Author Topic: Short Cut?  (Read 2101 times)

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Offline Phoenix

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Short Cut?
« on: May 16, 2018, 09:00:41 am »
If I warm up the engine, is there anything wrong with adjusting the cam chain by ear?
Ed Spengeman
Indy
1971 CB750K1 (Stock)
1973 CB350 Twin  (Gone)

Offline flybox1

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Re: Short Cut?
« Reply #1 on: May 16, 2018, 09:05:19 am »
Dont forget heat expands stuff...

If your cam chain plunger has been pulled, cleaned, and slides easily, do the adjustment on a cold engine and forget it.
If you are trying to quiet your engine, no need to spend time here.  Set it and forget it.
Spend your time on valves, timing and carb vacuum sync...
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
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"Knowledge without mileage equals bullsh!t" - Henry Rollins

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Offline ekpent

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Re: Short Cut?
« Reply #2 on: May 16, 2018, 05:20:05 pm »
 If its for a K1 the adjuster is just a spring loaded device and won't set anything. Be best to follow the instructions in the book.

Offline Phoenix

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Re: Short Cut?
« Reply #3 on: May 16, 2018, 08:34:54 pm »
What I mean is I loosen the shaft then push it in until I get the least noise while the engine is running.
Ed Spengeman
Indy
1971 CB750K1 (Stock)
1973 CB350 Twin  (Gone)

Offline scottly

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Re: Short Cut?
« Reply #4 on: May 16, 2018, 09:16:51 pm »
Do it by the book.
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline PeWe

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Short Cut?
« Reply #5 on: May 16, 2018, 11:31:06 pm »
First time I followed the thin Honda manual/users guide I got with the bike. That did not work. To adjust when idling. Better when engine is not running.

Not properly adjusted ignition cause chain rattle.
« Last Edit: May 17, 2018, 12:27:48 am by PeWe »
CB750 K6-76 1005cc JMR Billet block.
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline pjlogue

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Re: Short Cut?
« Reply #6 on: May 17, 2018, 01:25:42 am »
15 deg. PTDC, bike cold, engine off is the only way I know that works.  Doing it while engine is running will leave you with way too much slack in the chain and an engine that sounds like a cheap sewing machine.  If I remember correctly, the '76 owners manual was wrong.  They left out the 15 deg. PTDC part.   

-P.

Offline Don R

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Re: Short Cut?
« Reply #7 on: May 17, 2018, 01:28:03 am »
 Remove the adjuster and check to see if the shaft is dinged by the pinch bolt and stuck. You might need a gasket.
No matter how many times you paint over a shadow, it's still there.
If you love it, set it free, if it stays it's probably one of my 750's.
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Offline madmtnmotors

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Re: Short Cut?
« Reply #8 on: May 17, 2018, 04:19:49 am »
Engine off to adjust timing chain. The best way to quell the rattles is a good carb sync. ;)
« Last Edit: May 17, 2018, 09:08:37 am by madmtnmotors »
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                                           http://forums.sohc4.net/index.php/topic,139544.msg1579364.html#msg1579364
                                           http://oldmanhonda.com/MC/wiring750K1.html
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Follow up on your damn posts: http://forums.sohc4.net/index.php/topic,144305.msg1791605.html#msg1791605
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Offline flybox1

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Re: Short Cut?
« Reply #9 on: May 17, 2018, 06:37:13 am »
What I mean is I loosen the shaft then push it in until I get the least noise while the engine is running.
Yes, we understood you, but the cam chain adjustment wont get all the noise out.
re-read what I posted.

Dont forget heat expands stuff...

If your cam chain plunger has been pulled, cleaned, and slides easily, do the adjustment on a cold engine and forget it.
If you are trying to quiet your engine, no need to spend time here.  Set it (by the book) and forget it.
Spend your time on valves, timing and carb vacuum sync...
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline pjlogue

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Re: Short Cut?
« Reply #10 on: May 17, 2018, 07:34:19 am »
What Madmtnmotors said is good advice.  A out of sync. carb will make the motor sound real clackity and the sound mimics the sound of a lose timing chain.

-P.