Topic: -82 CB650 identify lost crankshaft bearing?

[ThePwninator]

Hello!

I just got my engine back from vapor blasting. I decided to leave the crankshaft bearings in place which has now come back to bite me a bit since one of them seems to have gone missing while the parts where in the shop 

My question is
a. Is there any easy way to identify what used to be there?
b. Looking at CMSNL.com and some other places ANY CB650 crankshaft bearings seems to be really hard to come by. Is there any alternatives out there from other model that would fit a -82 CB650 RC03?

Thanks

[fizzlebottom]

There are no separate camshaft bearings in this engine. They're "built in" to the cylinder head and cylinder head cover.

And for the crankshaft bearings, good luck. Nowhere have I found a truly reliable source. David Silver Spares, CMSNL, and eBay have a few, but even worse there are 4 different sizes according to which your crankshaft needs: yellow, green, brown, & black. Brown and black are used by some CB550 models, but green and yellow are only CB650.

[ThePwninator]

There are no separate camshaft bearings in this engine. They're "built in" to the cylinder head and cylinder head cover.

Oops typo from me. Should be crank there as well

And for the crankshaft bearings, good luck. Nowhere have I found a truly reliable source. David Silver Spares, CMSNL, and eBay have a few, but even worse there are 4 different sizes according to which your crankshaft needs: yellow, green, brown, & black. Brown and black are used by some CB550 models, but green and yellow are only CB650.

So the 550's is the right size? Guess i can always do a summer below 5000rpm's and hope for the best with blacks... 😁

[fizzlebottom]

Oh man, I lied. I had the wrong tabs open. None of the crankshaft bearings for the CB650 were used on the 550. They're all CB650-only parts.

[robvangulik]

Did you ask the vaporblaster if he found it?

[ThePwninator]

Did you ask the vaporblaster if he found it?

He is on the highest of alerts

[ThePwninator]

Found this post that seems to suggest that the 550 bearings could potentially fit but not confirmed
http://forums.sohc4.net/index.php?topic=32228.0

[Flyin900]

The rear of the engine case is normally stamped with the letters that correspond to the bearing colours. Leaving the bearings in there for vapor honing is questionable. How do they look after the work, since the protective layer is pretty thin on those shells.

[ThePwninator]

The rear of the engine case is normally stamped with the letters that correspond to the bearing colours. Leaving the bearings in there for vapor honing is questionable. How do they look after the work, since the protective layer is pretty thin on those shells.

It's stamped BBBBB

Also, he only blasted the exterior of the cases 

[ThePwninator]

At this point I'm considering just doing a straight swap for all new 550 bearings, measure it out and see what i get...

[Little_Phil]

The rear of the engine case is normally stamped with the letters that correspond to the bearing colours.

The letters are surely same as 500/550 etc and are crankcase letters indicating the seat size of each main bearing. The ideal bearing color is selected from a chart dependent also on crankshaft journal dia.

[Flyin900]

It's stamped BBBBB

Also, he only blasted the exterior of the cases 
[/quote] 
That’s a good thing.

You need a B code bearing and at least all your shells are the same size on each journal. That corresponds to a brown shell bearing for that motor and David Silver spares has them for sale for $25 for one.

Your a lucky man.

[bryanj]

You need the pin size code off the crank to determine what shells you need as well as the cases

[ThePwninator]

The crank id is
12222 (A)

So should be (i think)
Green
Brown
Brown
Brown
Brown

I still haven't been able to find any Cb650 bearings but it seems as if the 550 should have the same diameter? Anyone that can confirm?

[bryanj]

If the part number is different it should not be used, the holes for oil feed may be in a different place or the tab different or even a groove.
Try putting the part number you want into google and see what happened, somebody already said Dave Silver had some.

[fizzlebottom]

The crank id is
12222 (A)

So should be (i think)
Green
Brown
Brown
Brown
Brown

I still haven't been able to find any Cb650 bearings but it seems as if the 550 should have the same diameter? Anyone that can confirm?

According to this, I think you need:

• Yellow
• Green
• Green
• Green
• Green

[bryanj]

No mate, if the case is a B its green or brown according to that table

[Flyin900]

David Silver has the bearings if you care to look there. He has a US based operation along with the British original shop. They are the correct CB 650 shells.

[fizzlebottom]

No mate, if the case is a B its green or brown according to that table

Ah yeah, I didn't see that response above with the actual case ID. Just saw the crank #s. Good call

[ThePwninator]

If the part number is different it should not be used, the holes for oil feed may be in a different place or the tab different or even a groove.
Try putting the part number you want into google and see what happened, somebody already said Dave Silver had some.

The original part has been discontinued. That's the problem
Can't find any at David Silver (or anywhere else for that matter)
Hence why I'm asking about the 550 bearings

[fizzlebottom]

I think you already mentioned the CB550 bearings. I did read a thread or two earlier on the HondaCB650 forums where someone took measurements and found that they share the same width as CB650 crank bearings. The problem is that there is no definitive answer regarding how they worked out in the end.

[Little_Phil]

Notice a normal glaring error in the CB650 table above. It won't affect you if you are just using the ident letters/numbers though.

Dim for crank journal dia for code 2 should read 32.980 - 32.990 not 32.880 - 32.990. Then dims same as CB550.

[bryanj]

Do you need brown or green? And if you have the part number please post

[Flyin900]

If the part number is different it should not be used, the holes for oil feed may be in a different place or the tab different or even a groove.
Try putting the part number you want into google and see what happened, somebody already said Dave Silver had some.

The original part has been discontinued. That's the problem
Can't find any at David Silver (or anywhere else for that matter)
Hence why I'm asking about the 550 bearings

I don’t know where your looking on the David Silver Spares site, as I can find stock for a 1982 CB 650 showing both brown and green shells available.

https://www.davidsilverspares.com/CB650SC-NIGHTHAWK-1982-USA/part_183091/

[ThePwninator]

I don’t know where your looking on the David Silver Spares site, as I can find stock for a 1982 CB 650 showing both brown and green shells available.
https://www.davidsilverspares.com/CB650SC-NIGHTHAWK-1982-USA/part_183091/

ah, It's the main bearings i need, not the big end bearing unfortunately

Do you need brown or green? And if you have the part number please post

The green is the one that has gone missing #13317426003