Torque

[twocool]

Somebody made a post and mentioned breaking some bolts on an engine cover.

FYI torque spec....(from Suzuki manual)

For engine case:
 
6mm Bolts ....6.5 ~ 9.5 lb-ft
8mm Bolts .... 14.6~17.4 lb-ft

Other bolts "conventional" type 4:

5mm.....1.5 ~ 3.0 lb-ft
6mm.....3.0 ~ 5.0 lb-ft
8mm.....7.0 ~ 11.0 lb-ft

These are all pretty low torque numbers so go easy!

Cookie

[tt_four]

I'm really surprised those bolts broke before their engine case stripped out. Stripping stuff like that is my worst nightmare when I'm working on engines 

[twocool]

I'm really surprised those bolts broke before their engine case stripped out. Stripping stuff like that is my worst nightmare when I'm working on engines 

I think it's a 50-50 shot on whether you break the bold or strip the case.  Steel bolts into aluminum is always a problem....

I think what breaks a bolt first is the fact that you've got the bolt deep into the aluminum threads..so the bolt has lots of support and the force is distributed over lots of threads.  As you apply torque, all the force is concentrated directly under the bolt head, or where the threads meet the shoulder.  Sometimes with a box wrench or socket, you end up putting on some side load as well...then snap!

Although many on this group say otherwise, I'll still believe in using a torque wrench...Hard to "judge" 1.5 to 3 lb-ft..  (18 ` 36 lb-in.)

Cookie

[tt_four]

I ALWAYS use a torque wrench now. I've destroyed too many things in my life without one, and I absolutely hate that feeling where you think "ok, just turn the wrench one more degree and I think I'll be good" and then all of a sudden there's no more resistance.

[reload]

during one terrible day of wrenching I stretched and snapped one case bolt...but no worries i have a spare bolt to use. then i stripped out the internal threads. sonofagun that was stressful.

ordered a helicoil thread repair set and a couple days later was back to riding.

[BaltimoreGS]

I'm not advocating not using a torque wrench but the GS aluminum is pretty forgiving.  The softest aluminum case I ever dealt with was an older Ducati monster.  I did strip a case bolt hole on it by not using a torque wrench.  My fault.  Then I stripped another one using a torque wrench.  WTF!  That was the end of my Ducati days   

-Jessie

[Jared]

My God.... someone actually says it the right way.......Hang on... I'm still dizzy....

If you don't have a torque wrench you just tighten it till your teeth almost touch... (YES THAT'S A JOKE).

I have a Clicker (Husky) and an old bar style torque wrench (been so long I can't remember but I think Craftsman). Any time I'm in aluminum it gets used (tip- don't store your clicker  torque wrenches dialed in- run it back to zero).