Cylinder head and cylinder Torque check.

Voodooo

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Cylinder head and cylinder Torque check.
I notice I have a “small” amount of oil seeping between the cylinder head and cylinder gasket on my commando. I only have 380 miles on the bike.

I’m going to check the torque on the head, do any of you also check the torque on the lower 5 front cylinder bolts when doing head torque check?
 
The workshop manual indicates 25nm for the barrel bolts but in a specific order - numerically from 16 to 20
The bolts are numbered (from left to right looking towards the back of the bike)
20 18 16 17 19
John

Cylinder head and cylinder Torque check.
 
View attachment 10496 I notice I have a “small” amount of oil seeping between the cylinder head and cylinder gasket on my commando. I only have 380 miles on the bike.

I’m going to check the torque on the head, do any of you also check the torque on the lower 5 front cylinder bolts when doing head torque check?

WOW , Your bike is clean Bro ! I just put a wrench and nip them up. Definitely do the head torque now Bro ! Also don't forget about the exhaust gasket leaks on the head pipes. May need a second gasket and a re-torque there too.
 
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I'm certain you received this info from me in one of my emails I sent out with manuals. But here it is again.

All of the bolts need to be torqued. The numbers are the order of which you do them. It's confusing because their are two numbers on some of them. Like 1/7. This means you are going to torque it twice. The first time and the seventh time. So on that bolt you torque it to 22ft lbs (30Nm) then the seventh time to 44 ft lbs (60Nm),. Hope this makes sense.
Torque One to Six to 30Nm. Torque Seven to Twelve to 60Nm, then torque thirteen to fifteen to 30Nm
If you get the WEB version of the service manual, the torque specs are wrong. Only the paper version is correct. Above are the correct values.
 
WOW , Your bike is clean Bro ! I just put a wrench and nip them up. Definitely do the head torque now Bro ! Also don't forget about the exhaust gasket leaks on the head pipes. May need a second gasket and a re-torque there too.
I’ve already replaced the header gaskets. My headers had some stains on them so I removed them to polish them. That’s when I noticed the minor oil from the head gasket.
 
I'm certain you received this info from me in one of my emails I sent out with manuals. But here it is again.

All of the bolts need to be torqued. The numbers are the order of which you do them. It's confusing because their are two numbers on some of them. Like 1/7. This means you are going to torque it twice. The first time and the seventh time. So on that bolt you torque it to 22ft lbs (30Nm) then the seventh time to 44 ft lbs (60Nm),. Hope this makes sense.
Torque One to Six to 30Nm. Torque Seven to Twelve to 60Nm, then torque thirteen to fifteen to 30Nm
If you get the WEB version of the service manual, the torque specs are wrong. Only the paper version is correct. Above are the correct values.
Correct. I’m aware of the torque spec and order. I just didn’t recall anyone mentioning the cylinder torque check. I appreciate all your help from everyone.
 
I’ve already replaced the header gaskets. My headers had some stains on them so I removed them to polish them. That’s when I noticed the minor oil from the head gasket.
Sometimes 2 gaskets per port work best.
 
I torqued my heads on both bikes today. I can’t believe they required 1 to 1-3/4 turns to reach spec torque values.
I did the torque sequence as shown and did them is 4 steps.

Anyone else get that many turns?
 
I torqued my heads on both bikes today. I can’t believe they required 1 to 1-3/4 turns to reach spec torque values.
I did the torque sequence as shown and did them is 4 steps.

Anyone else get that many turns?

Almost 2 threads??? Wow! No not even checked mine, it has had 2 dealer services so I would expect them to have been checked?
 
Almost 2 threads??? Wow! No not even checked mine, it has had 2 dealer services so I would expect them to have been checked?
2 of the 4 Acorn nuts were below 30 Nm. First I torqued them to 30 Nm in the sequence shown in the shop manual then finished at 60 Nm.
 
Yes , especially the left hand side needed the most turns for me . L/H acorn nuts . But i still have to say your bikes are clean guy !
 
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Yes , especially the left hand side needed the most turns for me . L/H acorn nuts . But i still have to say your bikes are clean guy !
My left side was looser than the right side as well. Lol thanks for the compliments.
 
Hi guys, looking at the thread I am wondering about the procedure at first service check for the head nut torque.
Do they just make visual check of the nut position vs white mark on washer and head to determine if it turned. Or they systematically apply torque sequence ?
Thanks.
 
Hi guys, looking at the thread I am wondering about the procedure at first service check for the head nut torque.
Do they just make visual check of the nut position vs white mark on washer and head to determine if it turned. Or they systematically apply torque sequence ?
Thanks.
Torque each nut to the correct spec following the torque sequence.
 
Hi Voodooo and TonyA
Thanks. But my question is about Norton requirement. Is it well to perform torque check ?
Or just visual check that the nut didn’t turn.
 
Torque check. A visual check won't reveal anything, a slight stretch on the studs or compression of the head mating surfaces will show up on the torque wrench but won't show visually by the nut moving.
 
Hi Voodooo and TonyA
Thanks. But my question is about Norton requirement. Is it well to perform torque check ?
Or just visual check that the nut didn’t turn.
They need retorqued. By visual inspection won’t do any good. You’ll be surprised how much they loosen from the heat cycles.
 
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