Topic: 1980 CB650c Rest-o by a crabby "old-timer"

[Hush]

Yes yes yes you can remove the sump without disturbing anything else.
Drain oil from sump, undo all the wee size 10 bolts, there are quite afew (10 from memory) and some may be hidden under crud so if the pan wont budge scrap around in the little valleys for one you missed.
I have to resort to the BFH (big farken hammer) and a block of wood to gently tap the sump either way until the seal finally released the pan.
There is a rubber ring gasket runs around in a slot right around the sump pan, you'll see what I mean.
Just clean up the rubber ring as best you can and then coat it with grease before installing.
Once the sump is off, wiggle the upside down funnel thing right in the middle of the gearbox off, its held on by small rubber band things, this is the filter screen, remove that and give it a real good clean but be very gentle with the screen itself as its quite delicate.
I guess you will be doing the oil filter while you are down there or have you already done it?
"D" will love you for doing all this. .............Hush.

[MickeyX]

I took D out for a little spin today while Kit is at work. Once she's warm, she runs smooth as butter. All gears check out ok. (really Kit, I was just checking them for, um, er...  ) Zoooooom down the freeway we went. Ducked down behind the gages and dropped the throttle. Hot d@mn that pup can take off!  (I swear I didn't go over 45mph, really.  ) Dropped in with Kit's friend but he didn't have time to help with the light carb leak fix right then. Will take D back tonight after his buddy heads back to Utah. We need his warm, dry garage...

[Frankenkit]

75 is a funny sort of 45, there, hon.

[MickeyX]

It was 75 in sloooooow motion. 

[Hush]

See Kits, once you get her running you'll fall back in love with D.
These 650's haul ass when running true, my Custom gives me glimpses of her power just before I discover a new "must fix" situation, latest is new chain required GRRRRR.

[Frankenkit]

oh. WTF, I ordered those exhaust collars off ebay, specifically for cb 650, and this is what they look like
(sorry, pic got deleted.  Totally not the right collars, though.)

Is that what the cb collars look like? if so, then I had totally wrong collars on mine from the get-go...   the outer part is identical to what was on my bike (the finned ring) but these... totally different.  I'm a little confused here, but seeing as one can never trust the bike's history to have put the right stuff on my bike at any point in time, I'm not sure if I'm screwed or not...

[A Grove]

Those collars look identical to the ones on both my 550's... Not sure about the sixfiddy's tho.

[martino1972]

the 650 once look different,they have a thin skirt on the other  side of the edge...

[scunny]

yep, those are the same clamps off my 650 and every other Honda I've owned

[Hush]

Mine don't Marti, mine look just like Kits.

[Hush]

What do your old half moons look like compared to the ones you just bought Kits?
A photo would help about now.
The curled up end goes into the head of the motor, so thats crush gasket then curled end then finned collars that are what the studs go through to hold pipes on.
Hope that helps, now back to the shed to sort my "o" ring chain.

[A Grove]

Wait.. I thought it was the other way around, hush.  Don't the "curled" ends go AWAY from the motor, to provide a larger surface area for the finned collars to push against? Hence the cut in the collars as well?

[Hush]

  Oops my bad,  :-[sorry Kits long time since I fitted my new pipes, Grovey is right, the curled parts fit into the finned collars, the other end pushes on the flanged header pipes.
Too busy thinking about "O" ring chains, and hey if you hear that some old git got strangled by his bike chain in NZ it will be me OK, I'm not at all trusting of the way these things are attached!

[Frankenkit]

My old ones look like marti described, with a 1/2" (or about 1cm) thick part, then a little lip, then a thinner, sorta grooved part tack-welded to it.
...like these


but the inner part got mangled/pummeled/crushed beyond the point of really easily fitting around my pipes, so I got these new ones, which look totally different. Not sure if they're different on different models of cb650s, or what?  Martino and I have the '80s, Hush, I think you have a '79, right?

...but the exhaust and head are the same, right? so where's the difference?

[A Grove]

It looks to me like one collar just covers more surface area than the other (on the header, that is).  Maybe there is something I am missing beyond that.

[Frankenkit]

Marti knows what I'm talking about... the thinner upper piece on mine is actually a lot thinner than that... but it got crushed real bad, so they're prety much unusable.

[Hush]

Those collars are just plain wierd Kits, maybe they are for a DOHC and someone just slapped them on a SOHC?
You definately have the right ones now Kits.
Something new I learned today, I don't need to shop online for crush gaskets, SUPERCHEAP sells them at $2 a pop!
OK so now it's: Crush gasket in place in head (I use grease or gasket goo to hold them in while I pee around getting the pipes right) then pipes on and lightly reattach rear mufflers so they can swing back and forwards, finned collars onto header pipes, halfmoons onto headers with curled lip facing away from heads, all lined up and happy.....bolt up collars then adjust/tighten rears.
All good...........Kits goes for a ride on nice quiet bike.

