Setting new cylinder studs - torque

motogroove

motogroove

New member
Looking for a torque spec.?
You will not find a torque setting for your studs, unlike other bikes.
You do not want to torque your studs.
You want to set the depth, leaving enough stud above the deck to hold the cylinder and the nut. This photo shows how the stud can be set too low. The stud in the photo is just about right, but note how much deeper it can go.

I learned this the hard way (months ago) - made a tool for torquing and used a YZ250 spec. Don't do what I did. You'll just end up backing them all out and setting the height.

HTH,
Dean
2001 xc300
 

Attachments

  • Cylinder-stud-set-height.jpg
    Cylinder-stud-set-height.jpg
    117.2 KB · Views: 51
Every application of studs on racing engines that I have built in the past studs were to be tightened finger tight only. If you torque them into a blind hole you are only putting them in a bind for no reason and risk distorting what ever they are screwed in to. Their holding power depends on the torque of the nut and the stretch of the stud and nothing to do with how much of a bind they are in by bottoming them in their foundation. Some may argue with what I'm saying but I have done this on 1,000+ hp alcohol injected V8 main caps and cylinder heads with no problems.
 
lankydoug said:
Their holding power depends on the torque of the nut and the stretch of the stud and nothing to do with how much of a bind they are in by bottoming them in their foundation. .
Click to expand...

Bingo! This is the other big truth that somebody pointed out to me back when I fumbled with the YZ torque spec. It makes total sense. :cool:
Thanks.

******

The note on the chart to loctite the studs on re-assembly could be a whole other discussion. But it makes enough sense to me for next time. It would be bad to have the studs loosen instead of the nut on those ones in the PV cover. Seems like the studs will grab pretty well in the alumninum anyway...
 
You must log in or register to reply here.
Back
Top