+1 size piston rings

Hi

anyone know where i can get these for a 1981 XJ50RH

Cheers

Craig

 

I've heard the first oversize is unavailable. Did you buy pistons?

Check with Chacal - - INFO@ XJFOREVER . com

 

4U8-11610-10-00 PISTON RINGSET 1ST ALTERNATE PART

Try this Part Number.
The good news is ... there's a Part Number!!!

 

thanks guys...no new pistons...i am hoping to just get the upsized rings....

 

4U81161020
(4GA-11605-00) PISTON RING SET (0.50
Note: this part is superseded by 4GA1160500. € 27.50

Try http://www.cmsnl.com/yamaha-xj550rh-198 ... /A-07.html

The 1st oversize is not available but 0.5mm oversize is. They are 27.5 euros per set.

They are in Holland.

 

You should just fit new standard rings, if you are not reboring & fitting new pistons...

 

Bores 1 2 3 4
Top 57.06 57.05 57.05 57.05
Middle 57.05 57.05 57.05 57.05
Bottom 57.03 57.03 57.025 57.03
Taper 0.03 0.02 0.025 0.02

here are my bores measurements after honing

 

sorry, i should have said, any suggestions for me here with these bore sizes? I could get them bored out to 57.05 and then use the +.05 rings? or?

Bores 1 2 3 4
Top 57.06 57.05 57.05 57.05
Middle 57.05 57.05 57.05 57.05
Bottom 57.03 57.03 57.025 57.03
Taper 0.03 0.02 0.025 0.02

 

I think the rings I found in Holland (may be available down your way?) are +0.5 not 0.05. I would have thought you would need pistons as well.

I will have to defer to an XJ expert on this!

 

just so i am getting this rightish..

I have assumed!!, that I can use +1 size rings in standard size pistons where the bores have worn slightly…and it doesn’t mean buying +1 size pistons as well…??

If that is not the case then I will buy new larger pistons and rings and get the bores bored out to suit…

 

Yes, you have to acquire the correct oversize pistons to go with oversize rings! (or vice-versa might be more descriptively correct). And the cylinder bore needs to be sized correctly for the size piston you are using!!

 

For the 550 or the 650? You omitted a digit...

 

Sorry for the double post, but...

Must be for the 550? If so, why not use new standard rings?

According to the factory book, bore limit is 57.10, and max taper is .05mm.

Looks to me like you're still well within stock specs; why not just a hone and new rings?

 

Take an Over-sized Compression Ring an fit it "Squarely" in the Cylinder and measure the Gap in the Ring within the Ring's Up-Down Travel.

Cross-ref the Measurement to Ring Gap Specs and determine how you stand with the One-over's in it.

If the Gap's too wide, ... you'll know by how much and what to do.
If the Gap is too close ... don't File the Rings.
Hone the Cylinder.

 

Honing the bore just takes the glaze off, it shouldn't make the bore any bigger.

 

thanks all, as always im impressed by the knowledge and help!!...i would prefer to stick with the original pistons, and just thought i could go +1 because of the wear, i am reading here i can use the standard rings, right??

 

Correct. According to factory specs, you're still well within the wear limit for the stock pistons and rings. As long as the cylinders need nothing more than honing, stock rings should work fine.

I'll scan you the cylinder/piston/ring specs page from the factory book if you want; PM me your email address.