Author Topic: CB 500 Four (1972?) Full Restoration  (Read 140295 times)

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Offline calj737

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1125 on: April 12, 2017, 05:27:05 AM »
I was advised today to put a new gasket kit in it from the barrels up, which I think is a bit of an overkill, the head gasket is definitely leaking (advised to spray the new HG with a copper gasket compound). Also I think I may have the cam chain 1 tooth out!
Before you remove the head, remove the valve cover, release all head nuts in reverse order from torque sequence. Then re-torque them in proper sequence, stepping into the final torque by first pass at 12#, then a final torque value 15-16# as I recall. This will often solve a leaky head gasket after a rebuild.

You need not remove the tensioner to re-position the cam. If the #1 or #4 cylinder is at TDC per the points plate, the notch in the right end of the cam should be fairly parallel to the head deck. Simple as that.

A cam moved over a tooth will still "adjust" by the tensioner, so what gives with your situation that you believe the tensioner needs to be removed? Simply won't adjust?
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline MickB

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1126 on: April 12, 2017, 03:49:06 PM »
Cal
I knew you'd come to the rescue.
I'll give the head re-tension a go, the cam chain tensioner was dodgy when I put it back (I was trying to save some dosh, big mistake as the chain is rattling it head off), I'll try to get the adjustment to work.

The big oil issue is in the alternator case, that needs a good close look, I'm wondering if I can just loosen the case bolts a little and just crack the top case like a car hood and replace the oil seal on the crank? It maybe just the oil plug, I'm not sure yet where the oil is really coming from.

Offline AndyH

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1127 on: April 17, 2017, 05:10:11 PM »
Well I've just finished reading all 46 pages of your resto Mick, and have to say I'm mightily impressed mate!  8)
Having recently acquired a CB500 K1 cafe racer to restore, you're going to be a hard act to follow! ;D

Himble (Andy)
Perth
1971 CB750K1 (US import)
1972 CB500 Four K1 (SOLD)
Previously owned..
1967 Honda Sports 90
1971 Yamaha CT2 175
1973 Yamaha RD250
1975 Kawasaki KX125
1983 Yamaha XT250T
BMW R65
BMW R80
BMW R100LT

Offline MickB

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1128 on: April 17, 2017, 06:41:16 PM »
Himble thank you for your comments, but read SohRon's build, puts mine in the shade. After reading SohRon's build it made me go back and do a better job.

Offline AndyH

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1129 on: April 17, 2017, 07:05:09 PM »
It's all relative Mick!  SohRon's work is in the stars....mine will be somewhat earth based in comparison!! ;)
I blame it all on my close longtime friend who's a passionate restorer...he sucked me in!! :o
I should also say that I'm pretty impressed with the support you've received from members of SOHC4! ;D
« Last Edit: April 17, 2017, 07:08:23 PM by Himble »
1971 CB750K1 (US import)
1972 CB500 Four K1 (SOLD)
Previously owned..
1967 Honda Sports 90
1971 Yamaha CT2 175
1973 Yamaha RD250
1975 Kawasaki KX125
1983 Yamaha XT250T
BMW R65
BMW R80
BMW R100LT

Offline MickB

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1130 on: April 24, 2017, 01:25:26 AM »
The members were great and gave me motivation to get it done. The knowledge base is fantastic.
However after I missed out on BOTM I went into a downward funk, nearly slashed the wrists but slashed the tyres instead.


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Offline bryanj

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1131 on: April 25, 2017, 10:53:02 PM »
Best way to do the cam chain tension is loosen the locknut then hold pressure on the kickstart so the engine is nearly, but not quite, turning over so the front run of chain is tight and whilst holding the pressure nip up the lock nut.

You may have to repeat this a couple of times in different places.

N.B. NEVER UNDER ANY CIRCUMSTANCES try tensioning by putting a screwdriver in the end of the lock bolt !! This will normally, even if very careful, cause the tooth and worm gear to dislocate and never work again meaning head and barrel off the remove and repair/replace tensioner mechanism
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline MickB

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1132 on: April 27, 2017, 03:28:05 AM »
Thanks for the tip Bryan, you're a mate.


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Offline SohRon

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1133 on: December 09, 2017, 11:15:18 AM »
Mark - just wondering if you got your tensioner problem sorted. I've been away for a while and am thoroughly impressed with your progress. What a beautiful bike! Here's hoping everything is squared away and that you've just been too busy riding the bike to post!
"He slipped back down the alley with some roly-poly little bat-faced girl..."

Assembling my '74 CB550: http://forums.sohc4.net/index.php?topic=86697.0
Assembly of the Right-hand Switch (a rebuilder's guide):  http://forums.sohc4.net/index.php?topic=80532.0
Installing stock 4X4 exhaust: CB500-CB550 K: http://forums.sohc4.net/index.php?topic=82323.0
CB550 Assembly Manual: http://forums.sohc4.net/index.php/topic,151576.0.html

Offline MickB

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1134 on: December 10, 2017, 01:00:59 PM »
Hey SohRon long time..

No, when I built it I skimped on buying a new adjuster and only replaced the slipper on the adjuster, a bad decision as you can hear the chain clearly.

However, I bought a 2016 Indian Scout last year and with the new toy the old one was just sitting there so I sold the bike with 47 miles on the clock.

The new owner was happy to fix the cam chain and some other minor issues.

All the best for the new year to all the greasy SOHC blokes working on these classics.

Offline Stev-o

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1135 on: December 10, 2017, 02:02:47 PM »
Wow Mick, so disappointed to hear you sold that bike after all the sweat you put into it.

I have multiple bikes, I just rotate the riding schedule, they are all unique in their own way.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline MoMo

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Re: CB 500 Four (1972?) Full Restoration
« Reply #1136 on: December 10, 2017, 06:52:00 PM »
Hey SohRon long time..

No, when I built it I skimped on buying a new adjuster and only replaced the slipper on the adjuster, a bad decision as you can hear the chain clearly.

However, I bought a 2016 Indian Scout last year and with the new toy the old one was just sitting there so I sold the bike with 47 miles on the clock.

The new owner was happy to fix the cam chain and some other minor issues.

All the best for the new year to all the greasy SOHC blokes working on these classics.



Guess you really like the Scout.   I keep thinking of acquiring one, just wish the wheels weren't black...Larry