Steve Best
Well-Known Member
The chrome cylinder will not wear measurably at all (at least by caliper).
Once it wears at all it tears the chrome and hits bare aluminum, game over, no replay.
The rings wear considerably however, and if they get hot they get soft.
I still use a dial caliper for most measurements around the shop down to half a thou.
Eyes are getting bad so I find it hard to read a verier these days. Love the dial.
Hate electronic. Dead batteries, offset zero, etc, etc.
I like the Mitu has inch and metric on the bar, although the dial is inch only.
You are a head-popper too? Four nuts, why not? Tells a lot looking in there.
You must be running synthetic if the carbon wiped off.
I like to run the last kilometer at full throttle so I can read the plug and piston wash.
Wet fuel washes the carbon off the top edges of the piston at the ports at WOT.
This piston above is pretty darned good, I'd like to see less wash.
No wash means too lean or you were not running it hard enough for long enough.
If you have no scream at WOT top end you have to look at your main jet.
Probably not lean or you would have toasted the engine long ago.
It is all down to looking at your plugs.
I look at the well worn plug after a long WOT blast.
Black? need to go leaner on the jets.
Tan coloured? You are close. Time to get a new plug and do a plug chop to be sure.
My opinions...
Steve
Once it wears at all it tears the chrome and hits bare aluminum, game over, no replay.
The rings wear considerably however, and if they get hot they get soft.
I still use a dial caliper for most measurements around the shop down to half a thou.

Eyes are getting bad so I find it hard to read a verier these days. Love the dial.
Hate electronic. Dead batteries, offset zero, etc, etc.
I like the Mitu has inch and metric on the bar, although the dial is inch only.
You are a head-popper too? Four nuts, why not? Tells a lot looking in there.
You must be running synthetic if the carbon wiped off.
I like to run the last kilometer at full throttle so I can read the plug and piston wash.

Wet fuel washes the carbon off the top edges of the piston at the ports at WOT.
This piston above is pretty darned good, I'd like to see less wash.
No wash means too lean or you were not running it hard enough for long enough.

If you have no scream at WOT top end you have to look at your main jet.
Probably not lean or you would have toasted the engine long ago.
It is all down to looking at your plugs.
I look at the well worn plug after a long WOT blast.
Black? need to go leaner on the jets.
Tan coloured? You are close. Time to get a new plug and do a plug chop to be sure.

My opinions...
Steve
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