cylinder dimensions 305

mapotoast · Post by **mapotoast** » Tue Mar 09, 2010 3:55 pm

Hi, Glad you guys are here, thanks. I'm starting my first 305 rebuild. I just took some measurements on my cylinder ID and believe they are out of range with the limit I found in Silver's engine manual. I have 2.368 and 2.367, Should I be in the market for .25 size 2 rings and pistons?

Also in my parts manual some piston listings have an (x) or (s) in front of the parts number. What does this designate.

FAST FRED · Post by **FAST FRED** » Tue Mar 09, 2010 5:03 pm

IN A STANDARD ISSUE HONDA PARTS MANUAL OR HONDA PARTS FICHE (AS SEEN ON LINE FROM MANY SOURCES) I SEE NO (S) OR (X) LISTED IN FRONT OF THE PART NUMBERS. I WOULD SUSPECT IN YOUR MANUAL IT MIGHT MEAN STANDARD (S) AND OPTIONAL OR OVERSIZE (X). IN A STANDARD MANUAL THIS IS LISTED AFTER THE PART NUMBER AND DISCRIPTION IN THE COLUM THAT SHOWS THE NUMBER OF THAT PART NUMBER USED IN THAT PARTICULAR PAGE. IF THIS NUMBER IS IN PARENTHISES, IT MEANS THE PART IS NONE STANDARD OR OPTIONAL. LOOK IN YOUR MANUAL AND CHECK AND SEE IF THE OVER SIZE PISTON PINS (13112-251-305) HAS A (X) IN FRONT OF THE PART NUMBER, IF SO THEN THAT WOULD LEAD ME TO BELIEVE THE (X) WOULD INDICATE NON-STANDARD.
FAST FRED

teazer · Post by **teazer** » Wed Mar 10, 2010 12:03 am

2.368" is about 60.14mm which is quite a bit larger than the stock 60mm.

If your barrels are round and not scored or pitted, it may be possible to bore and hone them to take 0.25mm pistons. If the surfaces are bad and/or teh bore is worn out of round you may have to go to 0.50mm o/s.

mapotoast · Post by **mapotoast** » Wed Mar 10, 2010 2:16 pm

Thanks Fred, I'll have to look that part up on my list.

mapotoast · Post by **mapotoast** » Wed Mar 10, 2010 2:19 pm

Teazer, thanks for the info. Cylinder liners look good. They were already honed out before my measurements. Guess I'm in the market for .25mm pistons and rings.

Marc