JCC Piston oil ring width - Narrow or wide

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Madnorton

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Someone will know the answer. I have just removed the barrel from a bike that had a 40 a day habit, in fact smoking would have been ideal - it would have given oil pumps in Texas a run for their money!! What I noticed when I pulled the barrel was that the left hand 3 piece oil control ring had half the lower ring located in with the top ring with both ends of the lower ring still sat in below the expander.
There is no damage to the bore, still showing hone marks, and the pistons are in good condition. With the oil control ring removed it seems that the groove depth would accept a wide oil control ring. I believe the pistons (0.020'') and the rings date from 1992 and the bike was once located in the US and is now back in the UK. This will be one very lovely very early 'S' type when running correctly.
Compression was good, but it pumped some oil until the extent it would foul the plugs and die! something suggest to me that the oil control rings are inocrrect - does anyone know on what the JCC pistons should have, wide or narrow?

Many thanks,
 
This is probably not the answer to your question but, when I rebored my bike a couple of years ago I had heard (maybe wrongly) that JCC pistons were good, but the supplied rings were crap, so I fitted the JCC pistons with NOS Hepolite rings and the job turned out just fine, no smoking, reasonable oil consumption etc etc.
sam
 
trident sam said:
This is probably not the answer to your question but, when I rebored my bike a couple of years ago I had heard (maybe wrongly) that JCC pistons were good, but the supplied rings were crap, so I fitted the JCC pistons with NOS Hepolite rings and the job turned out just fine, no smoking, reasonable oil consumption etc etc.
sam
Click to expand...

I have heard same info .... toss the supplied rings and use Hastings or Hepolite.

Slick
 
Nothing to add on the rings but I would take a close look at the barrel condition. You will want to glaze bust for the new rings so I suggest that maybe a light initial honing might reveal any cylinder wall irregularities, then see what it will take to clean up. Doubt there will be any issues but worth a close look before committing to a particular course of action.

Also have a close look at the condition of the oil ring grooves for damage. I am speculating here that the quality of the ring lands on the oil ring grooves is probably not as critical as on the compression or second rings but it is worth having a close look if you have not already done so.

So you repatriated the bike. Pictures would be good if you get a chance.
 
A quick measure on a stuffed piston was 4mm wide
Nothing wrong with the JCC rings , simple and basic, as with all rings they need to be checked before fitting, as do the JCC circlips, some were loose
 
Many thanks for the replies - I now have the answers but stuffed for rings. I have tried an NOS AE set with a 3 piece ring, not a good fit, also the Gandini 2 piece rings, again it seems that the JCC piston oil control groove is slightly narrower than the Gandini. So it has to be the Hastings rings which are known fit on JCC pistons. The hard part is where can I buy a set of 750 +0.020'' with the wide oil control rings? I will need to order these in from the states as it seems no one here in the UK sells them.

The bike being a '69 has had at sometime new 750 +0.020'' fitted, but when the rings where bought they specified rings for a '69 bike and thus narrow rings that were totally ineffective.
 
I've dropped them a request, see what I get back on Monday. If they can't supply it won't be any hassle getting them from the states.
 
If the grooves to narrow get it turned out to suit the rings available, small cheap job, I do remember that some of the Italian pistons had different groove diamensions but the JCC ones should be an exact copy of the AE originals, although yours are older maybe quality control had been implemented then
 
And quick as a flash, no reply from the UK agent, not even an acknowledgement - so I need a link to someone who stocks them in the states.

