1981 kz1000LTD O/S rings

I am looking for some kind hearted soul who may have 4 new sets of 0.50 oversize rings for my old kawasaki kz1000ltd (k model). or advice where to obtain same. part# 13025-5018. Have tried kawasaki and usual suppliers to no avail. Kawasaki Canada and USA skow them on back order which I've been informed may indicate they have been discontinued.

O.50 oversized is a bunch over.Did u mean .050? Even then that is a LOT.Ru sure u need to go that much over?Ru building a hot street motor or something?Just sounds like a lot.bj

hocbj23 wrote:

O.50 oversized is a bunch over.Did u mean .050? Even then that is a LOT.Ru sure u need to go that much over?Ru building a hot street motor or something?Just sounds like a lot.bj

He means 0.50mm which is how kawi specs them. "First over" is 0.5mm and "second over" is 1.0mm in the Kawi factory parts. Some of the aftermarket places go in steps of 0.25mm.

.50 mm is the same as .020" over sized just in case any body is curious.

OK .I guess I was thinkin in the old hot rod vernacular of 20 over =.020" not mm.bj

Thankyou Bountyhunter for setting the "kids" straight on Kawasaki piston oversize measurements. My error to assume users of this forum would know what I was talking about. I bought this grand old lady a dozen years ago after I got my kids educated and out fishing for themselves. She had been compiled from 3 bikes and was in pretty decent shape for an east coast bike (rust issues etc.) My guess was that she had been ridden hard and put to bed wet a few times so I undertook some restoration work. New tires, battery, chain, sprockets,paint job, dyed the seat cover,valve and seat grind, cylinder bore(1st over)with new Kawi pistons and rings,new engine mount rubbers along with a myriad of other little things were done.(Many thanks to a factory trained mechanic of the 70's-80's (Little River Racing) Many hours of polishing with 3 grades of buffing compound made her shine. The old gal has only seen warm sunny days since and has spent many hours on the back roads of New Brunswick running with a ZR1 and a ZX10 and always put away in the garage.
I started to notice a little oil consumption and recently did a compression test and found # 1 cylinder down to 125psi and am in the process of re-ringing and checking out the valve train. I will go back through my pictures of nine years ago and will post one of my "CLASSIC". More to follow as it happens. May have to stick her back together until I can find my ring sets so I can enjoy the summer months. Later... Happy and Safe Riding to all Kawi riders

I have found that when my compression is going south, it is because of bad valve seals. They seep oil after I turn it off which runs down and bakes onto the valve seats. Over time, that builds up until the valve is not sealing well. Both times I had to do engine work, that was why. I didn't have to rebore until my engine had 75k miles. It still had factory pots and rings.


The only place I have seen pistons or rings for the 900 or 1000 engines is on Fleabay. They are so expensive, some people just buy the 1075 aftermarket kits instead.

You might try a light hone and reinstall the rings. I would be surprised if they were bad unless there was damage from rust or some other bizarre problem.

Bountyhunter, thanks for the tip regarding the valve oil seals. It just so happens that I purchased a valve spring compressor yesterday and my buddy and I are going to put her back together this weekend time permitting with a new set of seals and gaskets.

The cylinder walls look real good with lots of cross hatching still visible from the over bore and honing 10 yrs. ago. Really not that many miles on the rebuild. No ring ridge present. Compression test indicated low on #1 and thought I'd re-ring while I had it apart. Hopefully this is not the case. You're right, big buucks for replacement rings now.

Nice to have someone with your knowledge and insight about these old girls available as a sounding board. Thanks again. I'll post when she's road worthy and let you know how we made out.