’ve read on those bolts include statements like “don’t over-tighten them” and “don’t crush the mesh”.

Ahh... just reread that. Between the top and bottom plates of the sump screen are 3 metal tubes fixed between the plates. The bolts run through those tubes. To crush the mesh, you'd have to first crush those tubes. The 7 fl.lbs called for on a 6mm bolt ain't gonna do that. They'll be standard torque also.

 

[Jan_P]

Bolt and nuts is a science in itself and it depends on how the design intention is -- take for instance

In that design there is a O -ring 20
That performs the engineering tightening function stop leaking
Usually those are positioned in a grove with tight specification to shallow the ring will be crushed to deep it wont seal.
In this case the nut 23 has no sealing function
So what it needs to do is be strong enough to seat the O - ring
Depending on the surfaces surrounding the o -ring it wont matter how much you tighten the nut
or how large it is ..
Which people do as a mistake if the O -ring is broken
Assuming a gasket the first try would be to tighten some more and more and more
and at the end Get the threads in your hand

There are today places on Motorcycles where o -rings and gaskets are not used
Perhaps without chemicals.
It can be done if the mating surfaces are better machined
And the bolt tightening is done properly and with thinner designs also have a loosening pattern

So the factory manual specs is the rule Follow that and if that don't help .
Stop tightening in the more and more and more loop
Ending in big problems ( Done it myself ) . Look at the parts picture and look for a gasket or O - ring or some other
functionality and replace those instead of the tightening more and more and more loop.

On a side note there is a premium payed for Non Touched bikes / Cars that not an incompetent mechanic has over tightened every bolt.

Maybe not the right translation --> Unscrewed Vehicle