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[timtoolman]

local shop "deglazed"  106 s&s cylinders after a oil control ring problem with a hand hone. i think they took to much material, now top comp ring gap is 22.5. on  both cylinders  s&s reccomends  max gap is 22.  what should i do!!!!!.  target gap is .17  range is .12  to .22.  would it be ok at 22.5??    the rest of the rings are ok  only the top ones on both cylinders

[timtoolman]

oops  thats piston ring gap to big .  sorry

[Twolanerider]

Cylinders already been re-honed anyway.  With a fresh hone why re-use old rings?

Set of rings doesn't cost much (relative to the effort of opening the engine back up).  So why even consider taking a chance?

[timtoolman]

these are new rings i got today

[timtoolman]

should i get them rebored to 107  cu   or will they be okas  is ,  or can any one tell me  do i need  oversized rings and file them to fit  and where can i get them if i need to

[Twolanerider]

these are new rings i got today

Didn't realize that.  Sorry.  Should have read more carefully. 

Honestly before putting any particular cart before the horse and buying more parts you may or may not wish to use it's time to stop.  If was assume the rings were in the middle of spec before (perhaps not a safe assumption but you've got to start somewhere) this could suggest someone honed the cylinders "significantly."  Get someone with a set of micrometers and measure the holes.  

Don't measure them just in one position at the top either.  Check around the diameter of the hole to make sure it's round.  Also check down deeper in the hole to see if it's consistent top to bottom.  

Unfortunately the only thing known for sure right now is that not enough is known for sure to know what to do.  As you suggest, however, it's at least conceivable you could be looking at actually cutting larger to get to a next standard oversize to make the holes good again.  That of course means pistons and rings.  As much as that might suck this isn't a task you want to cut corners on.

Sorry for the hassles man.  Find out for sure more of what you've got and check back in.

[timtoolman]

thaks  im thinking i need a cut and bigger rings and piston,,  this project hassnt been fun.  i have  a 103 in now but i want my 106 cyls back.  ive measured in different locations in the cylinder,  its the same

[Twolanerider]

thaks  im thinking i need a cut and bigger rings and piston,,  this project hassnt been fun.  i have  a 103 in now but i want my 106 cyls back.  ive measured in different locations in the cylinder,  its the same

You're skirting the edges.  Perhaps not of what a ring might seal in (if the hole is good and round) but obviously of what you're comfortable with.  Exercise a little patience, take the proverbial extra breath necessary to sometimes decide just how you wish to proceed and make the engine safe and sound.  A pair of pistons, a set of rings and a little machining isn't necessarily chump change.  But it's still a heluva lot better than doing it all a second or third time.

Good luck .

[HD Street Performance]

should i get them rebored to 107  cu   or will they be okas  is

Don't know
I suggest putting the barrel in a torque plate and checking piston to skirt clearance before zeroing in on the rings. The rings can be fixed easy enough but first what is your piston clearance and is the bore true and properly sized?

[timtoolman]

thanks for the reply  the original cross hatch is still visible so i dont think too much was honed out..  i measured the cyl to piston clearance  and its within s&s specs,  the one spec speet that comes with the kit says top ring gap can be.16-.22 on 31/2" bores but   all other bores.16  to.24  i have a 3.927  bore as u know.  but the other spec sheet that came  with it says .16-.22.  Id just feel better if i could get the ring gap at .17-.20 like it used to be  or smaller than 22.5.  What do u suggest for the ring  fix since thats the easier  part as you replied in the previous post     Im just not comfortable at being.5 over max gap setting  and was thing about ring life  maybe im worried for nothing what do you think???     :-\thanks

[HD Street Performance]

Rings can usually be found in .005" over the bore and file fit but these S&S may be the exception. I think they have an odd top ring thickness not 1.5mm or 1/16". They are also not conventional material which is typically cast iron or ductile iron to name a few, these may be stainless (top ring) IIRC and if they haven't changed.
You will have a lot better luck calling their tech line and asking them what to do.

FWIW the .022 is just a head problem for you not one that will actually cause either excessive blowby or oil consumption assuming the bore is right which I already detailed.

Ball honing does not remove appreciable material and is just a glaze breaker to give the rings a new surface to break in and seal properly.

[timtoolman]

i also thought a ball hone shouldnt remove that much material in just 30 sec.   your right it is a head thing with me on the .023 top ring gap.  the middle is .016  i havent  gapped it yet. it should be bigger than the top gap (according to the s&s inst)  i will make it .024  its still in specs.  so i think the piston to cyl gap is good too.  i do have a email to brent at s&s .  hope it does work though

[hogasm]

Dewey has given you some good advice.

Make sure that the cylinders are round while bolted into torque plates

Make sure the tolerances of the piston skirt/cylinder wall is within spec for your pistons

Piston ring gap was always taught to me as .0045 per inch of cylinder tight motor----.0045 x 3.927 = .01767"
                                                                                                               loose motor---.0055 x 3.927 = .021598"

Since going this far don't skimp...do it right

[timtoolman]

ill  probably get  set of cyls bored out to 3.927  i have 2 sets.  already have the 106 pistons and  new rings,  be cheaper that way. my buddy want my  out of  spec s&s cylinders for a 107  build he will be doings.  just cant figure how a real quick 30 sec deglazing hone screwed them up that quick

[Twolanerider]

ill  probably get  set of cyls bored out to 3.927  i have 2 sets.  already have the 106 pistons and  new rings,  be cheaper that way. my buddy want my  out of  spec s&s cylinders for a 107  build he will be doings.  just cant figure how a real quick 30 sec deglazing hone screwed them up that quick

If it was just 30 seconds with a ball hone it didn't.  Either not right at previous assembly or some wicked wear in service.