Author Topic: CB750K0 Camshaft Holder Stud Torque Spec  (Read 1521 times)

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Offline markb

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CB750K0 Camshaft Holder Stud Torque Spec
« on: December 16, 2007, 11:20:20 AM »
Does anyone know the torque spec for the 6mm studs that go into the top of the cylinder for the camshaft holders?  I upgraded to APE studs for the cylinder and the spec into the case is 8 lbs.-ft. which is about half the torque for the head nuts with standard studs.  So I figured about half the torque for a 6mm nut or about 3.5 lbs.-ft. (42 lbs.-in.) should be OK for the cylinder holder studs.  I wouldn't want them to come loose but I really don't want to crack the head.  Anyone know for sure?  BTW, does anyone know why there are studs on one side of the cam holder and screws on the other side - maybe to help align the holder on the pins without disturbing the sealing rubbers?
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Mark
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Offline 754

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Re: CB750K0 Camshaft Holder Stud Torque Spec
« Reply #1 on: December 16, 2007, 11:31:59 AM »
Are you assembling without a manual??

I would say the camholders are doweled to prevent alignment problems, only way they could work..
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Offline markb

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Re: CB750K0 Camshaft Holder Stud Torque Spec
« Reply #2 on: December 16, 2007, 01:03:54 PM »
I've got three manuals and two parts books.  None of them show the torque spec.  I've had this motor apart 3 times and never had to replace one of these studs but this time the nutted end didn't look too good on one so I replaced it.  You're right about the dowels doing the alignment, I was just thinking the studs may get it close so you have to go straight down before the holder engages with the dowels so that you don't disturb the sealing rings.  I was just curious as to why there was studs on one side and screws on the other.
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Offline markb

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Re: CB750K0 Camshaft Holder Stud Torque Spec
« Reply #3 on: December 16, 2007, 01:12:11 PM »
I just noticed a typo in my post that may be confusing.  I said cylinder holder when I meant cam holder.  Sorry.
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Offline Ellz10

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Re: CB750K0 Camshaft Holder Stud Torque Spec
« Reply #4 on: March 16, 2022, 10:18:36 PM »
I know this is an old post, but I'm curious if you ever found out what the correct torque spec was for the (4) head studs?

After looking thru Clymers and HondaMan's book (the specs weren't in either), the best I could come up with was an guess and that is around 7.5 ft lbs.

Is that right?
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Online bryanj

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Re: CB750K0 Camshaft Holder Stud Torque Spec
« Reply #5 on: March 17, 2022, 08:57:33 AM »
In all the Honda manuals is a table of "standard" torgu settings for unspecified bolts and you use that
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Re: CB750K0 Camshaft Holder Stud Torque Spec
« Reply #6 on: March 17, 2022, 07:27:26 PM »
I know this is an old post, but I'm curious if you ever found out what the correct torque spec was for the (4) head studs?

After looking thru Clymers and HondaMan's book (the specs weren't in either), the best I could come up with was an guess and that is around 7.5 ft lbs.

Is that right?

The general torque spec for 6mm bolts in the Honda engines is 70-100 in-lbs. They used 35 in-lbs for non-loaded bolts (like the 4 center ones in the rocker towers, which are merely locator bolts for engine assembly purposes) in some places, but most were 70-100 in-lbs. In the rocker bearing caps, I use 90 in-lbs to preclude possible oil weeping in the future underneath the cam bearings where those studs go all the way thru the head. There is not a large load on those studs, as the load is taken against the 4 dowels that hold the bearing assemblies in position.
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Offline Ellz10

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Re: CB750K0 Camshaft Holder Stud Torque Spec
« Reply #7 on: March 17, 2022, 11:12:37 PM »
I know this is an old post, but I'm curious if you ever found out what the correct torque spec was for the (4) head studs?

After looking thru Clymers and HondaMan's book (the specs weren't in either), the best I could come up with was an guess and that is around 7.5 ft lbs.

Is that right?

The general torque spec for 6mm bolts in the Honda engines is 70-100 in-lbs. They used 35 in-lbs for non-loaded bolts (like the 4 center ones in the rocker towers, which are merely locator bolts for engine assembly purposes) in some places, but most were 70-100 in-lbs. In the rocker bearing caps, I use 90 in-lbs to preclude possible oil weeping in the future underneath the cam bearings where those studs go all the way thru the head. There is not a large load on those studs, as the load is taken against the 4 dowels that hold the bearing assemblies in position.

Okay, so I was correct. Good to know, thank you!
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