Keith Black pistons not the same size???

[screwylouie]

Screwylouie,
Cheap labor; seems that's what's it's all about worldwide these days.
Jack,
Cast flat tops. (348's)
The new .010" over pistons from UEM (Keith Black) arrived today. Everything measures even, at least with my tools. Getting my torque plates back tomorrow & I have another set of cylinders. I'm gona run with these if the bore/hone comes out mint. I might save the off set for a bike in the States where I'm close to parts & good machine shops. I'll post after some break in miles if anyones interested.

Well, I guess that answers your original question eh? First set measures questionable, second set of same part # measures ok. How long ago was it that Samuel Colt first embraced the concept of INTERCHANGEABLE PARTS? Maybe UEM needs to have a little history lesson? And they say our society is advancing? LOL!

 

[danoflhrci]

All about makin the buck. Could you imagine doing V8's all day having to check & possibly reset for each piston bore. There must have been some (EDIT) storms when they first moved their gig to Mexico.
My neighbor here gave me a baby's rocking crib to assemble cause he thought the instructions were in English. Were no instructions, only warnings not to leave your child in it unattended. Lots of them. I assembled it and would consistently collapse with weight in the right area. I took it back apart & warned him it had to go straight in the (EDIT) can. Surely something Walmart tried to pawn. See it on much larger scales all the time.
May be advancing; but, into what???????????

 

[Bryer5150]

Wow!!! I have heard of piston clearences of .0025 on older models with cast pistons, but I don't think that I have heard of a .0013 clearance before that's a new one for me.

 

[BUBBIE]

KB's are made of material that doesn't Expand much... They REQUIRE no more than .0015 Most...

signed....BUBBIE

 

[BUBBIE]

#1 post

I'm doing a 95" with KB's STD 348 Hypertuectics. The boring/honing is done (both with .0013" clearance) but I'm a little concerned about the sizes of these. One is as KB claims (3.8745) and the other is (3.8713). My rep where I bought them seems to think this is perfectly normal, but I think the freak piston should not have made it into a box for market. Wondering if their QC has over/under #'s that are tolerable. A lot of extra ring grinding on the smaller piston & I think if one was to get a piston that was larger by .0032" you would need to order an over-sized ring pack. The true piston required no grinding on the scrapers, a slight shave on the second ring & a wee bit more on the 1st to get .028".

Two questions come to mind: 1-Anyone aware of any specs KB's (United Engine & Machine) Quality Control might use? Anotherwords, maximum larger/smaller exceptable #'s before packaging. 2-Could there possibly be an issue running with one cylinder/piston .0032" smaller than the other?
Thanks in advance!!

Exactly where he should be... .001 go .0015 No GO...

You Probably saved EARLY Piston Slap...

Tight on these pistons in their bores is a MUST...

I Loved KB pistons in a build on my 2000 FXDS... Properly bored cylinder clearance (TIGHT) and correct gapping of the rings is a Needed thing.

Looks Like You are doing a GOOD job all around here.

Using the proper torquing procedures is also a must...

signed....BUBBIE

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

I TOO thought that .001 and no go fit at .0015 was Tighter than needed...

On my build using KB's....I HONED the last Little bit of clearance and believe me What a Nice Quiet running Build and get up and go....
Phhhheeeew

Just might use the KB's again.

SCARY Tight... When it's Right ,,,,, it IS a piece of art.

signed....BUBBIE