What do I check?

[mickwinf]

anyway the 550 tensioner is removed from the top so head needs removing anyway, if the chains need replacing it needs a complete strip down, its not a bad job to do if you are careful.

[Bitsa (Ralph Wright - RIP)]

Agreed I would strip the lot wether it needed it or not.After you know all is ok
Cheers
Bitsa

[JustcallmeMrT]

Agreed I would strip the lot wether it needed it or not.After you know all is ok
Cheers
Bitsa

Except for the screwups I'll make myself!  Downloaded and printed the honda shop manual and have my Haynes, so I'm ready for the weekend!

[Johnwebley]

before you attempt to take the head ,rocker cover.clutch cover ,in fact just about all of the motor,

 spray well with penetrating oil,concentrate on all the screws,bolts and nuts,

go and read the manuals for at least 12 hrs,

then come back and spray everything again,

preparation will make the job easier,
BTW,do you have an Impact screwdriver? much needed on Honda motors

[Bitsa (Ralph Wright - RIP)]

Mr T
The beauty off all the fours is when you strip them and knowing the price of gaskets etc is when you put that top bit on you know its sound.
You know the the cam chain is new the cylinders are as best you can do the cases and all the oil ways are clean and free off shite.All the blades are new and work, can go on about it for hours
But you albiet its not new you know it is.Never trust anything unless you have done it yourself
Cheers
Bitsa

[JustcallmeMrT]

before you attempt to take the head ,rocker cover.clutch cover ,in fact just about all of the motor,

 spray well with penetrating oil,concentrate on all the screws,bolts and nuts,

go and read the manuals for at least 12 hrs,

then come back and spray everything again,

preparation will make the job easier,
BTW,do you have an Impact screwdriver? much needed on Honda motors

I've started on the reading already.  I've got a can of WD40 at the ready and already have an impact screwdriver.  I'll have to borrow or buy a torque wrench though.

[JustcallmeMrT]

Mr T
The beauty off all the fours is when you strip them and knowing the price of gaskets etc is when you put that top bit on you know its sound.
You know the the cam chain is new the cylinders are as best you can do the cases and all the oil ways are clean and free off shite.All the blades are new and work, can go on about it for hours
But you albiet its not new you know it is.Never trust anything unless you have done it yourself
Cheers
Bitsa

True enough Bitsa, just wish I was a bit more confident about the job, but I guess there's a first for everyone.

[JustcallmeMrT]

Just looked at a replacement DID cam chain, and they're split link.  If that's the case, can't I cut the one that's on there and use it to pull the new one through, avoiding the need to pull the crank?

[mike the bike]

Forgot to mention,  make sure the tensioner is completely free (not sticking) and likewise for the pushrod otherwise you're wasting your time.

[Trigger]

I was referring to the snobs of gasket goo interested sump; nothing to worry about.   The particles of alloy are a different matter.   It's more likely that the cam chain tensioner (the horseshoe part) is sticking causing the camchain to rub the sides of the camchain tunnel.

What horseshoe? There is no horseshoe on a 550.

[Norniron]

I was referring to the snobs of gasket goo interested sump; nothing to worry about.   The particles of alloy are a different matter.   It's more likely that the cam chain tensioner (the horseshoe part) is sticking causing the camchain to rub the sides of the camchain tunnel.

What horseshoe? There is no horseshoe on a 550.

Stop it trig,of course there is

[Trigger]

I was referring to the snobs of gasket goo interested sump; nothing to worry about.   The particles of alloy are a different matter.   It's more likely that the cam chain tensioner (the horseshoe part) is sticking causing the camchain to rub the sides of the camchain tunnel.

What horseshoe? There is no horseshoe on a 550.

Stop it trig,of course there is

On a 400 there is. It depends what you call a horseshoe ? On a 550 there is a blade and a tensioner

[Trigger]

http://www.cmsnl.com/honda-cb400f2-england_model14647/partslist/E01.html#results

Number 50 is a houseshoe

[LesterPiglet]

Just looked at a replacement DID cam chain, and they're split link.  If that's the case, can't I cut the one that's on there and use it to pull the new one through, avoiding the need to pull the crank?

I have done that thousands of miles ago.

[JustcallmeMrT]

No horseshoe on a 500/550.

If the head gasket is still sound I'd leave it alone, the tensioner can be removed by removing the skull cap/rocker train cap and removing the cam, the tensioner is held by a 6mm bolt at the back of the head, remove that and undo the 6mm nut from the adjuster screw and you should be able to push it forward and lift it out.

As Bryan says, the pistons won't come out of the bottom of the casing but you can split the rods off the crank to allow not only the primary but the camchain to be threaded off the crank. All you need to do is remove the primary shaft in order for the 2 casing halves to be split, assuming of course you've removed all the bolts/casings. The primary shaft can be removed by screwing the step bar bolt (lower engine hanger bolt) into the end of the shaft and using one of the footrests as a sort of sliding hammer. There is a thread somewhere showing pics of how to spot if the primary chain is buggered, look for it. Keep track of where everything came from, especially the conrods caps, they must go back onto the same rod they came off.

Sounds hard but actually a bit of common sense and it's fairly easy.

Ok, I actually think I can visualise all the parts you mentioned - sounds doable.  Will have a search round for how to tell if the cam chain and primary chain are worn and have a go this weekend.