Piston ring identification

[GrumpyUnk]

 I have a set of rings for a 'big' bore 44mm piston that have marks, but I don't understand the marks.

 The first shows the whole set, the second peekshure shows the two compression rings, and the markings.

 I have contacted the vendor, but they are clueless, and have referred me to what appears to be a copy of a post from this site.(looks like they used the whole post), and sent me a picture of how the rings are installed.

 Can anyone tell me what the marks mean?  If not, I figure the top ring has one mark, the second ring has two.  But there is a "T" marking on the one with two symbols????  There is no 'color' difference between the two rings, and I cannot see any sort of bevel to indicate.

thanks
tom









and the two compression ring(maybe.  )




 My posting is nicht gut.

[Happypancake!]

Are they for a 4 stroke ?

[90GTVert]

Lots of sellers know nothing about what the sell, and they've been using my BBK how-to since just after I put it up. Not sure why they can't link to it instead of re-upping it, but that's another issue.

The one with the "T" should go up top.

[GrumpyUnk]

Apparently copied in whole?:

Message from 3rd party seller:
hello， this website showing how to install
ebay.globaldc.com/scooterparts/borekits/100ccGY6/install/bbk.html

any question ,pls let me know

..................

Ayup, copied the whole page, complete with pics. And... the web info on the left side... At least the links still point to this site, more or less.

Thanks for the replies. It is a 4T, if you looked, the first picture showed an oil control ring set in addition to the two compression rings. I guess you'd have to click on it and make it big to really see. The separator and two oil control scraper rings are used only on 4T cylinders to my knowledge.

After posting, I wondered, did the "T" matter? or was it the number of symbols?

tom

[90GTVert]

Here's a link to that on this site, updated since they copied and pasted it years ago and including a pic from a manual that shows a T on the top ring. Don't tell the eBay sellers about it though. lol

www.49ccscoot.com/bbk.html

[knobby]

Welcome to the club.. copied products, copied product instructions too.

[GrumpyUnk]

A few comments about the BBK install piece.

All the piston rings I have installed, for longer than I want to admit and hardly believe, have been installed in the order of oil control 'ring' or 3-piece combination, the second compression ring, and finally the top compression ring. I find it more difficult to slip one ring past another, and the distance from the bottom to the lowest groove is much longer than from the piston crown downward. It made sense to go 'bottom to top', and I think I got the sequence from instructions on the first set I ever installed.
Some seem to have a question about the oil ring separator. "Should the ends be overlapped or abutted?" being the point in question at least on another scooter web site. Some ring manufacturers have gone to the point of painting the ends of the separator to make the ends obvious so they are not installed with the ends overlapping. They must be abutted on installation. The Chinese makers don't bother with that, barely bothering to mark the rings as noted by my question above.
Some seem to be concerned about installing the wrist pin circlips such that the 'mass' of the circlip 'straight'
portion is not subject to acceleration, so they 'clock' it to minimize the 'free' mass. The straight section being pointed straight up and down, parallel to the cylinder wall so it is supported when the piston accelerates back and forth.
To add one point, about ring break-in. Years ago I read the instructions for the rings, and their recommendations. The idea was that rings were very firmly pushed against the cylinder walls when new, with more than normal friction. To get the rings to seat quickly, without over-heating them due to the friction, ten runs of hard acceleration were done. More or less, get the vehicle in 3rd(top) gear going about 30mph. Floor the gas pedal, but not enough to make an automatic transmission downshift. The idea was that there would be max cylinder pressure generated, the gas pressure generated in the cylinder being maximized, which would get behind the piston rings and press them firmly against the cylinder wall, but at the same time not increasing rpm such that friction would be significantly increased. After flooring the gas, accelerate from 30 to about 50-55mph, and then back off the gas completely. Doing so would increase the vacuum in the intake manifold, and in theory, cause more oil to be sucked up past the rings as the vehicle slowed down. Repeat about 9 more times. After that, don't run continuously at the same rpm for lengthy periods of time, vary speed, and back off the throttle, slowing down from cruise about 20 mph or so.
I can only report my experience, and the new car I bought years ago has reached 250k miles without doing anything to the head, valves or reciprocating parts. It may burn a quart of oil in about 2,000 miles, it might be 4k, but I don't add between changes. I broke it in driving cross country from Indianapolis, IN, to Dublin, CA using the 'vary the speed, and back off now and again' method.
 The last comment is about the timing chain which seems to elude control by all the BBK installers I have viewed on youtube.  I think adding a piece of 'mechanics wire' to keep the chain from slipping into the sump might be a good idea.  Use of a thin, longish 'zip tie' to do the same function is an alternative.
 I am not trying to criticize the work, which I think is excellent, just conveying some of the 'stuff' I have learned through 50 years of experience working on ICE piston engines.  Please take no offense, as none is intended.
Long winded and off topic, but maybe someone finds it interesting.
tom