Well now I have really done it...

Szeigler

Active Member
SO I picked up this 1975 cb550f as my next project and now it is sitting in my garage. I am planning to build it up as original but with some of the cafe sensibility. the first task is going to be getting that lump unstuck. I believe the culprit is years of storage without being run.Possible covalent bonding between the steel rings and the aluminum cylinder. SONIC was kind enough to share the link to the repair manual for the bike. I have managed to get a key cut using the seat lock code which does operate everything accordingly. I have also picked up a battery and have been trickle charging it. My plan of attack is to check the electrics out with the exception of the starter using the battery so that I can define any needs there. Any advice is welcome. I am new to motorcycles, and while I am not overwhelmed yet, I do want to be successful with minimal frustration.

cheers,
SZ
 

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Looks like a fairly complete example, if a bit the worse for wear.


You are correct in your approach so far. DON"T disassemble just yet.
Take some time to figure out exactly what the current state of affairs is BEFORE you bag and tag it all.


Patience and organization is key. Once you start the disassembly, take LOTS of pictures.


Keep the pictures coming, and best of luck!
 
The cylinders aren't aluminum. They have steel linings, so if any water got in the cylinders, they may be rusted. There's plenty of threads on here about freeing up a stuck engine.
 
More good news... It shifts through all the gears. Of course clutch is engaged... That might be bad.


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I wouldn't do anything until you free up those cylinders, or figure on a top-end (at least) rebuild, and decide if that's worth it to you.
 
If you end up needing to rebuild the top end (and it sounds like you might want to) luckily the CB550 is an easy one to do. You can do the engine without removing it from the frame - I've done it 2x.

Also, there are really inexpensive kits for the 550. I've used these myself. Set of 4 pistons, wrist pins, rings, gasket for $150. These kits amount to about a 0.5mm over stock on the CB550 if I recall mine. They're intended for the CB500 but work perfectly well in the CB550.

The kits I bought had pistons stamped 'ART' who was the OEM manufacturer for Honda back in the day. So they are likely good quality. With luck the small ends of your rods are OK. Might just grab a set of used stock cylinders, a set of these pistons and do the top end. Just need a base gasket and some o-rings.

http://www.ebay.com/itm/NOS-Honda-CB-500-Engine-Rebuild-Big-Bore-Performance-Kit-MC-Supply-Company-/221365413978?pt=Motorcycles_Parts_Accessories&hash=item338a68285a&vxp=mtr
 
@ carnivorous chicken, that is the plan. I bought the bike as a project and got it pretty cheap so I am expecting to get greasy at some point.

@tim thanks for that link.


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Szeigler said:
Uh... Has anyone else aver had to cut a primary cover off?


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No?
Why would you have to ever cut a cover off? At worst you have to drill out the screws that hold it on.....
 
Actually I used one of those grabit bits. It was quite awesome and very effective. Cover is off, and why was the engine stuck? Why a rusty alternator. Cover off and engine spins freely, gonna need to clean up or maybe replace the alternator but maybe not need to rebuild this sucker. Thoughts?
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Are there any tricks to checking compression on these engines? Can the rings not seat correctly after a long period of sitting? A little perplexed as I have straight 30 psi across all of the cylinders. Am I missing something?
 
It takes about 5 kicks to get a good reading.
Your valves have to be adjusted properly and your cam timing has to be right.

But looking at the amount of rust in the alternator id say you're probably in for a rebuild as that's a lot of water and if its in the alternator cover its probably all over the crank too.
 
SONIC. said:
It takes about 5 kicks to get a good reading.
Your valves have to be adjusted properly and your cam timing has to be right.

But looking at the amount of rust in the alternator id say you're probably in for a rebuild as that's a lot of water and if its in the alternator cover its probably all over the crank too.

I was kind of thinking the same thing. I will plan on taking the engine out of the bike and go all the way to the bottom. Should I be concernd at all about the transmission, is there a way to know what I am dealing with in there without cracking it open?
 
Szeigler said:
I was kind of thinking the same thing. I will plan on taking the engine out of the bike and go all the way to the bottom. Should I be concernd at all about the transmission, is there a way to know what I am dealing with in there without cracking it open?

Not really. With that much rust... You should tear it all down. Full rebuild. Id bet the insides of the crank case are UGLY.
 
Yep, going by that water line on the stator, I bet you going to find some brown "wooly" bearings and shafts in there. ::)
 
Hmmm. Any votes for dropping the oil pan and seeing what is underneath before i tear it down?


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