Tarababusi NOS pistons - sachs motors

[pklinck]

I obtained on-line a 54.43 bore NOS Tabababusi piston for my 125 cmf, B engine penton. 3 questions;

1.) Is this piston comparable to the original Mahle in quality, etc.?  It has the L' ring on top and a compression ring.

2.) According to the Clymer manual, should we stay with the piston clearance between .00532 to .00537 when boring? Chaffer the ports?

3.)On page 41 of the binder workshop manual for the penton 100 and 125s, they mention balancing the crank assemble.  Is that an issue with the off brand pistons since the original was a mahle piston, if their weight is different?

If you have any experiences to any part of the above questions, don't hesitate to mention.  Thanks

peter klinck

[Kip Kern]

As good as a Mahle, a little beefier.  Bore them to .003. Crank was balanced if Forest built it. No worries mate![8D]

[pklinck]

Kip, Thanks for the information above.

1.) I have seen several B engine cylinders which either had CHAFFERED or un-chaffered ports.  How critical is this in terms of the rings?

2.) I looked at this NOS 54.43 Tabababusi piston later after speaking to someone and noticed on the inside it is CAST rather than FORGED. This would mean we should add a little more bore clearence (?).  Perhaps .004 thousands rather than .003 in boring setup?



peter klinck

[Kip Kern]

Chamfering all ports in all cylinders after boring is standard.  I always have Forest go .003 on my cylinders but you can go .004.  For sure on old Seizeco pistons go large!!

[pklinck]

Kip,  thanks for the info on chamfering the ports after boring.  I had to write that one down on paper in the penton workshop manual at .003.

peter klinck

[Guenther68]

The clearance for a 54.43 (red dot) or a 54,44 (white dot) is always 0,07 mm.

Best regards
Guenther Vogt,
Hercules Club, Germany



******************************
Hercules-Interessengemeinschaft e.V.
URL: http://www.herculesig.de

******************************