Need new headbolt/is my piston burned?

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Keepthedrivetommy

Guest
Anyone know where I can buy a new headbolt, just the headbolt? I stripped the top of one of them, and the nut wont screw on now. I figured that it wouldnt be safe to ride with one nut missing, so I didnt ride.

Also, once I get one, how do I tighten it as much as possible without stripping the threads?

And finally,
I checked my piston, and the top of it is mostly covered with oil/gunk. Some of it can be scratched away with a fingernail while most of it has hardened. Is this how the piston is supposed to be?
 


M

mickey

Guest
When I broke my cylinder stud, I had to buy stainless threaded rod from a local fastener shop and cut it with my dremel. On the plus side, a meter of 6mm rod cost about $4 and can be used to fix broken mounting studs as well. They're all 6mm rod on my Kings "80".

Edit: How much to torque the head bolts was the first question I asked on this forum. At that time the consensus was even and firm, tightening in a cross pattern, rather than a specific in/lbs. Since then, other posts have been made listing specific torques but I've just kept to palming the end of the socket wrench and tightening firm and even.
 
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M

mickey

Guest
what tool did you use to tighten it?

A regular ratchet wrench with the end in my palm so that I can't get any leverage. Am I saying that in a way that makes sense?

Edit: Buy some anti-seize stuff to use when you replace the cylinder stud. Its better for the aluminum block if you use it. Its next to the locktite in the stores. (if you're not familiar with the stuff)
 
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K

Keepthedrivetommy

Guest
not exactly. Mostly, Im worried about stripping the threads. So wouldnt a ratchet wrench grind the threads away?
 
M

mickey

Guest
not exactly. Mostly, Im worried about stripping the threads. So wouldnt a ratchet wrench grind the threads away?

Well, any wrench will strip the threads or pop the stud if you tighten down too hard. If I was using a box end wrench, I'd try to only turn it with one finger or something like that, without going all the way out to the end of the 'lever'.

Edit: How about this for a image, the end that is in my palm is the ratchet end. So my lever is only half the width of my palm. Sort of. :D

A search on headbolt + torque brought up this thread
 
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mickey

Guest
but the heabolts have to be really tight or they wont stay in.

Fairly tight yes. Again, not so tight that they strip out. The block is aluminum of suspicious quality. Much worse if you strip the studs out of the block than if you just break a stud or strip the thread at the nut end.

Did you actually strip the threads on the stud? That's odd. I would think that its easier to pop the stud in two than to strip the thread where the nut goes. Maybe you were crossthreading the nut. Can you post a picture of the damage?
 
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M

mickey

Guest
what tool did you use to tighten it?

Maybe I misunderstood this question. Are you asking what I used to replace the stud? I took the cylinder off to allow some room and used the 2 nut technique. Put 2 nuts on the rod or stud and tighten them one against the other. then use one of the nuts to tighten or loosen the stud (the one whose turning would make it tighter against the other one. ie. Bottom nut to loosen, top nut to tighten.) That leaves the threads undamaged.

Edit: I misspoke earlier, I just took the head off. There was no need to remove the whole cylinder.
 
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