152cc sachs

[Dale Sonnenschein]

Hi everyone
I was talking with a friend about the Sachs engines today and we talked about how they were made into a 152cc. Does anyone have the story about how it was done and what parts were used? My friend and I both have Saracens that were made to the 152cc.

Thanks

[Paul Danik]

Hi Dale,

    In a nutshell, they were made using two different methods.

    The early ones were created using one piston from a 305 Yamaha. Given the location of the wristpin on those pistons the base of the Sachs cylinder needed machined to attain the correct deck height. I do believe that either one or both of the ring locating pins on the piston needed relocated as well so as the end of the ring or rings would not catch in a port. The Yamaha piston had a larger wristpin than the Sachs which meant that the top end bushing needed reamed to allow it to fit. Only the aluminum rods on the earlier engines had a bushing on the top.  The head needed some modification as well. Most of the early ones that I have seen had a Puch hi-compression head on them. Eventually Sachs came out with their own hi-compression head which was used on later ones. I don't know of any reason that a standard butch style Sachs head could not be used with the proper modifications, but most that I have seen used one of the hi-compression heads. The early ones are easy to pick out if you look at the amount of meat left on the bottom of the cylinder below and above the numbers cast in the base. Much less material below the numbers on the machined cylinders.

   In time Penton had Weisco make pistons for the 152cc conversions with the proper wristpin and ring pin locations, along with the same wristpin size as the Sachs pistons which made the conversion much simpler. The Weisco piston also allowed for engines with a needle bearing top end to be used for the conversion.

   I have seen a few of the later aluminum alloy cylinders converted to 152cc, they would most likey be used on "A" engine bottom ends, in my opinion.

   I hope this helps and if someone has more of different info please feel free to correct or add to what I remember.

   One other bit of info on the 152cc conversion that I found interesting is that George Singler had some input into the piston selection for the conversions. A person very familiar with George once told me that George was very well versed in all things Yamaha and his input really helped Penton with this endeavor.

Paul

[Dale Sonnenschein]

Thank you Paul. I knew that you would be one to explain how this was done. My Saracen came out of a small local shop that sold Pentons. The gentleman had an auto body shop and sold the Pentons on the side along with Saracen. Both him and his brother were very mechanical guys and very smart with machines. I have the brothers bike that he made into a 152. Great information.
Thanks again

[skiracer]

I saw some pistons out on EBay last week for the 152 motor....

1976 250 MC5 Original Owner
1976 Penton 175 XC

[Carl Hill]

I have a couple if anyone is interested.

[G Ellis]

Carla do you have the Weisco 152 Piston? If so I am interested

[Carl Hill]

They are Wiseco. I will measure them and let you know size.

[Dale Sonnenschein]

So my friends brother pulls out an old Penton that's been under a tarp for a lot of years. Looks to be early 70's. It's a Sachs motor with what looks like a Puch top end. Large fins cylinder and radial head. What could it be?