Planet Minis

johnson05

For the first time I just took apart my engine with the kitaco big bore kit. The head gasket does not even remotely fit properly. Has anyone else out there with this kit had the same problem? If so what have been the common fixes?

zwieblekopf

wrong section....

NCNSR

The Kitaco gasket is crap it is the same type as on my Malossi kit (Thick asbestos type material),I bought a 2004 NSR50R(One Ply) Thin Gasket and a 1990 NS50F(Three Ply) Thick gasket from Honda and had the machinist who worked on the cylinder cut both to match the 46.3mm Bore........The Autoboy Kit came with a 2004 NSR50R (Thin) gasket cut to match the 47mm Bore.....I think most people dont use the Kitaco gasket because of leakage problems.........As i remeber it most people chuck the gaskets and use Honda gaskets.You could use a 2004 and raise your compression or get the NS50F #12251-GE2-013 gasket which is similar in thickness to your current gasket............

fireman_343

Yep... what NCNSR said... everyone that I know that has the kitaco kits on their 2 stroke NSR's, use the stock head gasket cut to match the bore.

Buy a few gaskets and have them all cut, so when you do maintenance on the motor, you can swap in a fresh one without having to wait to get it cut.

best of luck to ya!

johnson05

I thought about cutting the stock ones. I have a few laying around. First off though I'm going to try using an o-ring ala TZ cylinders. I have another kitaco cylinder on the way so if that does not work I'll go with the cut stock gaskets.

Jeff Lebowski

Does this mean you are going to machine a land into the cylinder? However you do it please post your results.

johnson05

Here is a pic of my cylinder and head. Head turned out @ 5.5cc and squish is .85mm. The outer edge (water/coolant side) is sealed by just cutting the inside out of a stock head gasket.

Jeff Lebowski

I love it! How has it worked out so far?

johnson05

The waterside sealed flawless. The oring sealed the combustion side good but my piston and ring are pooched so I probably won't be running it for an extended period of time until spring. I was going to go in for one last set of dyno runs but the ring would only give me 90psi compression. Those pistons are on back order so when I get a new one I'll heat cycle the engine a couple of times and see what I get for compression at that time.