Making the thin headgasket out of the stock one

dnale

dnale

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South Lyon, Michigan
Ok, I'm going to be finally putting the motor back together. I have a new stock hg for a 96. I should have bought one for the 95 since it's already the thin one. Oh well, I didn't.

I know I can seperate the stock one. What of the stock one am I supposed to use? I had a thin hg on it before (was told that) and it looks like 3 thin peices. I know once I seperate I then spray gasket it to tack it and then install.

Thanks.
 
yea use a outer one. the inner one doesnt have a ridge for the coolant passages and thoes may help it seal. if they didnt i dont know why they would have them.
 
FuzzButt, Hit the nail on the head....

terret725, you think I am funny....well I dont...LOL, I like the truth and not to misguide but I have done dozens of head gasket mods and fuzzbutt does it the same way I do. Most middle layers are non coated and mainly a spacer, the outers are the parts that are reusable if the coating is still in good shape.

:whine: :whine: :dunno:
 
dnale, If your sled had a thin gasket in the beginning and ran it the way you did and didn't hurt anything you should be fine. Did you check the compression before?? If you did, then you can compare it to what you just did, You should be fine as far as jetting goes. Good Luck! T
 
there are a bunch of us that have done the mod...as MrSled and other have said use one of the outer gaskets and spray it and re-install.
I have about 4500 trouble free Km with only one layer installed and there is a difference.
 
One layer? Most of the older posts say to drill out the rivet and remove the inner layer and use TWO outer layers as this is a three layer gasket (at least on the 96 vmax xt 600). Other posters have said to buy the 95 vmax gasket and it is already thinner.

Somebody clear this one up as I am getting ready to do mine.
;):D
 
Yes I had the thin hg before. I check compression (right before I lost a ring, hence the rebuild) and it was low. I don't remember exactly somewhere over 100psi, but not much. I still have the "old" thin hg. I know it doesn't have the thicker spacer in the middle.
 
AIRBLUE said:
One layer? Most of the older posts say to drill out the rivet and remove the inner layer and use TWO outer layers as this is a three layer gasket (at least on the 96 vmax xt 600). Other posters have said to buy the 95 vmax gasket and it is already thinner.

Somebody clear this one up as I am getting ready to do mine.
;):D
Click to expand...
The "two layer" approach is the "87" octane safe mod. You raise the compression a little but not enough to require 91 all the time.

Still worth it though.

Yes the gasket is a 3 piece assembly. There are 2 small rivets on opposite corners holding it together. Drill out the rivet carefully and the gasket is seperated.
 
FuzzButt said:
The "two layer" approach is the "87" octane safe mod. You raise the compression a little but not enough to require 91 all the time.

Still worth it though.

Yes the gasket is a 3 piece assembly. There are 2 small rivets on opposite corners holding it together. Drill out the rivet carefully and the gasket is seperated.
Click to expand...

Fuzz
Which would you or have you done and what would you recommend? Extra$ for 91 not really an issue, is there a very noticeable jump going from two layers to one?
AIRBLUE
 
I'd like to know too since I'm doing this in a couple of weeks. Plus are there any downsides to removing two layers, like the engine running hotter. If the engine runs hotter, then that might be a problem for me in NFLD since we have winters here where it's 5 degrees celcius somedays and it's not cold enough to cool the sled down (like -20 degrees celcius in Ontario).

Cheers.
 
I just did this HG mod on a 600 twin, boosted the compression by about 10 psi.

I am now a little worried after reading some of these post...... I used a new Yamaha headgasket, removed the center layer, but I did not spray the gasket with ( tacky stuff???) will this be a problem and what is tacky stuff???

I realize it must be some sort of gasket glue...am I right. :2strokes:
 
Venom, you can run one on the venom it won't hurt anything, just run 91octane. Maxdlx
 
The only time a compression raise can cause damage is with pre-ignition/detonation. Using higher octane fuel is the easiest way to prevent that. Since this is the only mod it is not a problem. If your porting, changing the base gasket or already have shaved head/cylinders then it may be a problem.

The spray gasket is like an insurance policy. If you have it apart it can't hurt to spray them. I can't say what it will do without the spray. Probably nothing but make sure your torqued properly. There is a pattern in the manual to follow and there is a step-up torqueing from 9ft-lbs to 17ft-lbs.

I have 1 layer on mine. Big improvement. With the reed cage notch I had a motor that was better at every RPM.

By the way I run about 122 pounds on both cylinders @ 1300 miles past reringing 7900 miles total.
 
I did torque by the manual in the proper pattern. My compression is about 118psi on my gauge, original pistons and rings with approx. 8000 miles. Just a note I replaced the base gasket as well and the cylinders and pistons were in remarkable shape, you could still see the honing marks on the cylinders as well the pistons were totally scuff free. THAT IS YAMAHA QUALITY!!!!!!
 
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