XS Rings

I don't think so. They changed the top ring on the TX650A, after engine #010152. The change was from a 1.5 mm thick ring to a 1.2 mm ring.
 
Just to clarify will the acura rings work on my 81? I am rebuilding my 650 right now and I work at an acura dealer, so that would be pretty convient...
 
So I was looking at this ancient post and at the hastings catalog. I'm actually looking for a set for the first overbore, so 75.5. I thought about it and searched for 75.50mm and came up with standard set:
2C4884 Mitsubishi, 1997-02 1.5 Litre 1468cc Eng., 4G15,
75.50mm, 4 - 1.2mm, 4 - 1.5mm, 4 - 2.8mm

The dimensions are right, any reason these wouldn't work? They seem to be a little easier for me to find than overbore Honda's.

Edit: Went back to glance at this and realized I had some info incorrect. These would work for 2nd overbore, not first.
 
Last edited:
You know, I kept seeing this posted over a few forums. My head gasket was weeping so I decided to re-gasket the top and sides while I was at it. I decided to clean the pistons and head too. I ended up breaking one of the rings. So, since I could not get a set readily, I ended up searching for the various posts I saw concerning using car rings for your bike. I got the Acura rings. Same number. First problem, the inner oil ring did not fit. No problem. Used the old inner ring. Next problem, I put the bike back together. Started right up. Accelerated and lo and behold, my bike put out better fog than a fog machine. Outside of a valve stuck wide open, which you would not only hear but feel, the only other conclusion would be the rings. I didn't mention earlier there was not even a trace of smoke prior to me changing those rings. I know how to set rings so that wasn't it. I probably should have measured them but saw so many posts concerning the use of these that I figured what the heck. And I NEVER take things for granted when working on vehicles, but I did this time and it bit me in the proverbial.

Minus the $55 for the poor advice from the guy who has gone to so many forums to post this info, my bike will live to ride smoke free again as I have ordered a set of original rings (original bore on this bike with super clean walls) online.

My advice to you. Be careful when you stray from what is made for your machine. Aftermarket parts that are designed for an engine are fine, but ones that are not specifically designed for a bike might not work. Stick with what was made to work and your bike will live a long bike. I have owned a lot of bikes, and to me, the XS650 is the King of the Road! Take care of your baby with original/OEM/aftermarket parts specifically made your machine.
 
Just a little update on this thread to clarify ring dimensions and profiles for the 447 pistons, and for the different 256 pistons.

Extracted from '74-'83 447 service manuals:
447-Rings.jpg TX650A-PistonRings.jpg


Extracted from '70-'73 256 service manuals (ring thicknesses annotated in red):
256-Piston&Rings01.jpg 256-Piston&Rings02.jpg 256-Piston&Rings03.jpg 256-Piston&Rings04.jpg
 
Last edited:
fhoffman said:
my 1974 xs650 has different thickness piston rings. where can I find the right size? or should I change pistons (code is 447)
Click to expand...

If you have 447 pistons, they should be 1.2, 1.5, 2.8 mm thicknesses.
Measure your old ones to be sure. 1974 was the transition year.
447 rings are easy to find. Yamaha, MikesXS, eBay, eBay:Cruzinimage vendor.
 
Size matters but also what they are made of also matters. I think Yamaha used a chrome top compression ring and a non chrome 2nd ring. Something to think about when buying rings.
 
I just pulled down my engine after 6-10,000 miles (however long a Brigestone rear tire lasts on one of these, my odometer is busted). Rings looked to be in very nice shape, i couldn't measure any wear on the rings that was outside the size range of the remaining two sets of new rings. Didn't appear to be much for blow-buy discoloring on the pistons, either. all-in-all, I'd say they're doing their job as well as anyone could ask.
 
am a retired motorcycle tech with 48 years experience and have rebuilt hundreds of motors including the XS650 ..when it comes to rebuilding motors I know lots of tricks I learnt from Honda technicians when I worked for Honda and also when I started a motorcycle service center ...the first XS650 I worked on ..taking the motor out and lifting it nearly broke my back cause they are so heavy for a 2 cylinder motor..so if anyone wants info just ask
 
I'd be interested to know what tricks or knowledge you have gained in overhauling the XS650 engine. Update 6 months later billy mitchell has get to reply.
 
Last edited:
Back
Top