Author Topic: New Rings  (Read 5595 times)

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Offline monte34

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New Rings
« on: May 28, 2016, 11:05:35 pm »
I'm looking for a set of rings to suit a Carabela 200. They're 65mm standard pinned ring on the lower and L profile on the top ring. Is there an outlet I can contact to see if there is something that will fit, piston as well would be good but I don't like my chances.
Any help appreciated....
Rob

Offline Suzuki Brother

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Re: New Rings
« Reply #1 on: May 29, 2016, 10:49:57 pm »
Wiseco used an L-profile top ring on some of their 2-stroke pistons the 70's.  They don't make L-profile rings any more but there's still old stock around.  I recently bought a NOS Wiseco piston kit for a '76 RM250A with a 70mm bore & the kit uses an L-profile top ring.  Someone is selling the exact same NOS piston kit on eBay at the moment with a good photo:
http://www.ebay.com.au/itm/140741941133
The Wiseco P/N for the rings in the kit is 2756LCS.  The 2756 stands for the bore diameter in inches (i.e. 2.756" or 70.00mm) and I think the L stands for L-profile top ring, not sure what the c & s stands for.  Anyhow, maybe Wiseco produced L-profile rings for a 65mm bore at some time, presumably the P/N would start with 2559 and have an L after it.  I have no idea whether they were actually made, but it might be worth chasing.  For instance after noodling around on eBay for a bit I found this NOS Wiseco piston kit with L-profile top ring for an old 175 Yammie:
http://www.ebay.com.au/itm/191504860807
The piston is stamped 60 thou (or 1.5mm) O/S & going by the ring kit P/N of 2658LC the bore diameter is 67.5mm.  So the rings for the standard bore Wiseco piston kit for this bike are getting pretty close to what you're after.

I suggest you contact someone who's sold Wiseco pistons for a long time & see if they can match up a set of old stock Wiseco L-profile rings.  If you're in Melbourne you could try Ken Colvin in Heidelberg.  Even if he doesn't have them perhaps he could give you some old Wiseco P/N's that you could then search for online.
Good Luck with it.

Offline Freakshow

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Re: New Rings
« Reply #2 on: May 30, 2016, 03:21:41 pm »
i HAVE A BUNCH OFF OLD 'L' type yamaha rings etc.  Is the 65mm measure across the Diameter ?  you can cut them down to suit if there over.
74 Yamaha YZ's - 75 Yamaha YZ's
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For sale -  PRE 75 Yamaha MX stuff, frame, motors and parts also some YAM DT1,2,A and Suzi TS bikes and stuff

Offline monte34

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Re: New Rings
« Reply #3 on: May 30, 2016, 11:15:30 pm »
The standard piston I have is 65mm diameter, the motor is a Minarelli design made in Italy and used in several different brands under license.
There is one set of rings on Ebay to suit this motor, but they are 66mm (2nd oversize). Wouldn't that be too great a difference to cut down
to suit the 65mm piston, approx 3.14 mm, anyone have an opinion?
I have been told of a couple of places to try including Ken Colvin, thanks for the help.

HeavenVMX

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Re: New Rings
« Reply #4 on: May 31, 2016, 01:16:26 am »
The 'L' profile rings is commonly know as a Dykes Ring.
« Last Edit: June 01, 2016, 04:47:59 pm by HeavenVMX »

Offline Mick D

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Re: New Rings
« Reply #5 on: May 31, 2016, 11:39:56 am »
Hi Rob, I wouldn't have any hesitation to gap down a a set of 67mm rings. 67 to 65 is not to much to ask, if that is your only option?

I have been doing it my entire life.

What brand of piston is it?
Measure the ring grooves please,
the best way to do that is with a clean set of feeler gauges and confirm their sum with your digital vernier.

For a while in the very early days of Norm Frasers and back up parts for Montessa, the only rings he supplied to crisp up your Monties were all 2mm(0.080") over.
"light weight, and it works great"  :)

HeavenVMX

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Re: New Rings
« Reply #6 on: May 31, 2016, 09:17:09 pm »
Hi Rob, I wouldn't have any hesitation to gap down a a set of 67mm rings. 67 to 65 is not to much to ask, if that is your only option?

I have been doing it my entire life.

What brand of piston is it?
Measure the ring grooves please,
the best way to do that is with a clean set of feeler gauges and confirm their sum with your digital vernier.

For a while in the very early days of Norm Frasers and back up parts for Montessa, the only rings he supplied to crisp up your Monties were all 2mm(0.080") over.

Norm Fraser & Montesa ??? Do you mean Bultaco?

Offline monte34

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Re: New Rings
« Reply #7 on: June 04, 2016, 06:30:17 pm »
Thanks for all your comments, I decided to order the 66mm ring set to suit the original piston. When it turns up I will have to find out how to file it down to size (might be a bit beyond my skill level)
Cheers   Rob

Offline pokey

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Re: New Rings
« Reply #8 on: June 04, 2016, 06:44:10 pm »
I use a points file and take my time. measure mark with a nikko pen and get close then measure and final few strokes.

Offline yamaico

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Re: New Rings
« Reply #9 on: June 04, 2016, 07:10:00 pm »
I use a 6" flat smooth file. I take the handle off the file then clamp it in a vice, facing out horizontal, narrow side up. Grab the ring either side of the gap with both hands, compress it against either side of the file and go backwards and forwards, continually checking the ring gap in the bore (0.003"/inch bore usually). Once the gap is correct then trim the pin notches the same way. Simple as and very quick to do.

Sorry if the description is a bit hard to understand - I can see it in my head, but it probably doesn't translate too well. :-\

Offline geoff

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Re: New Rings
« Reply #10 on: June 04, 2016, 09:15:35 pm »

Easy to follow and the best way to arrive at the same amount removed from each side of the ring. Also less chance of breakage that way.

Offline monte34

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Re: New Rings
« Reply #11 on: June 04, 2016, 11:27:37 pm »
I understand what you're saying, will have a crack when the rings arrive.
Thanks,   Rob