Top End Time?

Anyone know the average life expectancy of a set of piston rings, or the typical mile interval between ring changes?
Twenty-thousand miles since a 2015 top-end, and I'm adding oil every couple hundred miles to maintain the level.

:blink:

I have around 50000 miles on mine and I reused them. I'm using about the same. Pics of the plugs?
Steve

Removed the plugs and took these pics in response to Steve's post. The carbon may be partly from running half a tank of mid-grade fuel, but likely some oil there too.
Played around with various air jets after that, and have .7 in now instead of .8. Had short 30mm stacks for the last couple hundred miles, and now have the 70mm set back on.




:huh:

Not too bad. When my valve guide seals were shot I had to go down on the pilots to burn the oil. You've got lots of time left.
Steve

Daveo what grade fuel do you normally run?
I think 87 would burn hotter

87 Regular fuel does work best. I have always had resistor spark plugs OR resistor caps in my ignition setup, and solid core Dynatek wires. I don't know, maybe it's time to try a set of non-res, or hotter spark plugs.
It is definitely time for an engine oil change though. Been burning Shell 4T Rotella the last year or so.

What compression pistons are you using? At 10.5:1 I believe US 93 octane is minimum. All the calculation tables I've seen suggest even higher than that for optimal burn. Plus, 93 typically has less methanol to plug your carbs than 87. And I can't see changing fuel affecting oil consumption?

A huge oil consumption is a piston ring blow-by or weak sealing effect.

VTEC wrote: What compression pistons are you using? At 10.5:1 I believe US 93 octane is minimum. All the calculation tables I've seen suggest even higher than that for optimal burn. Plus, 93 typically has less methanol to plug your carbs than 87. And I can't see changing fuel affecting oil consumption?

My engine has stock Kawasaki Std size pistons that were installed in 2015. The head is from a 84 ZN1100, and cams from an 84 ZX1100.
Having those pistons with the valve pockets enlarged for valve clearance makes me think that it has less-than original factory engine compression. According to the Kawasaki service manual, a 1982 KZ1100 boasted 8.9 and the 1984 ZN1100 was 9.5. Since my engine is a hybrid (or lobrid) I don't know what the compression ratio actually is.
It runs cool, revs up quick, and loves the upper rpm range. I'm addicted to zinging around at 6-7k as much and often as possible, which may explain where the oil is going.

Scirocco wrote: A huge oil consumption is a piston ring blow-by or weak sealing effect.

What do you think...does the spark plug condition indicate one or the other, or heaven forbid both?



:S

You have a oil carbon build up or a little fat air/fuel condition on yoúr spark plug colour.
How much oil your engine need on 1000 Km or 600 miles???

Looks fat to me. What main jets are you using. Remember, get the mains right then go to the air jets, the needles then the pilots. If you're giving it too much gas, the rings can "wash out" and you'll start burning oil. Not long ago you had that coveted tan color.
Steve