Author Topic: milling head  (Read 2271 times)

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Offline 77hotrodhonda

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milling head
« on: June 25, 2012, 07:13:42 AM »
Question. My 77 needs a head gasket so its time to freshen up the head. When i take it in to have it milled, how far can i take it safely? I want some more compresssion an im gonna put a mild cam in. Just tryin to get a little more bang with out putting in bigger pistons. Probably gonna have it ported with fresh valve springs as well
77 750K some might think I stole it cuz that's how I ride it

Offline Sam Green Racing

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Re: milling head
« Reply #1 on: June 25, 2012, 09:06:34 AM »
Have a word with Mike Rieck, he is a master porter/tuner, hundreds on here have had him do heads for them and as far away as Australia. Here's his profile.

http://forums.sohc4.net/index.php?action=profile;u=49

Sam. ;)
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Offline MRieck

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Re: milling head
« Reply #2 on: June 25, 2012, 10:54:34 AM »
Question. My 77 needs a head gasket so its time to freshen up the head. When i take it in to have it milled, how far can i take it safely? I want some more compresssion an im gonna put a mild cam in. Just tryin to get a little more bang with out putting in bigger pistons. Probably gonna have it ported with fresh valve springs as well
You can take about .045 off a late model head with just hitting the intake seat.
Owner of the "Million Dollar CB"

Offline 77hotrodhonda

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Re: milling head
« Reply #3 on: June 25, 2012, 11:49:44 AM »
So if i take 40 it will be plenty safe?
77 750K some might think I stole it cuz that's how I ride it

Offline PeWe

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Re: milling head
« Reply #4 on: June 25, 2012, 01:00:11 PM »
MLS gasket is thinner than the old style of head gasket, you get some extra compression.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
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 77hotrodhonda

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Re: milling head
« Reply #5 on: June 25, 2012, 04:08:01 PM »
Also do you think i caan get away with milling the head, adding the cam with new springs and guides without getting HD Head studs?
77 750K some might think I stole it cuz that's how I ride it

Offline Big Jay

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Re: milling head
« Reply #6 on: June 25, 2012, 08:46:31 PM »
Also do you think i caan get away with milling the head, adding the cam with new springs and guides without getting HD Head studs?

Why would you want to do that? How many imes do you want to have it apart?

Offline 77hotrodhonda

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Re: milling head
« Reply #7 on: June 25, 2012, 09:37:46 PM »
Idk cycle x swears by em. And being that im trying to raise compression i was wondering if it would be necessary
77 750K some might think I stole it cuz that's how I ride it

Offline PeWe

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Re: milling head
« Reply #8 on: June 26, 2012, 02:52:49 AM »
If you need more power, upgrade when it might need new parts anyway.
Why not a 836cc kit? like this..  http://cbrzone.com/sohc.html
On top of this ported head.

I have similar on my bike and it turned to be a very good touring machine. 2 persons + luggage on the bike, driving all day long (except for gas stop) 150-200km/hour, no problem with nice acceleration. My cam was mild, 0.360 lift, 270 degrees duration. Perfect for street and touring.

I'll go for a hotter cam now since my touring days are over with my bike. I need new thrills next time on the streets again.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
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 bear

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Re: milling head
« Reply #9 on: June 26, 2012, 08:05:54 AM »
Idk cycle x swears by em. And being that im trying to raise compression i was wondering if it would be necessary

Yes you will need HD studs or you will find yourself replacing head gaskets.
Nuts as well.

Cheers,
Brian
The older I get the faster I was.

Offline 77hotrodhonda

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Re: milling head
« Reply #10 on: June 27, 2012, 04:54:22 PM »
The 836 is a very popular set up. I was gonna try to get the most out of the 750, although i probably wont get what i want ultimately.
77 750K some might think I stole it cuz that's how I ride it