152 kit

[Dale Sonnenschein]

I picked up a Saracen last spring. The owner told me it has a 152 kit. Does anyone know what they used for a head gasket?

[johnborn]

I don't think the cast iron cylinder/head combination used a head gasket.

[Larry Perkins]

John is correct in my recallection.

Larry P

[Carl Hill]

I have pistons if you need one.

[firstturn]

No head gasket if it is a cast iron cylinder.

Ron Carbaugh

[Dale Sonnenschein]

I'll have to pull it out and look again but I think I tried it with no gasket and the piston hit the head. The gasket that was on it was trimmed down from another application. It's pretty thick. Maybe 1/8 inch or so.

[Paul Danik]

Dale,

   The original 152 kits were made up using a Yamaha 305 piston, the base of the cylinder needed to be machined to lower it so as to have the correct deck height using the Yamaha piston. Also, the wrist pin in the Yamaha piston was larger than the Sachs wrist pin so an aluminum rod with a top end bushing was needed as the bushing needed reamed to fit the wrist pin.

   In time Penton had pistons made with the same size wrist pin as the Sachs piston and with the wrist pin located as to not need to machine the base of the cylinder to lower it.

   I am thinking that possibly one of the later pistons was fitted to a cylinder that had been machined to lower it, causing the piston to come up higher, which necessitated the use of the head gasket to provide piston to head clearance.

    If that is indeed the case, I would think that possibly using extra base gaskets, or a thicker custom made base gasket, might be a better solution.

   Is the rod an aluminum rod or a steel rod? If it is a steel rod you pretty much can be assured that the piston it one of the later ones that Penton had made up.

   Just my two cents worth...

Hope this helps.
Paul

[t20sl]

If using a Yamaha piston the pins that keep rings from rotating have to be relocated.

[Dennis Jones]

If the combustion chamber has not been reshaped it will need to be or the compression will be to high and difficult to tune. Nelson (3putt)on this board knows the most about that.

Dennis Jones

[Dale Sonnenschein]

Paul, I will have to take it apart and check the rod material.

Dennis, I don't know if anything was done to the chamber. I know the brother of the man that sold these bikes. He may have some knowledge about what work was done to these bikes. Unfortunately the owner of the shop passed away a while back. He was a penton dealer out of his body shop and he also sold Saracen. He did a lot of mods to bikes he sold.

[johnborn]

If I remember correctly you can see the rod through the intake port with the carb off. The aluminum rod is considerably thicker and wider than the iron rod. It is also much darker in color.

[Paul Danik]

Dale,

    On the base of the cast iron cylinders there is a part number cast into them. The one I have in front of me has the part number cast into the right side of it, which is where I think they all are, but I can't prove that fact. The part numbers are cast into the cylinder base pretty much in the center of them with pretty much an equal amount of metal above them as below.

    On the 152cc engines that have the base machined to allow for the Yamaha 305 piston to be used, there is very little if any metal below the cast in numbers. If you look closely at the cylinder base and observe if there is less metal below the cast in numbers as above, that is a good indication that the base has been machined for the Yamaha piston to be used.

   Just between you and I , I keep a magnifying glass handy for such inspections and seem to reach for it more and more as the years go by...

    The above information about the serial numbers is a handy bit of knowledge to have as you inspect prospective machines at swap meets and such. I tend to always get down and check the thickness of the cylinder base and how much "meat" is above and below those numbers when checking out a machine.

Hope this helps.

Paul