I think I'd like to change my tappet cover studs for normal bolts!!!

Smeggy

XS650 Member
Messages
27
Reaction score
24
Points
3
Location
Glasgow, Scotland
Good Evening from Scotland, you beautiful people.
Long vertical studs pulling the engine together I get - but
WHY DO WE HAVE STUDS FOR THE TAPPET COVERS?
What is the engineering there?
 

5twins

XS650 Guru
Top Contributor
Messages
23,456
Reaction score
19,647
Points
813
I think repeatedly threading a nut on a steel stud holds up better than tightening a bolt into an alloy head. I wouldn't change them.
 

Smeggy

XS650 Member
Messages
27
Reaction score
24
Points
3
Location
Glasgow, Scotland
Good Evening from Scotland, you beautiful people.
Long vertical studs pulling the engine together I get - but
WHY DO WE HAVE STUDS FOR THE TAPPET COVERS?
What is the engineering there?
 

Attachments

  • rocker covers scews or studs.jpg
    rocker covers scews or studs.jpg
    187.2 KB · Views: 34

kshansen

XS650 Guru
Top Contributor
Messages
1,426
Reaction score
6,147
Points
513
Location
Central NY USA
One thought I might have if replacing the studs with bolts would to first install steel thread inserts. Have not looked to see if there is room for keenserts (not sure of the spelling and seem to be having trouble doing a google search). Maybe less desirable would be Heilicoil inserts(again not sure on spelling)!
 

jpdevol

XS650 Guru
Top Contributor
XS650.com Supporter
Messages
1,377
Reaction score
2,880
Points
263
Location
26187
Well now! Those flanged socket-head bolts DO look good - differentđź‘Ť

Oops! Button-head (need new glasses) - still look good - but maybe flanged allen better??
 

Smeggy

XS650 Member
Messages
27
Reaction score
24
Points
3
Location
Glasgow, Scotland
I think repeatedly threading a nut on a steel stud holds up better than tightening a bolt into an alloy head. I wouldn't change them.
Yes. That is it! Thank you.
So rather than regularly tighten/untighten hard steel into soft aluminium, screw a steel stud deep into the aluminium only once - then every time you take a tappet cover off you are steel on steel!!! Got it, Brilliant. Thanks again, that was close!!
 

jpdevol

XS650 Guru
Top Contributor
XS650.com Supporter
Messages
1,377
Reaction score
2,880
Points
263
Location
26187
You realize that's strictly form over function.....but that's also we motorcyclists being "rugged individualists" lol
 

5twins

XS650 Guru
Top Contributor
Messages
23,456
Reaction score
19,647
Points
813
I've run across many more stripped engine case screws than I have valve cover studs.
 

xjwmx

Ad lunam et stellas!
Top Contributor
Messages
7,926
Reaction score
4,428
Points
313
Location
U.S.A.
Mind yer torque specs and you should last without stripping 'em outta the head.
The usual suspect is the front right bottom one. I think red locktite to keep it from turning would keep it from stripping, on the theory that it has to turn before it can strip the threads it's in. It could still just pull the eff out but it would take a lot more force. Also, you have your choice of gasket or big o-ring on those. I think the o-ring takes less torque to get sealing.
 

jpdevol

XS650 Guru
Top Contributor
XS650.com Supporter
Messages
1,377
Reaction score
2,880
Points
263
Location
26187
Yea, unless a previous "issue", 7ftlbs - even on the 8mm - should be plenty tight. If not sealed, it's another problem
 

5twins

XS650 Guru
Top Contributor
Messages
23,456
Reaction score
19,647
Points
813
Honestly, I'm surprised they work as well as they do, lol. The acorn nuts stay tight even without lock washers, and the covers usually seal up fine if the o-rings (or gaskets) are OK. The o-ring has a rather oddball 2.8mm diameter. I use 3mm ones, they fit fine and I think they seal even better, and they're easy to get.
 
Top