does anyone have the part # for the overbore piston and rings and what sizes they are,for the 78.5 mm Engine.

Here is the wiseco chart


Service Honda should have the Honda part numbers

http://www.servicehonda.com/hard%20part ... s_old.html

If you've never been to Service Honda's page, this may help:

http://www.servicehonda.com/hard%20part ... 20page.htm

Click on the piston/crankshaft link on the left side of the page.

the thing i cant figure out is the part # for the bore size example theirs two parts # for .25 over rings one set for the 78.5 Engine and one set for the 80.00 Engine.there a set of rings on ebay part #13012VMO681 what rings are these over bore for the 78.5 Engine or the 80.00 Engine.thanks jim

As far as I know honda NEVER made rings for the 80mm and up jugs, that's where Wiseco took over and probably why Wiseco never made any for below 80mm.

0.25 part#13011vmo305,0.25 part#13012vmo681.two diff part numbers. ?

You lost me I only see one part number for each size ring.

13011-VM0-305 RING SET, PISTON (STD)
13012-VM0-305 RING SET, PISTON (0.25)
13013-VM0-305 RING SET, PISTON (0.50)

Pistons

06131-VM0-305 PISTON COMP.
13102-VM0-315 PISTON (0.25)
13103-VM0-315 PISTON (0.50)

The Service Honda Fiche page shows BOTH part numbers, with the "-681" number being discontinued......

Happens all the time!

Usually means one part was superceeded.

part #13012VMO681 so this part # is the 0.25 overbore rings for the 78.5mm Engine

What bore size is the stock bore for the post recalled Engine?

The only pistons and rings you should be able to get from Honda if they still sell them and are not discontinued would be the pistons for the POST RECALL cylinder what ever size that is 60mm 400mm 26.98mm I have no clue what 78.5mm means, it is a meaningless number to me simply because I don't know what cylinder that bore size applies to pre recall post recall what ever, if you happen to have a PRE RECALL cylinder you will probably need to use the wiseco pistons.

my thinking 681 part# DISCONTINUED because that's the 80.00mm bore pistons.the 305 part# is for the 78.5 bore pistons.whata think ?

What does your current bore measure, does your current bore need bored over size?

i have the recall Engine 78.5 mm bore.i want to water cool the cylinder,relieve the cylinder and drill the holes in the piston.so im trying to find oem piston and rings overbores.trying to avoid boreing to 80.00 mm with the weisco pistons.

Pre-recall STD bore is 80 mm, post recall STD bore is 78.5 mm.

I would NOT put money on your assumption as the -305 number is the number that superceeded the -003 number. I have a 13012-VM0-003 set that appears to be 78.75 mm (ring end-gap measured by eye), but not a set of the -681 rings so I can't compare......

The pre-recall cylinder wasn't in production long enough (2-3 months) for Honda to have stocked 80 mm rings so I doubt that's what the -681 rings are for, but who knows....

There were also a lot of rings and pistons for the 350's with the -771 and -772 desginations and those aren't listed anywhere anymore....

Ok now I gotcha, that's a good idea to find some pistons and rings before sending it out for new sleeve hope your able to avoid the wisecos

im tryin just gotta figure out what part # are for what bore so i can get a set

The -305 and -772 designations are both for the post-recall (78.5 mm STD) cylinders.

I have both and their measurements are identical, I found another -772 piston also marked by hand as -305

hey Ody_Stable do you have any sets

the guy selling these rings part #13012VMO681 on ebay emailed me and said he cant figure out which rings these are for by the part#

Not that I can part with, we have two 350's on their STD bore, so I have been watching eBay and accumulating parts for future rebuilds when deals arise.

Have you asked the eBay seller of the -681 rings or piston if they will measure them for you?

The rings should have the over size markings stamped on them?

the 681 rings say their 0.25 over hoser but for what 78.5 or 80.00.nobody knows.im gonna ask the guy if he can measure them

I just did that, waiting on a response.

He wants too much for them in my opinion, I've never paid more than $25 for any 350 rings or $45 for a 350 piston. If you watch long enough you will find deals are there.

There's another guy asking for $54 for a 50 over set of -681 rings, highway robbery.........

hey Ody_Stable do you have any parts in your stock pile that have the 681 #