Author Topic: Decking/milling 750 heads  (Read 1095 times)

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Offline ekim98

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Decking/milling 750 heads
« on: June 20, 2008, 04:10:17 pm »
How much can a 78 750k head be milled/decked without causeing valve/piston problems and cam chain issues?
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Offline MRieck

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Re: Decking/milling 750 heads
« Reply #1 on: June 20, 2008, 07:58:16 pm »
How much can a 78 750k head be milled/decked without causeing valve/piston problems and cam chain issues?
Ask DKay. He knows
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Offline MRieck

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Re: Decking/milling 750 heads
« Reply #2 on: June 21, 2008, 11:32:00 am »
 You can go at least .020 (total) with stock components
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Offline ekim98

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Re: Decking/milling 750 heads
« Reply #3 on: June 21, 2008, 11:40:13 am »
You can go at least .020 (total) with stock components

Thank you, I had my head check for flatness and it looks like it has a .005"/.006" bow. Most is right around the cam chain tunnel. The cylinder block was less than .002" so it's good I'd say. Il just didn't know how much could be milled off and not cause problems.
Patriot Guard Rider - KY. Ride with Respect

78 750k  cafe bike sort of
67 305  Superhawk (working project)

Offline MRieck

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Re: Decking/milling 750 heads
« Reply #4 on: June 21, 2008, 07:06:57 pm »
You can go at least .020 (total) with stock components

Thank you, I had my head check for flatness and it looks like it has a .005"/.006" bow. Most is right around the cam chain tunnel. The cylinder block was less than .002" so it's good I'd say. Il just didn't know how much could be milled off and not cause problems.
One of the board members head required about .017 or so off the top to get it flat ( a lot but it was a very early head). Keep in mind the cam tower rubber disc holes and the oil feed holes had to be countersunk after removing this much material off the top. The bottom only needed about .005 as it had been previously milled. You will need to kiss those holes mentioned on the top if you take .005/.006 off
Owner of the "Million Dollar CB"