To helicoil or not to helicoil...(cam caps)

George and Skyman,
you know, the 8mm bolt is real common for all of the dragracers apparently, as I read multiple postings on the dragbike forum.
I really think that this is probably the best way to go if you take it apart alot.
If not, you might only need to do it when needed. I did do it on one hole.. it does look odd a bit, big holes!
The other thing about all of this is I now torque down to about 86 inch pounds, not the 108 reccomended by the shop manual. (I wonder if that should be different for the 8mm..
I also used a 1 pitch..
It has never stripped another bolt, and they have all stayed at that torque...
FYI

thought i would bump this too, well its been 4 years, and with all of the cam bolts at 90 inch/lbs instead of the 108, all of the bolts have stayed put, right on at what i torqued them at. have been apart many times since, so it seems like the 90 inch-lbs will be SOP for me from now on. maybe this might end one of those constant issues,,,stripped cam bolts...

On my GPz1150 I am running .420 lift cams and APE springs. I have decided at the very beginning that shim under bucket is a waste of time and effort. I take the engine well past 10k quite often and had never had a problem with the shims. some people due the shim under bucket because of less weight. I just handled that with titanium retainers. i also bought a M6 Helicoil kit for those bolts with 12mm long inserts. As I might feel on that is not right I just do all four on that cap. Why put so much effort into something just to shlock off something els. That just makes no sense to me.

It's all in how the cams are installed that prevents the the threads from pulling out. The service manual method is the worst way believe it or not.

auggiedog wrote:

thought i would bump this too, well its been 4 years, and with all of the cam bolts at 90 inch/lbs instead of the 108, all of the bolts have stayed put, right on at what i torqued them at. have been apart many times since, so it seems like the 90 inch-lbs will be SOP for me from now on. maybe this might end one of those constant issues,,,stripped cam bolts...

I'm not one bit surprised. I've used the 5mm longer bolt trick lots of times. Never had a bad result

If Kawasaki would have done that from the factory and corrected their installation procedure this would be a non issue.

larrycavan wrote:

auggiedog wrote:

thought i would bump this too, well its been 4 years, and with all of the cam bolts at 90 inch/lbs instead of the 108, all of the bolts have stayed put, right on at what i torqued them at. have been apart many times since, so it seems like the 90 inch-lbs will be SOP for me from now on. maybe this might end one of those constant issues,,,stripped cam bolts...

I'm not one bit surprised. I've used the 5mm longer bolt trick lots of times. Never had a bad result

If Kawasaki would have done that from the factory and corrected their installation procedure this would be a non issue.

So Larry...would you mind explaining the method that you use?

He crushes up BS34 carbs,melts them down ,and pours the liquid metal in the hole and sticks any old bolt down in there .Holds great--but u cant get the thing out--ever.bj

Actually, the extra length bolts are one thing, and sort of a last resort sort of thing....
But what was remarkable to me is the fact that torquing the bolts to a lower than specified 108 inch-lbs seems to be a more correct torque setting.
It would be my guess that all of the stripped cam cap bolts are because the 108 is really just too tight for the reciever in the head. combine that with a 30 year old bike, and the fact that not everybody has the feel it takes to sense when a bolt is on the edge.....
I think that if more folks worked with the 90 inch-lbs and a good torque wrench, you can say goodbye to stripped bolts in the future.
I too have had the bike over 10k many times, and even missed a shift or two before the rev limiter, still all strong.
Any thoughts?

I would also like to revist the discussion of drilling these all out to 8mm.....
has any one done this, more than once? And how did it work?
when I tried it it see,ed like there was not a great deal of metal left in the cam cap hole....
see the above post by Wired george

Not sure how Larry does it, but I try and install the cam caps as evenly as possible. The first time I started to reinstall the caps and the FSM said to install the inboard left caps first, I saw how canted the screws were going in...stopped, and installed all the caps on the cam. I work each bolt a little at a time so the cap is parallel to the head. The first time I did it I was worried about the cam lining up correctly, so just before it starts to make contact with the head, I tap the cam slightly with a rubber mallet to make sure it's set in its alignment slot. I'm also a proponent of 90 in-lbs.

In all the earlier KZ900/1000 FSMs they were listed at 104 lb/in (8.67lb/ft). In the later books it is listed as the outrageous 12lb/ft. I have no idea why they changed it. i have always used 100 in/lb until one time that I attempted the 12 lb/ft (144 lb/in), at which time I had to buy a Helicoil kit.

larrycavan wrote:

It's all in how the cams are installed that prevents the the threads from pulling out. The service manual method is the worst way believe it or not.

YES, I agree, 100%!