Topic: Piston ring advice CB750 ('72)

[thomellis]

I've been looking around for a new set of piston rings, and just wondering if anyone had any advice on any to avoid or recommend.   I searched and found a few threads, but nothing too recent so thought I'd poll the forum. 

There seem to be a few sets on ebay, does anyone have any experience with any of these:

http://www.ebay.com/itm/HONDA-CB750-PISTON-RINGS-SET-FOUR-STD-SIZE-1969-76-/290666243453?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item43ad0ee57d#ht_2027wt_1163

http://www.ebay.com/itm/180808943805?item=180808943805&viewitem=&sspagename=ADME:X:RTQ:MOTORS:1123&vxp=mtr#ht_691wt_648

http://www.ebay.com/itm/Honda-CB750-Piston-Ring-Set-CB750-K-/380406813826?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item5892035482#ht_3228wt_902

Thanks in advance for any input/insight you guys can offer.

[VTCBike750]

Interested as well

[Ceebeehead]

In my trolling the forum for various things, I've heard positive things about the NPR rings.  Not up to the snuff that are the stockers, but in the top three I would say.  As a general rule I go for the sets with 3-piece oil rings, haven't heard anything about the 1-piece like that second set.  Good luck on your build.

[HondaMan]

Most of the 750K2 pistons came with 1-piece oil rings. The last couple of months of production did not.

If yours are the 1-piece type, look up the "MC" brand of rings on eBay, sold by Mrssuperdeals. They work well and are my favorite aftermarket rings. In general, I prefer these rings anyway, but if you want the 3-piece oil rings, you'll have to look elsewhere.

Just my pennies' worth!

[thomellis]

Thanks for the replies guys.  I found the seller HM mentioned, but looks like he currently only has oversized rings:

0.75mm
http://www.ebay.com/itm/FOUR-New-Honda-Piston-Ring-Sets-CB750-CB-750-75-Rings-/110778132120?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item19cae42698#ht_740wt_1163

1mm
http://www.ebay.com/itm/FOUR-New-Honda-Piston-Ring-Sets-CB750-CB-750-1-0-Rings-/360303695161?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item53e3c61539#ht_1183wt_1163

[thomellis]

Thought I should send one more update here.  I sent a message off to mrssuperdeals (mrsuperdeals wife of course ;P) and got a response back saying they do in fact have the standard rings available, going for $70.  A little bit pricier than the other sets I've found, but I don't think HondaMan would lead me astray, so probably worth the extra couple bucks.

[HondaMan]

Just be sure to hone the old ring marks out of the bores when you install those new ones. If by chance you have my book, take a look at the pictures showing the honing sequence and you'll see what I'm trying to say (in the pictures). You're going to want to go beyond "breaking the glaze" on the walls, to a full hone. Then those 1-piece rings will set right in.

[thomellis]

As one final addendum, you can get the rings here:

http://www.rustyriders.net/engine/4-ring-sets-honda-cb750-std.html

Which is the actual website for the seller mrssuperdeals.

cheers!