125 engine case stamp/year?

[Scott Summey]

Totally new to the Vintage off road arena so pardon my ignorance but what I believed to of purchased was a 72 CMF Six Day (frame numbers match)  from one of the POG members. This is my first Penton and first two stroke dirt bike. While sorting it out I noticed that it had been apparently upgraded with a Motoplate ignition. Once running and shifting through the gears lo and behold it turned out to be a six speed. To me this story is getting better all the time.

Today while putting in a new clutch cable (thanks Al) I noticed the number 74 stamped on both bottom cases. My Question, is it customary for Sachs engines to be stamped on the bottom cases with the year model?

Also I hope to use this bike later this fall/winter to make an attempt at vintage racing. Any suggestions on set up would be appreciated. Thanks.

[brian kirby]

A '72 could have had points and a 5 speed or Motoplat and a 6 speed depending on when in the year it was made. My '72 100 is a 6 speed with a Motoplat, but I replaced it with a PVL.

Brian

[Lew Mayer]

I don't think it is a year stamp but a stamp to show the case halves are matched.

Lew Mayer

[Ernie Phillips]

Scott,  Welcome to the POG.

Race set-up:  A stock Sachs motor is plenty powerful.  Focus on getting the carb spot-on and learn how to shift.  A new needle/needle jet is a good idea.  The Sachs motor has good mid-range but won't lug like a SL125 so having clean carburetion is a must.  The early Motoplat is not too reliable ... a PVL might be in your future.  If you are serious about racing go ahead and get the PVL and forget about ever having a dead ignition.   Then, spend your extra money on quality shocks and good tires.   Since you are new to two-strokes, you might want to run lower gearing until you get used to the power band.   13/60 is a good ratio.   I prefer o-ring chains, EK 428-132 links.  Use the chain guide block for early Jackpiner.  And don't forget, "You don't breed race horses at the race track."  (ie.  Don't be a dummy - - sort your bike out at home – R. Carbaugh to EP circa 2007)


Ernie P.
Chattanooga, TN

[Scott Summey]

Ernie,Lew Brian,

Thank you for the info on the bike. I've been working on the carb and have put everything back to stock specs to get a baseline. Most of the other work has been replacement of all cables and fluids, kill switch  and a good general cleaning and painting of the frame. I put a basic set of Progressives on for now and just picked up new sprockets from Al. I also have acquired a spare set of wheels and plan to put together some alloys when I have some time.



72 Six Day
Jax, FL