Topic: What's a Good '72 CB500/4 Pry Point??

[Dr. Frankenstein]

I'm digging into my 500/4 engine, have all the bolts taken out, but can't find a good pry point - the cases are of course stuck together with the Cement of Ages, and I've tried loosening it up with a rubber mallet, but No Joy so far...anybody have a pic of what and where...?

(One hour later...)

Still No Joy - I've tried heating the seam, a dead-blow hammer, crowbar, rubber mallet and all of the above; this sucker is tighter than a clam at low tide...

[Don R]

 In my experience, there's always one more bolt.

[Dr. Frankenstein]

And you would be CORRECT, Sir...! There was another one stuck WAAAY down deep in front of the oil pan...so I got that out, the cases have split, but it seems like there's something else keeping them from coming apart - rusty dowel pins, maybe?  Or does the rotor need to come off too? It looks like I can just lift it out with the crank, after I get the cases apart - the engine is sitting upright on the bench, btw...is it easier to separate them by turning it over?

[Don R]

 I'm not a 500 guy but check the sides of the motor for shifter parts, bearing retainers and such. The dowels can bind if the case tries to open unevenly.

[Dr. Frankenstein]

Everything seems to be clear, but it's like it's stuck or something is preventing the top from lifting off. It does still have the rotor on the crank, but that's in a bearing and the top should just lift off - I keep thinking rusty dowel/oil passage...rocking it back and forth gently seems to have no effect...

[bryanj]

The "top" does not lift off, turn the cases upside down then remove the primary shaft(bearing retainer plate behind clutch off, remove oil pump and use soft drift on shaft from oil pump end) then lift lower case off.
ALWAYS build in top half to make sure all bearing dowels are located, replace primary chain as when worn it chews into oil gallery and replace damper rubbers in primary cush drive.
Chain use Kawasaki part, number mentioned on here many times

[Dr. Frankenstein]

There's no room to put a drift in there...I DID however find this thread using the rear engine mount bolt that I think will solve my problem - my set-up is just like Ryan550K's:
http://forums.sohc4.net/index.php?topic=42910.0

[Oddjob]

I use one of the front footrests as a slide weight, position it so the rubber part faces outward and use that as the grab handle. Comes out pretty easy doing that.

[bryanj]

Sorry but yes there is, i have done it many times and have a piece of bronze in my toolbox just for that job

[Dr. Frankenstein]

Where do you put the drift, on the bearing or on the gear...?

[Oddjob]

On the gear as the gear is on the end of the primary shaft. However using the slide weight is the better option, far less chance of any damage.

[HondaMan]

You must pull out the primary shaft before the cases can open up. It's the one with the little gear on it, toward the front right next to the clutch.

[Oddjob]

Sorry Mark but that's incorrect, the primary shaft can stay in place as it stays in the bottom case, so the top can be removed no problem. Plenty of images of it in the bottom case in the workshop manual. You maybe confusing it with another engine but AFAIK this was about the 500/550 engine.

[bryanj]

Problem is Ken all the bearing pegs and half clips are in thevtop half

[Dr. Frankenstein]

I got it - once I got that hidden bolt out of the way it came right apart. I wound up using the engine bolt and a big socket to get the primary shaft out to; popped right out.

[Oddjob]

Problem is Ken all the bearing pegs and half clips are in thevtop half

I didn't say build it back up in the bottom half, it was me 14 years ago telling people to build them back up in the top case upside down, before that they followed the manual and built them in the bottom case, which caused all the gearbox pegs being pushed into the top case when they bearing moved. The point was, the cases can come apart with the primary shaft still in situ.

[HondaMan]

Problem is Ken all the bearing pegs and half clips are in thevtop half

I didn't say build it back up in the bottom half, it was me 14 years ago telling people to build them back up in the top case upside down, before that they followed the manual and built them in the bottom case, which caused all the gearbox pegs being pushed into the top case when they bearing moved. The point was, the cases can come apart with the primary shaft still in situ.

I don't think I understand this, maybe it's regarding some terms? The one I'm calling the 'primary shaft' is the one (number 1 in this image) that holds the gear for the primary chain and reaches into the oil pump on the left side and the clutch's primary gear on the right side: it has to come out to let the top half of the cases come off.

[Oddjob]

Sorry Mark but you must be confusing it with another engine, the 500/550 cases can come apart with the primary shaft still in place, it’s completely in the bottom case, lots of pics in the manual showing the shaft still in place with the cases apart if you doubt me.

[Little_Phil]

See above. It's all about whether you invert the engine and remove the lower case. Or leave it up the normal way and remove the upper case (in which the guts all sit in the lower case)

[Oddjob]

I should add that if you are trying to access the inside of the engine BUT are leaving the head and barrels on then you will need to remove the primary shaft first.

[HondaMan]

I should add that if you are trying to access the inside of the engine BUT are leaving the head and barrels on then you will need to remove the primary shaft first.

This is what I am thinking about, having just done it recently.
I think what's missing here is: was the top end removed first? If so, then the cases will separate, leaving the crankcase in the bottom half. If not, the crankcase is still attached to the top end and the primary shaft has to come out to separate the bottom cases.
I guess I'm missing part of this teardown narrative?

[Oddjob]

The poster didn't actually say, all that was said was he couldn't get the cases apart.

I assumed he already had the head/barrels off as TBH there isn't that much in the bottom half you can change without taking off the head/barrels, like camchain for instance. Primary chain can be done BUT requires rods splitting from crank.

I think you assumed he was leaving the head/barrels on and so yes you'd need to remove the primary shaft.

Just a case of one person assuming one thing and another assuming something else. No harm done, at least we covered both ways.