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jonolanracin
12-08-2015, 09:59 PM
I have a cylinder and the piston is a 68.25 and i thought 68.00 was all you could go so is this a big bore cylinder it loks like there is plenty of room to be bored out more

Queef Chief
12-09-2015, 08:49 AM
I was thinking 69.5 was max on stock bore, but i could be mistaken.

John Tice
12-09-2015, 09:51 AM
Check Wiesco.com



John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

Queef Chief
12-09-2015, 10:58 AM
My '86 is currently at 69mm, and the Wiseco catalog I ordered from went to 69.5mm.

jonolanracin
12-09-2015, 09:12 PM
Ok thanks for the info ive had no luck finding a 68 75 piston yet

John Tice
12-10-2015, 10:12 AM
You won’t ordinarily find Wiesco pistons with .25 or.75mm increments. Wiesco traditionally only supplies pistons in .5mm increments. .25mm steps doubles their inventory & probably wouldn’t increase their sales.

John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

John Tice
12-10-2015, 10:35 AM
You won’t ordinarily find Wiesco pistons with .25 or.75mm increments. Wiesco traditionally only supplies pistons in .5mm increments. .25mm steps doubles their inventory & probably wouldn’t increase their sales.

Many times a worn cylinder, especially a 2 stroke won’t clean up with a .25mm oversized piston.

John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

jonolanracin
12-10-2015, 08:12 PM
Thats why i wanted the .75 im at 25 now and i dont want to buy a 50 and not be able to use it
You won’t ordinarily find Wiesco pistons with .25 or.75mm increments. Wiesco traditionally only supplies pistons in .5mm increments. .25mm steps doubles their inventory & probably wouldn’t increase their sales.

Many times a worn cylinder, especially a 2 stroke won’t clean up with a .25mm oversized piston.

John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

John Tice
12-14-2015, 09:26 AM
If you take your cylinder to a reliable shop & have it properly measured, maybe a .25mm step is all you need to clean up the bore. Send the cylinder to me if you can’t find anyone closer.
I’ve got no idea of how you are measuring the bore but you might be better of to let the cylinder boring man do your measuring.


John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

freewheeler
12-14-2015, 10:38 AM
You won’t ordinarily find Wiesco pistons with .25 or.75mm increments. Wiesco traditionally only supplies pistons in .5mm increments. .25mm steps doubles their inventory & probably wouldn’t increase their sales.

Many times a worn cylinder, especially a 2 stroke won’t clean up with a .25mm oversized piston.


Interesting info, from an engine builder.

http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xwiseco+.7 5.TRS0&_nkw=wiseco+.75&_sacat=0

http://www.ebay.com/sch/i.html?_odkw=wiseco+.75&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xwiseco+.2 5.TRS0&_nkw=wiseco+.25&_sacat=0

John Tice
12-15-2015, 12:42 AM
Great finds for oddball Wiesco piston sizes; any of us who does business with Wiesco on a regular basis knows that these .25mm & .75mm piston sets are unusual situations. Just because these particular pistons are found in the 1/4mm dimensions don’t expect to find them for your machine. The early model pistons which are packaged in a Blue box; these are cast pistons with brittle moly filled iron ring sets. Please avoid this type of piston for high performance applications.
For any of you who doubt this; ask for Ron or Al in the power sports section. 800-321-1364 :wondering

John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

onformula1
12-15-2015, 01:00 AM
You won’t ordinarily find Wiesco pistons with .25 or.75mm increments. Wiesco traditionally only supplies pistons in .5mm increments. .25mm steps doubles their inventory & probably wouldn’t increase their sales.

Many times a worn cylinder, especially a 2 stroke won’t clean up with a .25mm oversized piston.

John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

I think the key word is in this sentence- You won’t ordinarily find Wiesco pistons with .25 or.75mm increments

Jmoozy27
12-15-2015, 01:58 AM
Interesting info, from an engine builder.

http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xwiseco+.7 5.TRS0&_nkw=wiseco+.75&_sacat=0

http://www.ebay.com/sch/i.html?_odkw=wiseco+.75&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xwiseco+.2 5.TRS0&_nkw=wiseco+.25&_sacat=0

Do you come on here just to criticize people?

onformula1
12-15-2015, 02:25 AM
Do you come on here just to criticize people?

Unfortunately, John doesn't get the same play here as he does at E2S, where he is like a cylinder god and gets huge props.

(Some) Guys he has been building cylinders for what? 44 years!, he knows what he is talking about, embrace him and learn, I have been building engines for 30 years, I have learned a lot from him, you can too, he is willing to teach us all the tricks and asks for nothing in return, he has even offered free work to help people out. This man should have a "Star" next to his screen name.

(And no I have never shook his hand, just a fan)

Nitric Acid 69.5% Cleanroom LP, Thank You John!

ironchop
12-15-2015, 12:38 PM
Unless you are beating your own drum around here nearly every minute, some folks mistake humility for ignorance. They also mistake arrogance for wisdom.

I guess I need to get a membership over at E2S. I didn't even know about the place until recently.


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John Tice
12-15-2015, 08:54 PM
Time to get back to education; we can all learn from each other. I also found a .25mm over Wiesco piston last month, on occasion they will show up. As said before; this isn’t a standard production run part. Lets turn "Lemons into Lemonade"

As we are all aware; the EPA & the tree huggers have all but killed our beloved 2 stroke machines. www.everything2stroke.com is also becoming difficult to keep the fire stoked up. “How it’s Done” will be a regular thread in 3wheelarworld from now on. Any of you with cylinder questions are encouraged to chime in. In our shop, Small Engine & NW Sleeve the repair work is 10-1 in favor of 2 strokes. The plated cylinders are really starting to come in the door. The sleeve job is still the king as long as the piston manufacturers continue to make oversized pistons.

Thank you for the kind comments

John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

oscarmayer
12-17-2015, 02:17 PM
have you thought about a vortex piston?

onformula1
12-17-2015, 04:00 PM
have you thought about a vortex piston?
Shhhhhh! LOL

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jonolanracin
12-19-2015, 12:06 AM
Never heard of them

John Tice
12-19-2015, 11:46 AM
I looked over the Vertex catalog; very impressive product lines. It seems as though Vertex has taken the cylinder manufacturing the same direction as most others, plated cylinders. Plated cylinders are cheaper to manufacture; plated cylinders eventually wear out as they all do over time. Vertex doesn’t manufacture oversizes to run in borable iron cylinders.

John Tice
503-593-2908 Alternate 541-508-3944
www.smallenginemachineworks.com & www.nwsleeve.com
Turning Custom Cylinder Sleeves Since 1971

cbx1170
12-21-2015, 10:34 AM
Pistons in +.25mm & +.75mm sizes in each millimeter over are easy to make its tough to get a ring manufacturer to make rings that size in quantities wanted. Thats the problem. Buy extra rings at the same time you buy a specialty piston kit. Hint.

oscarmayer
12-27-2015, 10:35 AM
^always buy 2 spare rings and if smart, 2 piston kits and 4-6 spare rings.


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