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Discussion Starter · #1 ·
Well here we go...some before pics!
As you can see it's not a stocker, tank is from a K1, signals/brake light are aftermarket, seat has been recovered (leather is fading already...anyone know if redyeing is worthwhile???) but she's all there and it decent shape. I have owned the bike for almost a decade. I traded it for a 1985 Toyota 4X4 (385 000 kms and rusty as hell) and a dozen or so hours in a tattoo chair. Over the years I learned how to turn wrenches in basement suite or under a tarp in the rain before I had a garage. She was a daily runner for 4 years or so. Rebuilt the front end, fork seals, boots etc..., replaced the swing arm bushings (not a millimeter of play in there now Bill ;) what a pain in the backside tho...) Replaced rings cuz I was burning oil along with cams, cam journels, lobes, valves, T-bars, etc were all done less than 1000 km's ago. I lined the tank and painted it along with the side covers, rebuilt the carbs and got about six weeks of riding in before the shifting issues arose...stuck in second gear. So now we'll break the cases and see what is going on with that tranny...
 

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Discussion Starter · #3 ·
Quick question about the numbers...the build date on the frame looks like 06/1973 and the engine is a #6xxxxxxx series so its a K6 right?

But the generator rotor is stamped K5...so what is it?
 

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Discussion Starter · #4 ·
OK so some damage discovered by that broken clutch basket fin thing (mentioned it in a different topic)...some small bits of metal found and minor scoring but still haven't found the broken fin. Also the intake cam was damaged by the PO...looks like someone had bad aim with the ball peen hammer trying to secure the cam chain link. Would that cause anyone major concern? A wobble in the cam perhaps due to the missing material? I remember this now from that first top end rebuild. Damn those cams were hard to find.

*EDIT* Should read exhaust cam...
 

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Discussion Starter · #5 ·
Found that the gear shift fork is cracked and slightly bent. Certainly this can't be helping things :(
 

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Discussion Starter · #6 ·
Cylinder barrels look good and come in at exactly 70.0 mm so I don't suppose boring will be necessary. Tough to photograph tho...

Pistons show some minor scoring on the outer walls and considerable carbon build up but rings are all good...as mentioned they are brand new.
 

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Discussion Starter · #7 ·
OK so this might put me in the running for a nice pink doughnut but....

Do I HAVE to remove the generator rotor from the crank in order to split the bottom cases? It seems that the upper crank should lift up and off leaving the crankshaft and transmission sitting in the lower halfs of their respective journals and Robert's your father's brother... ;)

I only ask because I do not have the special tool. :oops:

Also, what do you use to stop the crank from spinning in order to remove the 14mm bolt from the end of the rotor? My spark plug socket turned oil filter nut tool won't work... :?

When it comes time to split the cases do you just give 'em a good whack with a rubber mallet? Or is gentle prying in order?
 

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Discussion Starter · #8 ·
Any thoughts on the condition of the underside of the valves? Looks like a spark plug reading...dry and tan colored vs. sooty and oily.
 

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Wow, too bad about that cam - I'd be very concerned about that.

You'll have to replace that shift shaft, for sure.

The VIN says it's a K6, don't worry about the alternator, it's the same part # for all of them.
You do not have to remove the alternator rotor to split the cases. But if you want to, stick a penny between the gear on the other end of the crank and the clutch basket gear, you'll be able to get the alternator bolt out.
A rubber mallet is your Good Buddy when splitting the cases.

The cylinders do look glazed and should get a good hone job.

As for the valves, they can be cleaned, but need to be checked for leakage - put the head on the bench with both exhaust ports pointing straight up. You'll need to prop it, as the 450 head is pretty unstable on the bench.
Then pour some acetone into the exhaust ports and look in the combustion "dome" and look for leaking around the valves.
Then do the same for the intake ports.
If you see any leaking at all, get a valve job at a reputable shop. Don't think they'll get by, because they won't.
 

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You know, I just noticed that you do not have a chain oiler on your countershaft (best I can tell from the photo).
I'm working on Chris Garret's K6 right now, and it doesn't have a chain oiler either.

Either they've both been changed out, or Honda slipped a curve ball by me - I was definitely under the impression that ALL disk brake 450's (K3 and up) had chain oilers.......

Anyway, I'm packing now, leaving first thing in the morning. I'll try to keep up with this thread this week, good luck........
 

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when you split the cases turn it upside down and remove the bottom, then the gear clusters and the shifter drum stay with the upper case making sure you get all the case bolts out first lol
 

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GBones said:
Also, what do you use to stop the crank from spinning in order to remove the 14mm bolt from the end of the rotor?
You can also use a car oil filter wrench tool ( I dunno its propper name) , worked for me. Good luck with the scary bits (i.e. bottom end) :)

Lee
 

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Discussion Starter · #13 ·
Can you smell the fear??? :lol:
I must admit I am afraid...perhaps a night light will help? :roll:
 

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Discussion Starter · #14 ·
You know Bill...until I joined the forum I didn't even know what a chain oiler was... :? :oops:
Best I can tell this motor is not fitted with one either. I would be looking for the copper screen behind a bolt with what almost looks like a small grease fitting??? If that's the case I'm going to say that's one problem I won't have to worry about.
 

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Discussion Starter · #15 ·
Got the cases split, but other than a few damaged teeth on the kicker gear and a nick on the end of the shift fork drum...no more damage to report. I don't know if this would be an issue? (Look to the end of the small black arrow. First picture.)

As the shift shaft fork engages on the two tabs behind the end plate of the shifter drum I can't see the minor damage being a problem...I have been known to be wrong before mind you.

Otherwise the cases, transmission gears and main crank all come out looking in surprisingly good shape. :)

I guess the bent/cracked fork on the shifter spindle was probably my only real issue (in terms of being unable to shift gears)
 

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Garry... The larger detent wheel looks too "excentric" in your pic.... This can cause difficult shifting.... It has a larger hole than its "axle", but the hole must be round. If it is ovalled, it will "stick"..... I would also "dress" the "nick" down with a file to allow smooth motion of the smaller detent wheel across it.... (if the nick catches on it, it can cause shift difficulties as well......(less likely, but....) .......Steve
 

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Yep....That's it!.... the edges of the hole inside it must be smooth and rounded....Any ovalling "hangs" it up......It has to "roll" smoothly over those pins or it will wear groves in them (the pins) causing further shifting problems..... Look and watch closely as you remove the detents.....those springs are surprisingly "heavy"......
 

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Discussion Starter · #20 ·
Thanks Steve! I appreciate your insight...I have another set of bottom cases w/ shifter drum forks and neutral stopper assembly still intact. I wonder if the wheels are in 'rounder' shape!

Otherwise, I have been forewarned by numerous others as well about the reassembly of the shifter springs... :shock: :cry:
 
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