Head bolts

jmesser80

Member
Sep 11, 2013
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Claremont New Hampshire
I've searched this topic but can't seem to find what I'm looking for.

My 99 blaster head bolts keep loosening up, I use a torque wrench and follow the pattern and they tighten up no problem. I go out riding and check them the next day and they loosen up.

My question being if I replace the head gasket will that take care of them loosening up? Or is there something else going on?

I just don't want to start replacing anything major if it is something simple. Thanks in advance
 
do you have the washers installed?
are the studs moving/or messed up threads?
are they stock bolts or did you get them at hardware store:)
 
oops i typed bolts to lol
i meant NUTS....sucking me in to there dillusions:)

Nuts large.jpg
 
If the nuts have been over tightened at anytime the threads of the studs and nut could be stretched.

This could cause them to back off.

Has the engine ever been heat cycled?
 
do you have the washers installed?
are the studs moving/or messed up threads?
are they stock bolts or did you get them at hardware store:)
The washers are installed and the studs do not move. They tighten down fine but when I check them the day after a ride they are loose. They are stock bolts.

I'm not sure what heat cycling is so I will read up on that but as far as I know it has not. Previous owner might have but highly doubtful. I myself have not over tightened the bolts I always use a torque wrench to be safe. But again previous owner might have over tightened.
 
did you ever take the head off?
or just checking them? Or why did you take the head off lol

are you taking the gas tank off everytime you check them? It is a tight fit?
 
It sounds like the studs are pulling the threads out of the cylinder, or perhaps the studs are not snug in the cylinder to begin with. May I make a suggestion? >>> Wash the bike, REMOVE THE TANK, REMOVE THE HEAD, then inspect the cylinder studs.
 
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I take the tank off to torque them.
The studs are not pulling out they are tight. The threads on the studs look good. Threw a die on them and was nice and smooth no slop.
I may buy new stock nuts and see what happens.

Does anyone know the size, grade and thread pitch of the stock bolts? There is a fastenal down the road may run out there tomorrow

And thank you for all the support.
 
If you threw a die on there, get the size and tread pitch off of that. I can't help other than that...lol
 
Thank you for the info it has been most helpful. Will probably just order up the stock nuts and go from there.
Will take a look to see if the head is warped while it is off.

Thanks again.