Topic: broken stud. part discontinued. arrggg!

[ultragoat]

So I'm putting my '78 750 motor back together. All is going well when I begin torquing down the cylinder head and then I hear the dreaded *SNAP* on the long 6X90 flange bolt. I get it out okay and go order another one from the local Honda shop. A week later I get it and get everything torqued down without any problems.

Then, I'm almost almost finishing putting the cam towers, camshaft etc. back together when I hear it again: SNAP! (note to self: get a better-than-harbor-freight torque wrench  ) This time the victim was one of the 6X58 studs that holds the cam tower to the head.  Now here's the problem: Honda had discontinued this part. I guess I could try and cut down a stud if it's similar. I'm also gonna take a trip out to the motorcycle graveyard tomorrow and see if they can help.

Other than that, does anyone know where I might possible find one of these suckers?

[Gaither]

Perhaps a local fastener supplier could match it up - including hardness [?].

You could ask in "parts wanted". Somebody has one.

[Leanier]

I actually did the same thing as you when putting my engine back together, couldn't find the stud anywhere, so what I ended up doing is finding a bolt with the same thread that goes into the engine, and cutting off the head, and buying a die that matched the thread of the nut, and making my own stud.  worked great! pretty cheap overall to, especially if you own the die already (which i didnt)

[rangelov]

A 6mm long bolt isn't exactly a structural member.  Make your own.  On some thing that small you should using an inch pound torque wrench.

Or better yet, don't use a torque wrench, do it by feel.  If you do enough 6mm bolts and studs, you can tell when they are tight enough, starting to strip, or about to snap.

A bad torque wrench, wrong scale, or incorrect published torque will get you in trouble.

Develop that feel, it might have saved this aggravation.  I don't think 6 mm screws should be torqued, especially when threaded into soft aluminum.

[scunny]

my GS1000 loved to break the cam tower bolts after a rebuild, bought new ones and no problem. must be made of jelly

[ultragoat]

Update: My local Honda shop said they could order some studs that are 2mm longer (6X60) that are meant for a different engine/manufacturer so we'll see if those work (fingers crossed). I'll go a little easier on the torquing this time. Thanks for all your suggestions.