[scunny]

I've never seen collars like that but then 79 is as new as my bikes get

[Frankenkit]

On bike bandit's parts fiche, the 650c and 650 have different pipe joints and collars, which is a little weird. Given that I have the standard pipes on my custom, I'm wondering if they just switched the pipes, but didn't change the collar and pipe joints?  I have no idea if the bike had bad exhaust leaks before I did all this or not (it would've helped to know...) but it was all gummed together with exhaust goo all over the pipe joints etc the first time I took it all apart, so I suppose that's a missing part of the story I can make an educated guess about. 

So, I'll use these collars with these pipe joints.  I got my crush washers at Z1 for $2, I think.  I'll have to see what the weather's like as far as whether or not I really want to do this project out in the carport, or wait until my mechanic's back in town so I can roll D up on the lift and have a nice warm garage to work in...   Did I mention there's a starbuck's next door to the shop?

[Hush]

You big softee!
When it comes to doing a job in comfort or doing it in freezing conditions I always go with comfort.
Even when things don't go quite how you'd like them to, if you're in a warm workshop with a steaming cup of Starbucks in your fist you will feel like soldiering on and completing the job.
The oposite is working in a freezing carport and throwing half the parts across the road when things go titsup!

Scunny, that is one mean avatar, don't tell me that's you whizzing around the track!

[Frankenkit]

looks like I'm doin' this job outside.  Mechanic said "Is it broke?" in regards to oil pressure/oil pan/oil screen, yada yada. 
I said "no..."
he said "What do I say about things that ain't broke?"
... "Don't fix them?"
"Right."

So it's seeping a little oil and a little more when hot, but it's not a *lot* so I might just *leave it* until something else happens where I would need to... I just don't want to risk cracking te oil pan, stripping one of those 10 little bolts, blah blah blah if I don't really have to.  and when I have to, I'll have my $5 rubber gasket waiting.  I think in the mean time I'm going to spray that down really well, clean it, then see where the oil is actually coming from. (should've done that already, but figured I'd kill multiple birds with one stone with that thing off)  it's not much, just a couple drops on the ground when I park her while she's hot, then the seepage stops as she cools.

Attaching my street shield and shiny new exhaust clamps today.  hopefully everything will be nice and quiet after.  Got some exhaust cee-ment to hold the crush washers in place while I go to town arranging this, that, and the other thing.  Hopefully everything seats nice this time.

[MickeyX]

So, how is the exhaust cee-ment pond coming along, Kit?

[Frankenkit]

WellEaarl, Ah dun poured mah pond an' furgot mah cee-ment!

I read on the can (in caps, and full orchestration) DO NOT RUN ENGINE UNTIL FULLY CURED.
This meant 1) it would have to cure. 2) I wouldn't be able to go for a ride this afternoon.

Clearly, this wasn't a viable option for the time being!

I used ...oh geez, who said that... Soos?  Hush?  someone's idea of using some grease to hold the gaskets snugly in place while I crushed those little washers down. 

So.  It all went really well, the grease worked like a charm, I got everything lined up (now having a better general idea about what this was all supposed to look like...)  I actually started by pulling out the crushed, mangled gasket, stuck the flanged head pipe right in there where it should go, put the little pipe joints on, the collar, then spun on the nuts to see what it would look like if, theoretically, I could crush a little crush washer clean into non-existence.  Given that, I pulled apart my mockup, put everything together, and tightened it into what I figured was a healthy parameter of crush-age. 

Fired the bike up and took her for a short spin.  Throttle felt a little funny, but it could have been just that I needed to burn through the gas that had been sitting in the carb bowls for a couple weeks.  I swear this ethanol stuff just doesn't last as long.

There was a lot of vibration I didn't think I'd noticed much around 3-5k rpms.  Not sure where that was coming from... wasnt horrible, and not as bad when the bike was moving.  Curious, but probably fine.

We had a great ride.

Oh, I got the windshield on, and that bike feels real sporty now... grr. that windshield has a great curve to it... very aerodynamic.

[Hush]

Glad the grease trick worked Kits, that vibration...you did remember to tighten the rears on the pipes eh?
I got a Harley screen for my Police bike, attaches to the handlebars and looks a bit loose to me so making small brackets from bottom of screen to the headlight ears to stabilise it.
Just found out my brother-in-law is rebuilding the exact same bike as yours, should I warn him what he is in for?

[Soos]

On that vibration....


I have one tat kept vibrating as well.
Mine was around 4-6k rpm's, then again at 8-9k.(harmonics?)

Took FOREVER to track it down, could have SWORE it was from the hanger the exhaust mounted to.

Turned out to simply be that I had only 2 bolts holding my liscense plate down.
Put 4 bolts on there, and vibration gone.
Almost works better to find it if you have someone rev the bike, while you go around the bike to pinpoint where it is coming from...
That is if the vibration will show itself while the bike is stationary anyways.


Good luck!


l8r