142f black oil

[45u]

Sorry seats in. Do you know why you have a crosshatch on most cylinders????? One to hold oil and to help the rings seat. If I had time to show pictures of all the pistons I took out of motors I built would take me two days or more. I am always building a Harley motor for someone or motorcycle motor and have not been with out at least one I was building for 40 plus years. Been know to have 15 or more going at one time. A few of my machines and some gauges. When it comes to Harley s I can balance the crank, rebuild the rods and MUCH more and been doing it for 40 plus years as well as many other brands of motorcycles. Most of my living has been make working on motorcycles of all brands. Do you know the best piece of metal to machine do not care what they did at the factory??????????????? One that has been sitting out and the weather for years as only gets better with age and MUCH harder. Do the research and you will see if you do not trust my word.
Thanks
Jeff

 

[45u]

This is how I work on my rig when I do not take the sidecar off. She is my only transportation as I hate a cage!!!!!!!!!!!!!! Other then when I had children been that way for most of 45 plus years. Buy the way do some research on heat cycling you might be surprised.

 

[HeadSmess]

done plenty of research on "heat cycling", it means zilch, so i am surprised!

that people fall for it...

yep, im all too aware of why they crosshatch cylinders. done properly. with correct break in, and the correct ring/cylinder wall material combination, they usually stay visible for... the life of the engine. cast iron is the exception, that stuff leaves nasty ridges at the tops of a cylinder, they even make a tool for removing said lip.


they (used to, when companies like cincinnati made machine tools properly) leave (rough machined) castings out in a paddock for years before taking the finishing cuts.

nothing to do with hardness, everything to do with released tensions in the casting (once the hard, outer, sand filled skin has been removed) having time to normalize. its common practise in precision machine work to leave castings alone to "do their thing"

doesnt happen too much these days, everyone wants it NOW!

picture time huh?
Photo0251[1].jpg
just having a go at cutting a gear with this new-fangled software i got... generated involutes with a slit saw, not using a formed cutter.


oh wow its hard to post pictures now... or is it? why did the upload file option just appear? after posting? hmmph.

 

[45u]

Evidently you did not do very good research and do not have a clue about atoms. But whatever you are correct and everyone else is wrong??????????????BS

 

[HeadSmess]

so, your harley uses lapped aluminium piston in a chrome-plated brass cylinder, and is two stroke, and runs on methanol? the only engines that require "heat cycling" are small nitro engines. and theres a reason they dont make lapped piston/cylinders with much more than 20mm bores...

strange, i google heat cycle, the first hit that pops up says what i say, heat cycling is nonsensical in ringed engines.

then there was a lot of hits for heat cycling tyres...

then the occasional hit to harley forum boards where people that dont know much postulate the theory that an engine needs heat cycling to "heat treat" its internals... ignoring all the facts about metallurgy in the process, of course.

but then, harleys are just glorified industrial engines stuck on two wheels.

but what would i know? i couldnt tell a flourine atom from an argon atom... apparently

must be all the actinides and lanthanides ive collected, making me fuzzy in the brain.

cmon, mr chemist, tell me about the atom

or tell me about what percentage carbon turns iron into steel... and then how much more carbon is required to go from mild steel to tool steel.

mehanite? austinite? pearlite? all the same stuff... oh, and so is cementite... so what are they?

 

[45u]

so, your harley uses lapped aluminium piston in a chrome-plated brass cylinder, and is two stroke, and runs on methanol? the only engines that require "heat cycling" are small nitro engines. and theres a reason they dont make lapped piston/cylinders with much more than 20mm bores...

strange, i google heat cycle, the first hit that pops up says what i say, heat cycling is nonsensical in ringed engines.

then there was a lot of hits for heat cycling tyres...

then the occasional hit to harley forum boards where people that dont know much postulate the theory that an engine needs heat cycling to "heat treat" its internals... ignoring all the facts about metallurgy in the process, of course.

but then, harleys are just glorified industrial engines stuck on two wheels.

but what would i know? i couldnt tell a flourine atom from an argon atom... apparently

must be all the actinides and lanthanides ive collected, making me fuzzy in the brain.

cmon, mr chemist, tell me about the atom

or tell me about what percentage carbon turns iron into steel... and then how much more carbon is required to go from mild steel to tool steel.

mehanite? austinite? pearlite? all the same stuff... oh, and so is cementite... so what are they?

Whatever! I am over it and I only thought my spelling was bad! I do not lap any cylinders or pistons! Harley s are not nickle seal. I bore and finish my cylinders to .0002 so they need nothing but breaking in when I am done. You are one up on my as in 45 plus years of machining I have never heard of lapping pistons and cylinders is this something you came up with would not surprise me!!!!!!!!!!!! You can lead a horse to water but you cannot make them drink.
Have a nice day I am.
Jeff

PS My Harley has over 116,000 on her all but 5 states and has 5 provinces. It is my only transportation just the way it has been

 

[Old Bob]

Nitro engine cylinder liners are lapped. Been done that way for 80 years or so.

heat cycling after machining does nothing, any heat treating, including cold stabilization, should be done BEFORE final sizing to be effective.

Break in is determined by a few thing such as plain bore vs chrome bore, roller/ball bearings vs babbit.
On M4 Hondas I recommend a gentle break in for the first hour, its a plain bore diamond turned, you need to work the whiskers off gently, on a chrome bore 2 smoke with roller bearings no break is needed and it should not idle and should get full throttle blasts to seat the ring.
My 4 stroke Honda engines run over 16,000 rpm so I'm sure I know nothing.

 

[HeadSmess]

they have been lapping for hella long time now... things like diesel injector pumps, high speed bearings/bushes, flat surface plates...the list goes on.

im not sure nitro engines have even actually been around for 80 years...close to it but small IC engines have been around since the (very late) 1800's.

hmms, i read about this only a few weeks ago...

*searches*


ahuh!

http://www.modelaviation.com/enginehistory


halfway down, first commercial glowplugs circa 1947... or 69 years ago.



the smell of burning ether, kerosene and oil is so much nicer than the eye stinging reek from nitro engines shame its so hard to get hold of!

and these days, electric is overtaking everything

 

[skyash]

True that even 5 percent in my 66cc made my eyes burn when you stop at lights

 

[sbest]

"Heat Cycling" has some value to get gaskets and sealers to set, with bolt retorque between cycles, but I am a "run'em hard" fan. Like Headsmess, I've torn down shortly after break-in (for various reasons) and looked for the carbon his pictures show. Light use on break-in does not seal well on roller bearing chrome or nikisil engines. I think Old Bob's comments are right for old school cast and babbit engines and KC Vale's break in is pretty much how I do it, 2 stroke and 4, in practical terms.

Awesome gearcutting Headsmess. When cutters were not available I've used a custom ground flycutter. You know how much fun that is.

Finally, to help with logic here, I'd like to offer this PDF link:
https://yourlogicalfallacyis.com/pdf/LogicalFallaciesInfographic_A3.pdf