CB550 Bottom and top end rebuild

[Topcat]

Hi all,

Been a long long time since I checked in. Actually a fairly long time since I've had any time to work on the the 550. Thought I'd give you all a quick run through of what I've been up to, it's taken me so long to get round to this as I've had a bunch of other projects taking up time, including some building work that ended up causing problems (and a lot of time and money to fix).

However in the odd 5 or 10 mins I've had spare I've gone through the following on the cb550 engine.

Stripped down the engine back to cases and inspected all the internals.

Cleaned and rebuilt the bottom end and top end including replacing all bearings seals o rings, chains pistons etc


Where I am up to now is installed the rocker cover (freshly assembled new arms and shafts) to the head using the elastic band trick to hold the arms off the valve stems (don't really want to bend anything at this point).

At this point I'm just waiting on some new bolts for the rocker cover and need to source a L hand stamped plate and some soft washers that sit underneath. Does anyone have a plate and/or set of washers (think they are aluminium) they'd be willing to sell?

I can turn the motor over using the kick starter and can feel the pressure building up so once the cover is installed I'll do a compression check and leak down just to make sure everything is nice and sealed.

Finally my two big concerns at the moment is the cam chain tensioner seems not to have much in the way of free play in it. I'm assuming this is because the chain is brand new and will give a bit over time but can anyone confirm how much tension should there be on a brand new chain? (I've gone through the chain tensioning procedure where you move the 1-4 TDC then 15 degrees on (or where the spring attaches) before adjusting but it seems there is very little or no slack.

And finally the oil pump has a chunk out of the casing on the external side of where the o ring sits. I'm hoping this will still give a good seal under pressure but I may need to replace the pump if not.

Adding a few pics if it'll let me.

Topcat

[Bryanj]

New camchain is usually very tight so not much movement on tensioner, for soft washers use 6mm "Dowty" washers(alloy with rubber insert) but fit them carefully, as to the bracket i am afraid you will have to keep scouring ebay till one comes up, i actual have right hand but not left

[Nurse Julie]

Thats looking great.

If you give me the Part number of the  bracket i will look on my stock list for one .

[Trigger]

They are strange elastic bands holding up the rockers, they look more like the silicone 0'rings that seal the liners 

[Topcat]

They are strange elastic bands holding up the rockers, they look more like the silicone 0'rings that seal the liners 

Haha yeah they are some strange ones, only ones I had on hand but have since bought a big box of proper elastic bands for all future bike building uses

Topcat

[Nurse Julie]

They are strange elastic bands holding up the rockers, they look more like the silicone 0'rings that seal the liners 

Haha yeah they are some strange ones, only ones I had on hand but have since bought a big box of proper elastic bands for all future bike building uses

Topcat

I like them in green. Were they not meant to be fitted to the bottom of the liners before you fitted the barrels 🤔🤔🤔

[Bryanj]

Julie i think the left part number is 12336323000

[Topcat]

Thats looking great.

If you give me the Part number of the  bracket i will look on my stock list for one .

Hi Julie,

Sorry for not responding sooner had a bit of an annoying time with the bike (will explain later quite funny not its resolved though).

Part number is 12336323000

Thanks
Topcat

[Topcat]

So I buttoned up the the engine and decided to do valve clearances and compression check while I'm looking for the plate part.

So hooked up the solenoid battery and got the starter turning over. Got the compression checker out and to my dismay all four cylinders were running at 60psi  I really didn't understand this as looking at the cloud of oil and air coming out of exhaust side there was I was sure more pressure.

However I went back and checked all the clearances and tried again same result.

At this point I remembered my had given me a lot of his old tools so went searching and found another compression checker all four cylinders reading 160-170 psi.

So tomorrow I'll be burning the cheap sealey compression checker. But I've learnt a good lesson.

Topcat

[Erny]

Do you have carbs mounted? If so, you have to open them fully, incl choke to reach max psi

[Nurse Julie]

Thats looking great.

If you give me the Part number of the  bracket i will look on my stock list for one .

Hi Julie,

Sorry for not responding sooner had a bit of an annoying time with the bike (will explain later quite funny not its resolved though).

Part number is 12336323000

Thanks
Topcat

Hi Topcat, sorry, we have 3 of the right hand ones but none of the left side.

[Topcat]

Do you have carbs mounted? If so, you have to open them fully, incl choke to reach max psi

Nope no carbs at all, but as mentioned i think it was a dodgy compression gauge. I'm pretty happy with 165-170psi cold

[Topcat]

So I've been trying to run the engine on the starter and checking the oil pressure. Couple of quick questions

1. Is the starter generally enough to build up pressure to trigger the oil pressure switch? I've wired it up on a test light and it's not switching off and I'm nervous about running the starter any longer than I have at the moment.

2. What's the best way to check the oil is making it to the head?

Just want to be 100% sure before trying to fire up the engine properly.

Cheers
Topcat

[Nurse Julie]

Take a tappet cap off of each end and look for oil spray from the spray bars, when the engine is running.

[Topcat]

Take a tappet cap off of each end and look for oil spray from the spray bars, when the engine is running.

Does the engine need to be running or should the starter be able to get the oil to the rockers?

Cheers
Topcat