Con rod kit

[Lew Mayer]

Anyone out there know where I can get a line on a con rod kit for a 125A motor?

Lew Mayer

[3putt]

Lew, if you find 2 please let me know where I can get one please.  wnm

wnm

[john durrill]

Lew,
 You should be able to get them from the Hammers in Germany. We have used them in the past and they are reliable. They took Pay Pal with our last transaction. They handle spares for the Sachs military 125's .
 Here is their web site and contact info.
http://www.motorrad-klassiker-ersatzteile.de/html_eng/index.htm
 You can use a B rod kit but the pin would need to be shortnd a bit.
Hope this is some help.
John D.

[firstturn]

John,
  What is the exact differences in the A and B pin length in MM.  Thanks.

Ron Carbaugh

[john durrill]

Ron,
 its either 1 or 2 mm. ill see if i can measure one tonight. Its enough  that you can have some clearance issues in some engines.
 the B rod i had installed ( A euro rod B engine kit) for the 175 conversion had to be trimmed i remember.
John D.

[john durrill]

Ron,
 I went home for lunch. The A rod pin we have measures 2.140
The B rod pin we have measures 2.205.
Did that help? I don't remember how much Falcon had to trim off my Euro Rod kit.
John D.

[firstturn]

Thanks John.  I had just never measured them because I never had the two different rod kits at one time.  I will keep this for future reference.

Ron Carbaugh

[OUCWBOY]

Ron,
Check with Doug W. I think he had to install an "A" Rod into a "B" engine he did for me. I think he told me he had to shave some of the rod to clear the engine cases.


Donny Smith

[firstturn]

Oucwboy & Everyone,
  Before this gets out of hand let me explain.  Donny(Oucwboy) you need to check with Doug to see what he did with what.  
1.  The Pin(big end bearing for the connecting rod) for the "B" style Sachs engine is longer than the "A" pin.
2.  I have two "B" engines with "A' pins in them.  I have run one and had no problems.  I haven't nor has anyone else raced that engine.  
3.  In my opinion all you do is loose some stuffing effect when you have space left in the bottom crank case from the shorter pin.
 
  Again, I am not an expert and this is just my opinion.  Any thing I have missed please chime in.

Ron Carbaugh

[john durrill]

Ron,
 B rod kits ( at least NOS kits ) were Ground down in a radius. You can see the area, its the out side of big end , both sides of center.
 The B crank is smaller in diameter, the rod pin hole sets closer to the crank's slab edge and the cases for a B engine are stuffed with an inner ring. The A NOS rods would hit a few degrees on either side of and at bottom of the stroke.
 B rod kits will work in an A motor as long as the big end pin dosen't come too close to the sides of the crank case when the side clearance on the rod is set ( .011 to .018). The .002 to .005 end play in the crank (which can grow over time to .007 or beter) and differences in pin length(.065 in the ones i measured) can add up to a problem on some cases. Plus you could streach the hole a bit the rod pin resides in( the pin and hole are tapered)
 A rod kits can be used in a B motor if you can live with the rod pin not extending out to the edges of the crank slabs (the rod pin  is tapered where it contacts the crank slab so you loose some grip) and you radius the outside of the big end of the rod enough to clear the crank cases at the bottom of the stroke.
 I hope Doug chimes in here. He has messed with a lot more than we have . My experance is limited to just 3 Sachs cranks in the last 3 years and what we did in the shop in the early to mid 70's. He can explain thing like this a lot better than i can chuckle chuckle!!!
Did this help any guys?
John D.

[Doug Wilford]

Chime, chime  What you are doing using "B" rod pins in "A" cranks,  I did once, it was the first time I found out there was a difference in pin length.   My suggestion is to have the B pin equaly ground on each end to meet the correct length of the A pin and then you can press everything together at flush and it will work.   Just remember that the rod pin is tapered on both ends.   You cannot push the pin throuugh the slab, the slab must be removed from the pin.    Have fun!

[Lew Mayer]

Thanks for the help, Guys. All info duly noted.

Lew Mayer