Author Topic: Piston rings problem  (Read 1277 times)

Offline Frenchy

  • A's Good Friend
  • ***
  • Join Date: Oct 2009
  • Posts: 66
  • Karma: 0
  • 1957 A7
Piston rings problem
« on: 26.07. 2010 16:30 »
I found a set of new old stock rings.  The problem is that even though they've never been used, they're so old that the writing on the rings is gone.  The "T" or "top" that is usually written on them is no where to be found.  I've used a magnifying glass and can't find it!  How do I find out which way is right side up?  The rings I'm replacing are clearly marked, so I've tried lining them up and looking for a taper, but I can't see anything.  The top rings seem to be slightly rounded on top and sharper on the bottom of the ring, so I think I've got that one under control.  The oil ring didn't say that it needs to be right side up on the package (top and middle did say that they need to be top side up), so I think that one's fine.  It's the middle ring mostly that I can't figure out. 
1957 A7 bobber, swing arm
Columbus, Ohio, US

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5720
  • Karma: 66
Re: Piston rings problem
« Reply #1 on: 26.07. 2010 16:54 »
not all rings are marked Frenchy and not all sets have tapered ones either.
The set I just used was (I hope) with out marking re top or any taper, ( I did look closely at the rings ), on the other hand the ones I put in some ten years ago did have a taper which I am pretty sure I got right, I think probably oil consumption would be a factor if you got them wrong.
Others with more knowledge and better eyes might like to put you and me right on this one
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Online groily

  • Wise & Enlightened
  • *
  • Join Date: Jul 2007
  • Posts: 1841
  • Karma: 31
    • www.brightsparkmagnetos.com
Re: Piston rings problem
« Reply #2 on: 26.07. 2010 22:59 »
Don't reckon age alone will remove the word TOP - if nothing's visible, then probably they're parallel and no problem as to which way up they go. I've loads of rings of various ages and mileages all over the place, and with a strong glass I can make out the TOP marking on all rings that originally had it even after mega-miles. On NOS ones, it should be very clear if there's any marking on them.
AFAIK oil-control rings aren't an issue.
Agree with bill re oil consumption telling you if you put tapered ones in the wrong way up!
Bill

Offline BSA_54A10

  • Wise & Enlightened
  • *
  • Join Date: May 2008
  • Posts: 2544
  • Karma: 37
    • BSA National
Re: Piston rings problem
« Reply #3 on: 27.07. 2010 11:40 »
http://www.totalseal.com/TechPage.aspx#trGaplessPistRings
Go here and read the tech pages, all you want to know about fitting rings
Bike Beesa
Trevor

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5720
  • Karma: 66
Re: Piston rings problem
« Reply #4 on: 27.07. 2010 12:55 »
Nice link Trev - bookmarked to "bike info"
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline Frenchy

  • A's Good Friend
  • ***
  • Join Date: Oct 2009
  • Posts: 66
  • Karma: 0
  • 1957 A7
Re: Piston rings problem
« Reply #5 on: 27.07. 2010 14:45 »
Thanks for the help.  I'm just going to assume that they're parallel (despite the packaging instructing otherwise.)
1957 A7 bobber, swing arm
Columbus, Ohio, US