torque head

GoldenMotor.com

Zearobiker

New Member
Jul 11, 2015
23
0
0
reading pa
This is my 2nd motor but first time rebilding one top end i can not find how tight to make head bolts is here any info on it or you just go by fell and hope you dont brake them.crt.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
We generally recommend 120 to 140 inch pounds. This is for a stock cylinder head using the kit supplied head gasket.

We also always suggest you discard the chrome acorn nuts in favor of standard or flanged hex nuts. The acorns are notorious for bottoming out on the stud before applying sufficient clamping force to the head.

We also like to see the cylinder head gasket surface be 'lapped' for a good gasket seal prior to reassembly.

Tom
 

Zearobiker

New Member
Jul 11, 2015
23
0
0
reading pa
Thanks for the help just wish there was a shop in pa like out there but in pa dont have any i can find just one on line sale again. Thanks .crt.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
You don't need a "shop". All you need is a sheet of sandpaper, a piece of glass, or any flat surface like dry wall or masonite.

Lay the sandpaper, something like 200 grit, face up on the flat surface then swipe the cylinder head across it several times. You'll quickly see if there are any high or low areas on the gasket sealing surface of the head. I always recommend that you 'paint' that surface with a Magic Marrker, or machinist dye before sanding. That will give you a good indication of any imprefections after a couple of light swipes across the sandpaper.

If you see no indication that the surface isn't flat then simply install the head using the torque values given above. If you do see high and low areas, which is common, keep sanding as you rotate the head in your hand making circular motions as if you're applying wax to a car until the surface is uniform. You do want to be careful and not sand an angle into the head which is why you rotate the head as you sand. Go slow, don't apply too much pressure and you'll finish with a 'lapped' gasket surface that is better than what the factory provided.


This same method can be used to get a good gasket seal on the intake and exhaust manifold flanges.
Good luck.

Tom
 

Zearobiker

New Member
Jul 11, 2015
23
0
0
reading pa
Thanks for the info i have order parts on line got some hade some never show they took my money but no parts and they never get back to me on what happend that y i would like to to find a place to go and get my parts east cost seams like there not to many people with gas bicycle thanks again
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
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USA
NOTE: no one mentioned that if head studs are only 6mm, then torque is only 6 to 8 foot/pounds
 

Zearobiker

New Member
Jul 11, 2015
23
0
0
reading pa
Thanks for he onfo got motor runing but after i let it set for night wont start got gas and spark new plug dont know why it wont start all new top end ranbafter i did work now wont make a chace fo start
cvlt1