Brain fade - half shelling a .010 bearing for more clearance

[shoedoos]

Brain fade time - apologies in advance - half shelling a .010 bearing for more clearance - do I use a 0.009 or a 0.011 bearing?

[groberts101]

.011 would be adding clearance

[BillK]

.011 would be adding clearance

Not 100% sure that is correct. I believe a .011 bearing is designed for a crank that is smaller so the bearing would be thicker, giving less clearance on a .010 crank ?

[BillK]

Also wanted to add, dont forget that the thicker bearing shell goes on the load side. Upper on the rods, lower on the mains.

[modok]

if we are talking "undersize', then a .011 under bearing is thicker than a .009 under

[shoedoos]

I want to add half a thou to my existing clearance.....loosen it up (in other words......)

[groberts101]

if we are talking "undersize', then a .011 under bearing is thicker than a .009 under

Oops.. my bad.. Glen's right. The .009's will add clearance. Need to keep them consistent.. on one side or the other down the line.

Kinda funny too since I just ordered a set of coated .011's to tighten up my SBF.

[Charliesauto]

Brain fade time - apologies in advance - half shelling a .010 bearing for more clearance - do I use a 0.009 or a 0.011 bearing?

1/2 set of .009" bearings in conjunction with 1/2 set of your .010" bearings will give you approximately .0005" more clearance. We have found no issues using the thicker bearing in either side.

[gnicholson]

Thats what she said. Sorry im bored also

[ProPower engines]

Just went through the same deal.
.009 or half of the pair will increase clearance
.011 or half of the pair will reduce clearance

[modok]

Oversize bearings fit larger holes.

Shafts never get bigger, they just get smaller, But holes, holes get bigger.

So replacement parts fit oversize holes and undersized shafts.
Of course, there are exceptions, but that is how has been, In Germany and America, and probably Europe. Examples, VW, and Cat.

If you have an exception, I would be interested to see it from a source such as a bearing catalog or OE parts

I have found in the past 5 years, it is impossible to search for oversize bearings on the net, and I'm blaming YOU.

[modok]

The folks confused abut it are usually working on Japanese engines.

Does anyone know what terminology they use in Japan? I don't.

[user-23911]

It's a quiet night so I'll add my 2 cents, undersize shafts require oversize bearings.

Thanks
Randy

Hahaha.

As said, engine bearings are standard size or they're undersize to fit undersize journals.
I've never actually seen an oversize bearing but again as said....fit a bigger hole, not a smaller journal.


My own answer to getting the correct clearance is to grind the crank.
It's easy if you've got your own machine to do it.
Not so easy if you don't but at least that way you can have whatever clearance you want and can build your own frankenstein engines.
The idea is no different from buying the pistons first then boring the block to fit the pistons.
Why don't people do the cranks the same way?
Well we do ...as in WE do.

[modok]

Or bore the bearings to fit the shaft.
I still read many listed as "not resizable", even though, I don't think anybody would try anyway, these days.

oversize rod bearings are common now, for repairing "cracked" rods.

[gmrocket]

Getting to the point of being moved to advanced engine tech