Piston Orientation and Chain Tensioner Q's

[JohnnySomersett]

Can I have a quick bit of help please on the next stage of my CB250 rebuild:

Tonight I'll be installing the new pistons and jugs etc. What way around do the pistons face? should the diamond marker face the inlet or exhaust side?

and

The cam chain tensioner... I've read the manual and it almost makes sense, am I right in saying it goes like this: install into side of cylinders, release lock nut so it springs out, tighten lock bolts? Should this be done with pistons at TDC or other position?


Thanks in advance

 

[TheCoffeeGuy]

Not sure about the pistons.

You are right on the installation of the tensioner. I always put pressure on the kickstart, say half a crank so that the front, (the part of the chain on the other side of the pistons) is taught, then loosen the tensioner lock bolt and allow the spring to put pressure on the chain, hen snug up the bolt.

 

[hillsy]

Do the pistons have valve reliefs cut / cast into them? Orientation should be obvious if they do because the inlet valve is bigger than the exhaust.

Otherwise, usually the markings face to the front of the engine.

 

[JohnnySomersett]

Thanks guys, that answers that perfectly.