Topic: CB550 APE cylinder stud torque specs?

[RatFink84]

Does anybody know the APE cylinder stud torque spec for a CB550? I checked the website but it doesn't list the model and Im not sure if they are 10mm studs.

Thanks in advance
Kevin

[paulages]

22 ft#, but be careful... several people (including myself) have broken some recently.

[RatFink84]

Thanks for the warning, but is there any way to avoid breaking them (like only torquing to 19-21)? or is that not enough torque for these studs? Broken stud is what I am fixing with the APE studs and I would hate to break another.

[MCRider]

Thanks for the warning, but is there any way to avoid breaking them (like only torquing to 19-21)? or is that not enough torque for these studs? Broken stud is what I am fixing with the APE studs and I would hate to break another.

My feeling is that unless you have huge HP or a turbo or such, I would only use the studs to go to the top of the rather wide range for that stud. Probably like 18lbs or so. (The CB750 range is 14.5 to 18, I've seen stock studs give it up at 18lbs.) Maybe 10% more like you say 19-21. What you will have accomlished is a comfortable max stock torque and the piece of mind that all studs/nuts are even and not likely to loosen up. And less chance of breaking the stud.

The high end of the stock range should be plenty IMO.

[paulages]

Thanks for the warning, but is there any way to avoid breaking them (like only torquing to 19-21)? or is that not enough torque for these studs? Broken stud is what I am fixing with the APE studs and I would hate to break another.

My feeling is that unless you have huge HP or a turbo or such, I would only use the studs to go to the top of the rather wide range for that stud. Probably like 18lbs or so. (The CB750 range is 14.5 to 18, I've seen stock studs give it up at 18lbs.) Maybe 10% more like you say 19-21. What you will have accomlished is a comfortable max stock torque and the piece of mind that all studs/nuts are even and not likely to loosen up. And less chance of breaking the stud.

The high end of the stock range should be plenty IMO.

I agree. I believe the APE studs are 18-22 range. Unless running massive torque, I think 19-20 will be plenty.

[Flying J]

Just so nobody makes the same mistake twice here is the info from APE
http://www.aperaceparts.com/tech/cs900h.html
CS500H 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.