Topic: Installing HD cylinder studs on a CB550

[akabek]

I am in the process of rebuilding my motor and I purchased the HD cylinder studs from Dynoman.  They sent me instructions on the torque setting once the head is on but I am not sure what the torque setting should be used to put them in the crankcase.  This is what I found on the APE website for my bike.

CS500H (Honda CB500/550/650 fours) CYLINDER STUD INSTALLATION INSTRUCTIONS

1. Long threaded end must be installed in the case.

2. Note stock stud length location before removing. There are two different stud lengths.

3. After removal of stock studs (removal tool #SP-100 available from APE) thoroughly clean holes with solvent and blow out.

4. Use APE stud installation tool #08-151 or two 8x1.25mm nuts on the noted location, bottoming out, then using a torque wrench torque to 8 ft. lbs. maximum.

4. Install head, and following manufacturer's torque pattern, torque nuts to 20-22 ft. lbs.

Some folks put lube on the threads and some leave it dry when installing studs in the crankcase but does 8ft lbs dry sound right?

[bwaller]

Lightly oil the threads and torque to 8ft/lbs.

[akabek]

Lightly oil the threads and torque to 8ft/lbs.

Good thing I checked.  I would have thought more than 8lbs of torque....thanks

[akabek]

I have read issues with breaking new APE studs when torquing them down.  Is the recommended 20-22 ft. lbs correct if I lightly lube the threads?

[Sam Green Racing]

If you bought the studs from Dynoman, would it not make sense to ask HIM what the torque settings should be for the studs?

Sam.

[bwaller]

8lbs in the cases, then 20-22 MAX with 8mm head nuts. Make sure the surfaces are flat and while you're at it get new good quality 8mm flange nuts.

[akabek]

Thanks bwaller.

Dynoman gave me the same instructions as I posted above.  The reason I am asking is because I read some older posts where studs were installed to the recommended torque settings but they were snapping.  I am just double checking....

[akabek]

After the engine has been assembled and the bike ridden for a bit is it good policy to re-torque the stud nuts again?

[bwaller]

Using copper or MLS I see no need. I for one have only done it once because of an oil weep and didn't gain anything.

[johno]

Generally a 750 engine in a 750 frame is a pain in the butt to retension so I got into the habit of not doing it.  I do however spend some quality time prepping and torquing to help the cause, eg I run a die nut over every stud evan if its brand new and tap through every nut. I use a moly lube on the thread and base of nut when tensioning. After tensioning I like to let the motor sit for a week then I back of one nut at a time, relube and retension.     I  measured the extra angle the nut pulled up and decided to this everytime. Evan on the old type head gaskets that were famous for weeping this technique worked well for me. 
johno

[johno]

Oh !  re the stud install process , a long time ago I remember reading on a thread somewhere that Mike R had a way that he liked........from memory no tension and some medium grade retainer, I think it would have merit as with no tension into the case it would stop any distortion in that area. I havent tried it yet but might give it a go on the salt motor.........chime in Mike if I read it wrong
johno

[akabek]

^^ This thread is about a CB550, not a CB750

[johno]

So,      I reckon one of us missed the point mate ?  dig deep and have a think about it.

[akabek]

So,      I reckon one of us missed the point mate ?  dig deep and have a think about it.

My mistake. 

[johno]

Hi Akabek,
Its cool.....I was hoping the additional information would help.  You know any stock type composite gasket compressed will settle and  the pre  tensioning of the stud helps to compensate for that. The original stud design is clever engineering based on dealing with that issue but just like us ol man time marchs on and the original studs are tired, stretched past their max elasticity, often combined with a cheap a#se chinese made composite paper mache head gasket that needs about twice the clamping effort to seal anyway , bad result...and thats on a stock motor !
So imagine if your upping the ante with performance mods creating more cylinder pressure, higher operating temperature, unevan cooling to areas then the well engineered poor old stock studs have to go.
In fact in my humble opinion it is one of the most important modifications that can be done to enhance reliability on any japanese bike produced in the 70,s.
 Akabek life is good for you man, there are a couple of hi quality gaskets retailed now, just spend the extra cost and feel good about your decision.
Re the studs install I would just follow the instructions with two proviso's, chamfer the case hole with a nice chamfering tool  and big fat dont wind the new studs in with multi grips or such scratch device
And check there is not enough lube in the bottom of the hole that would hydraulic crack the cases, when they say lightly oil they mean lightly oil not dripping in the hole.

I was a bit short yesterday Akaben, I was booked to fly overseas on Sunday for two weeks , on Saturday arvo I booked myself into a hospital thought I was dying, got Hooping cough, feel like sh#t, doc wouldnt let me fly,  back home today and all my plans out the window, Mikes photos of my new LSR head cheered me up and Ive enjoyed chatting with you,
cheers johno

[akabek]

Hey Johno, when I did the engine work over the winter I had it bored out and installed 592 Dynoman pistons and completed the install with a quality MLS head gasket and APE studs. 

A couple of nights ago I took the bike out for a ride and noticed some light brown splatter on my the top of the crankcase and the outside of the float bowl.  At first I thought I may be leaking oil but I could not find any oil leaks on the motor.

On the side of the CR29 carbs there is a black plastic elbow that you can rotate.  I have no idea if this is a vent or some type of overflow.  In the center of the pic below the guy has a tube connected to it.  I have a feeling the splatter came from the elbow so I will connect a tube to it and run it below the motor.

http://www.flickr.com/photos/78038571@N00/2331349194#