Many thanks,
 
Not sure they are, Wassels Hepolites sold by most UK outlets advise or do not sell them with the rings they come from the factory with, might have been a while back not anymore it seems.
 
if the pistons / rings are supplied in yellow black Hepolite packaging they will be Hastings rings and have been for several years

some dealers are selling JCC pistons with Taiwn rings they will be supplied in non branded packaging

the Hepolite pistons with Hastings rings for Norton are very good i have fitted several sets and much prefer them to GPM
 
As I do not remember anyone mentioning the subject then just to confuse I will......Piston rings are measured by bore size, width AND maximum radial thickness or piston groove depth(along with type /material).
Example. For Hepolite / Wellworthy pistons..... A Triuumph std 500 compression ring has a bore of 70 mm and a ring width of 1/16 inch but the maximum radial thickness or piston groove depth is 0.100 inch. A Dommy +40 compression ring will also be for a 70mm bore and 1/16 inch ring width but the maximum radial thickness or piston groove depth is 0.109 inch. Fit a Triumph compression ring into the Norton piston and I suspect it will not seal correctly as compression rings require gas pressure behind the ring to force it on top the bore to seal correctly and if the gap between the bottom of the ring groove and back of the ring is not correct I suspect the ring does not seal correctly.
OOPS... have just noticed that BSA A10 69.990 mm bore 1/16 width compression rings for the original BSA piston and varios Hepolite pistons employed rings with a maximim radial thickness of 0.120 inch while those for the Hepolite 15638 piston were 0.112 inch.....
Of course pistons manufactured these days for our Nortons could well employ metric size rings.....
Never did learn how one selected the correct exspander for those 3 piece oil control rings.....especially as they were not only used on Nortons .......
 
Madnorton said:
Not sure they are, Wassels Hepolites sold by most UK outlets advise or do not sell them with the rings they come from the factory with, might have been a while back not anymore it seems.
Click to expand...

JCC pistons for British bikes were available (as 'Emgo' etc.) well before Wassell began to sell them as (new) 'Hepolite', and as I understand it, it's the non-Wassell JCC pistons are the ones that have poor quality rings.

The piston rings distributed by Wassel (either as ring sets or with pistons) and sold under the 'Hepolite' banner are made by Hastings as far as I'm aware.
 
Madnorton said:
Compression was good, but it pumped some oil until the extent it would foul the plugs and die! something suggest to me that the oil control rings are inocrrect - does anyone know on what the JCC pistons should have, wide or narrow?
Many thanks,
Click to expand...

I do not think that it is a matter of narrow or wide but depth of the groove in the piston.
My Hepolite grooves measure,
.125 for the compression rings
.177 for the oil rings.

Other manufactured are not as deep and should be avoided. IMO
Needless to say, which ever pistons you have/use, the rings need to match the pistons.
 
L.A.B. said:
and as I understand it, it's the non-Wassell JCC pistons are the ones that have poor quality rings.
Click to expand...


And were does this bullshit imformation come from, I'd fit a Taiwanese ring set before I fitted a Hastings ring set
 
splatt said:
L.A.B. said:
and as I understand it, it's the non-Wassell JCC pistons are the ones that have poor quality rings.
Click to expand...


And were does this bullshit imformation come from, I'd fit a Taiwanese ring set before I fitted a Hastings ring set
Click to expand...



soft-seize-t20249-30.html#p261870

comnoz said:
For a street bike I would use JCC brand pistons. They are sold by Emgo and others. They are so cheap one would think they are no good but they seem to be every bit as good as the Hepolites. I would not use the JCC rings [use Hastings, Total seal or OEM].
Click to expand...


http://www.britbike.com/forums/ubbthrea ... Post421395
John Healy said:
JCC private labels pistons for numerous suppliers in the trade.

Originally, some 25 years ago, the only source was Carfel, when they were based in Miami. Later Emgo, a Carfel competitor, began importing under their brand name. Harris private labeled them in the 1990's and JRC and Coventry import and sell them under the JCC brand.

JCC supplies pistons with or without rings and it is common for them to be sold bare with the dealer selecting the brand of ring. While the pistons will all be the same the brand of ring varies depending upon who distributes them.
Click to expand...
 
So the bad ring reputation more than likely comes from the fact that they AREN'T JCC ring sets supplied with the pistons but some reseller weasel that doesn't want to pay the money for a Taiwanese ring set and supplies some other cheap inferior shit that then gets blamed on the piston manufacturer
 
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