Is there a diiference in wrist pin bushings for these engines?

We're putting one in an engine and the one that arrived was a smaller diameter. It was supposed to be the correct part.

Since I'm not familiar with these engines, I'm wondering if anyone out ther knows.


Re: Cimatti/Minarelli

gimmyjimmy /

hiya jim,

according to the minarelli manual:

stock bushing- 012 x 13mm

piston pin- 012 x 31.5 mm

hope that helps.

Re: Cimatti/Minarelli

gimmyjimmy /


I read a little deeper into that and this might be what you need:

"install new bushing, ream it out 1mm (see tech bulletin #004), and drill the three holes needed in the connecting rod to provide lubrication to the sleeve and piston pin.

NOTE: This step will require splitting of the cases in order to properly drill the bottom two holes in the connecting rod."

it doesn't come easy, does it.

Re: Cimatti/Minarelli

The dimensional data is what I really needed. I know we'll have to get it reamed, but the three holes, particularly the bottom two, are something new.

And splitting the cases?? Can't they make it any harder??

Thanks for the info gimmy.

Re: Cimatti/Minarelli

gimmyjimmy /

instead of splittin the cases, can you get an 90degree angle drill in there, or one of those flexible drill shafts that bend in different directions?


does your connecting rod already have the lube holes in it?

Re: Cimatti/Minarelli

A 90 degree drill might do it, along with a very short drill bit.

The rod does have the holes, and the original beat-to-hell bushing did also. What I don't understand is how the Vespa gets by with only one lube hole, on the top, and still works fine.

Maybe Luigi went to a different engineering school than Vinny.


Re: Cimatti/Minarelli

Dan Webber Kastner /

I had that bushing go out in my minarelli, and i am ashamed to say instead of replacing it i bought a new used engine for it. I just didnt have the tools to finish it right.


moped army

swarm and destroy

« Go to Topics — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account