Z1OwnersClub GB

Hi' All Got a problem with my Head Bolts, Bought some ape studs and they don't seem long enough, Only 3 to 4 thread's showing on inner studs, It's a Z1000j Bottom end and a GPZ1100 uni head, not sure what year, it was on when I bought it, any body had this problem, I tried to order some longer studs but was told all the Big Z engine stud kit's are the same length, the studs that I removed were all loose, look's like they were screwd out to make them longer, can ya'get longer studs or do I have to get the Head milled around the stud hole's......

are they the same lenghts as the originals? studs are measure from the end of the stud to the bottom of the thread on the oposite side of the stud

stud lenghts

outside studs 158mm

inner studs 133mm

centre studs 167mm

Those HD studs don't always have to be bottomed out in the cases, especially if someone has run a tap down the cases to clean the threads and cut them deeper.
You need to set the height you need then apply stud lock and leave them to set.
You do need them inserted at least the same depth as their width though(i.e. 12mm ) and preferably more.
If this isn't possible then something is going on with the barrel deck height etc.
There is always scope to fit barrel spacers etc with these studs so they should be plenty long enough unless you have been sold Z650 ones by mistake, check the length of the APE studs against your original ones to be sure, they should be at least the same length or slightly longer.

I had a word with A well known Z dealer at stafford, He said the Uni head is differant at the inner stud hole's ie' thiker or higher, some one else said screw them out slightly and lock tight em'in, as long as no thread is showing above the case, just wanted to see if anybody else had come across this before, don't fancy messing around getting it milled, just after I've had it powder coated...

all j type motors including the gpz 1100 a1/a2 uni trak use the same studs

Also when setting stud height - make sure they aint too high as the nut will bottom on the stud & not against the head - it'll be loose

Pigford wrote:Also when setting stud height - make sure they aint too high as the nut will bottom on the stud & not against the head - it'll be loose

top tip mark.

ADRIAN H wrote:

Pigford wrote:Also when setting stud height - make sure they aint too high as the nut will bottom on the stud & not against the head - it'll be loose

top tip mark.

Why yes - it was one of my better replies

Actually Mark it's your best reply ever

Z1parR wrote:Actually Mark it's your best reply ever

Do you know, I believe it may well be

Do I get a prize

Pigford wrote:

Z1parR wrote:Actually Mark it's your best reply ever

Do you know, I believe it may well be

Do I get a prize

The satisfaction that it's a good tip shared

z1bman wrote:all j type motors including the gpz 1100 a1/a2 uni trak use the same studs

That make's sence, when I tried to order some longer one's, He said the same, I'll lift the barrel's tomorrow and see how far the stud's are going in the case's, If the thread keep's going inside the case, I'll stop level with the top and lock tight them in, Thank's for reply's Lad's....

blackie wrote:I had a word with A well known Z dealer at stafford, He said the Uni head is differant at the inner stud hole's ie' thiker or higher,

It is the casting above and around the combustion chambers that is thicker on the twin swirl / bathtub Unitrack and 83 on Z1100 heads but the height of the head where the stud washers and nuts sit is the same as all z900/1000 etc and therefore use the same length stud.
When setting the stud height leave 12mm protruding above the head with all gaskets fitted.

Here we go for the second PEARL of WISDOM:

Put some heat/shrink wrap around the head studs - it looks good, protects them and is really cool - as Rob (Zed1015) does on his masterpieces

zed1015 wrote:

blackie wrote:I had a word with A well known Z dealer at stafford, He said the Uni head is differant at the inner stud hole's ie' thiker or higher,

It is the casting above and around the combustion chambers that is thicker on the twin swirl / bathtub Unitrack and 83 on Z1100 heads but the height of the head where the stud washers and nuts sit is the same as all z900/1000 etc and therefore use the same length stud.
When setting the stud height leave 12mm protruding above the head with all gaskets fitted.

12mm above, will see tomorrow, Don't know why he said I need longer stud's in the middle, or mill some off, just goes to show the expert's get it wrong aswell, Thank's for the info...