Oversized Wrist Pins?

[Buccaneer]

Is there a “Wrist Pins R’Us” store where a person can
order oversize wrist pins as needed?

It seems engine machine shops are few and far away
in this neck of the woods.

The little 4 hp, 1937 Viking, Opposed Twin I’m working on could
use oversized wrist pins, as the bronze rods are worn
elliptical where the pins go thru. Not a ton of meat
in the rods to bore them out and insert a bushing,
unless it was a very thin one, and then I’m not sure
what would be suitable.

I haven’t found a resource online as of yet.
Thoughts? Thanks.

Prepare to be boarded!

[Mumbles]

I had the same wear problem with my Koban rods but I did find slightly larger O. D. wrist pins and had both the rods and pistons honed to fit. Can’t remember how I found them but I probably Googled the size of the originals.

[Buccaneer]

Mumbles, it seems I have a least three options, different rods, wrist pin bushings installed
in the rod, or oversized wrist pins.

My wrist pins are .500. I Googled until I was blue in the face trying to find oversized pins
that might work, then last night I thought “metric”.

There are some 13 mm wrist pins “out there”, and the conversion tells me they about .012 oversized,
which would rid the .007 “out of round” in my worst rod.
(13mm= 0.5118110in)
Only problem is if I can find someone to perform the honing. I have some adjustable reamers,
but not sure satisfactory results would be obtained.

I’m still pursuing all three options.
I ended up ordering some rings from “Greece”…….. gave up on Dave in Pennsylvania after
trying to contact him three times.

Prepare to be boarded!

[Mumbles]

Whenever I do wristpin work, such as replacement bushings for QD rods, I take them to a local automotive machine shop to get the pins fitted to the rods. They have the Sun hone needed to get the correct fit while keeping everything properly aligned.

You must have ordered the Caber rings made in Italy. They seem to be a decent product but they take a while to arrive and the tracking seems to end once they leave Greece. I’ll be installing another set later today in a Briggs opposed twin.

[Buccaneer]

Mumbles wrote:

Whenever I do wristpin work, such as replacement bushings for QD rods, I take them to a local automotive machine shop to get the pins fitted to the rods. They have the Sun hone needed to get the correct fit while keeping everything properly aligned.

You must have ordered the Caber rings made in Italy. They seem to be a decent product but they take a while to arrive and the tracking seems to end once they leave Greece. I’ll be installing another set later today in a Briggs opposed twin.

Caber yes, but the shipping detail seemed to make me think “Greece”………
said “Greca” or something similar, but perhaps that’s a town in Italy.

https://www.dlastore.com/e_store/cylinders-pistons/individual-piston-rings.html?p=21

Prepare to be boarded!

[Author]

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