Author Topic: CB750 K series cylinder head removal  (Read 714 times)

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Offline johndunbardean

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CB750 K series cylinder head removal
« on: May 22, 2021, 12:56:47 PM »
Hi,
I am obviously new to this forum. I have read lots of internet posts concerning the removal of the cylinder head of a cb750, most of which are brutal involving driving wedges, hitting various parts of the casting - even dropping the head/block on various media. Most of these methods guarantee to damage the quite delicate castings and/or mating faces. I have devised a simple tool to separate the head from the cylinders gradually and safely. Would this be of use to anybody or has this issue been solved a long time ago ?

best

John

Offline MD

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Re: CB750 K series cylinder head removal
« Reply #1 on: May 22, 2021, 05:33:28 PM »
Welcome from NE MN,

-MD
1975 CB550F Super Sport;  Lake Superior Circle 1000, 45-90 Saddle 1000, All in Yooper 1000 and SS 2000 in 48 hrs:  1985 GL1200A, MN in State SS1K

Offline 754

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Re: CB750 K series cylinder head removal
« Reply #2 on: May 23, 2021, 12:24:59 PM »
I dont find it a problem. ... usually a block of wood padded, hit with a soft hammer.. mainly in line with fins will knock it loose.
 If that fails  ( dont recall it happening (there are a few other options.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline madmtnmotors

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Re: CB750 K series cylinder head removal
« Reply #3 on: May 23, 2021, 12:43:56 PM »
There are two solid pry points, one above the 1/2 intake and the other above the 3/4 intake. I discovered these when removing a head that someone saw fit to apply some sort of industrial adhesive to BOTH SIDES of the head gasket. After breaking a fin I found these two pry points. When the head finally came free the gasket actually delaminated with half the gasket stuck to the head and the other half stuck to the cylinders. Imagine how much force it took to do that... (hint: A LOT)

Damn P.O.'s...  >:(
TAMTF...


Wilbur



Projects:
"Evolution": http://forums.sohc4.net/index.php?topic=100352.0
"P.O. Debacle": http://forums.sohc4.net/index.php/topic,126692.msg1441661.html#msg1441661
F2/F3 O-rings: http://forums.sohc4.net/index.php?topic=113672.msg1300721#msg1300721
Cam Tower Studs: https://www.mcmaster.com/#93210a017/=t19sgp
Clean up that nasty harness: http://forums.sohc4.net/index.php?topic=137351.msg1549191#msg1549191
http://forums.sohc4.net/index.php/topic,148188.msg1688494.html#msg1688494
http://forums.sohc4.net/index.php/topic,139544.msg1579364.html#msg1579364
                                          
Charging system diagnosis: http://forums.sohc4.net/index.php?topic=1012.msg8345#msg8345
Get the manuals: http://manuals.sohc4.net/cb750k/
The Dragon: http://forums.sohc4.net/index.php?topic=45183.msg1571675#msg1571675
Headlight Switch: http://forums.sohc4.net/index.php?topic=113986.msg1283236#msg1283236
Branden's leak free top end thread: http://forums.sohc4.net/index.php?topic=107040.0
Engine Lifting Made Easy: http://forums.sohc4.net/index.php/topic,58210.msg1684742.html#msg1684742
                                      http://forums.sohc4.net/index.php/topic,100352.msg1675840.html#msg1675840
Static and Dynamic Timing: http://www.hondachopper.com/garage/carb_info/timing/timing1.html
Airbox Gasket Replacement: http://forums.sohc4.net/index.php/topic,114485.msg1290000.html#msg1290000
"Café" : http://forums.sohc4.net/index.php/topic,84697.msg953814.html#msg953814
PD Carb Choke Linkage: http://forums.sohc4.net/index.php/topic,100352.msg1669248.html#msg1669248
                                    http://forums.sohc4.net/index.php/topic,110931.msg1248354.html#msg1248354
                                    http://forums.sohc4.net/index.php/topic,48858.msg515204.html#msg515204
Follow up on your damn posts: http://forums.sohc4.net/index.php/topic,144305.msg1791605.html#msg1791605
Taiwanese Cam Chain Tensioners:  http://forums.sohc4.net/index.php/topic,155043.msg1774841.html#msg1774841
Gumtwo Seat Cover: http://forums.sohc4.net/index.php/topic,164440.msg1897366.html#msg1897366
Primary Drive: http://forums.sohc4.net/index.php/topic,166063.msg1919278.html#msg1919278
Tank Latch: http://forums.sohc4.net/index.php/topic,165975.msg1919495.html#msg1919495
Shorten your forks: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-shorten-forks-td4042465.html DO NOT CUT THE SPRINGS!
Clutch How To: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-change-and-adjust-a-clutch-SOHC-td4040391.html
Late model K7/K8/F2/F3 front sprocket cover removal: http://forums.sohc4.net/index.php/topic,178428.msg2072279.html#msg2072279
630 to 530 conversion: http://forums.sohc4.net/index.php/topic,180710.msg2094423.html#msg2094423

Sent from my Tandy TRS-80!

Offline tool14

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Re: CB750 K series cylinder head removal
« Reply #4 on: May 23, 2021, 03:38:51 PM »
welcome aboard

Offline newday777

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Re: CB750 K series cylinder head removal
« Reply #5 on: June 20, 2021, 03:51:33 AM »
Hi,
I am obviously new to this forum. I have read lots of internet posts concerning the removal of the cylinder head of a cb750, most of which are brutal involving driving wedges, hitting various parts of the casting - even dropping the head/block on various media. Most of these methods guarantee to damage the quite delicate castings and/or mating faces. I have devised a simple tool to separate the head from the cylinders gradually and safely. Would this be of use to anybody or has this issue been solved a long time ago ?

best

John
Sounds like a sales pitch......
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A