Enjoy your videos . I my self are old school engine builder . Built many race engines. Now into chain saws . learned a lot whatching you . like what you done to prep the piston . Also muffler mods. I think I heard your a vet I my self served in the Army Vetetnam 1967 1968. 199th light inf.Stay safe my friend.
Thank u so much Mr. Harvey, I really appreciate this more than u will ever know !!! I ❤ u buddy, I am so glad to meet a great human being as ur self, it's an honor to b able to say u r my friend !! And like u said we r just gonna try something with the cylinder and if just so happen it dont work out, then I'll just send u the hole saw and let u start over..🙏 I remember u sayin u like the "blue" 660 and this is one of the new 372 from china it came "blue".. i was told by the main man at farmtec thts now all of the holzffarma 372 r gonna come in he future is "blue".. so if u guys want one of the orange 372's u probably should go ahead an order one of the kit saws bfore thy switch to the all blue one's.. thts just a heads up to all of the great ppl tht is on mr Harvey's channel... good bless each and everyone of u...❤👍 again THANK U IRONHORSE !!
4.5???? When it changes direction!!! What a sexy piston!!! I’m so so happy I stumbled into this one....those little ticks and defects on a piston makes me crazy... I started all this curiosity about engine’s in high school when I bought myself a brand new Echo SRM 2501,,, and I had a little bit of general motor knowledge and I was reading my owner manual and it said that every season that you should de-carbon the cylinder if you want it to last a long time... Back when companies wasted time adding quality to their products.., anyway Echo had such a beautifully dished pistons and I was pretty green.., I’d seen a few dished pistons at the machine shop.., the piston in my Lawnboy... was just a regular one piston but boy howdy .,, my string trimmer was juiced!’n😂😂😂
I asked you a while ago , how to work a 372 piston. I am building my own shop ,and when im finished,i am gonne build an 372xp. Verry nice movie and good tips. Thanks Harvy Greatings from holland
Since I have started doing this whole reduction in my pistons and the rotational mass total weight and seeing what the overall power increases are possible with just this little modification I’ll be studying the piston and cylinder relationship and seeing where it can be reduced, for certain!!! It’s a fantastic idea for the weight reduction and the timing numbers modification and your only playing with your pistons specific’s!!!
I’m here from a motorized bike group watching this cause I’m working on building a high performance bike shooting for acceleration and top end I was reading in a group I’m in about shaving weight on a piston and some of the benefits this was an interesting and informative video thx man! Enjoying your videos Edit: my engine is a hybrid saw cylinder with the top chopped off for a cnc billet head to go on for cooling on a China doll transmission that will run a sthil-046 pop up connected to a long rod 40mm stroke
I used to port and polish clylender heads in a machine shop. I think what you are trying to say is that you are eliminating hot spots. When you have ridges it creates hot spots
I think my Dad told me it can also create weakness points when one has sharp and or rough finished edges, especially in fast moving parts such as pistons, valves, etc etc
Shoe files - they are called Swedish files. Every gunsmith has a set and I am a gunsmith. I have lost a few and broken a few through the years but I stile most part f them. One thing I have noticed about some pistons is the front and back measurements are not the same. One side appears to be taller than the other. I mic them out and sand them until they both are the same height, cylinder top to the bottom of the skirt.
I have the same scale! I just built a scooter top end, with big bore, I bought the scale, because I wanted to compare the Piston weights, and make some attempt to match weights, but going from 39mm to 50mm isn't really practical, I did smoothe and polish the dome, and smoothe the skirt, I kinda wish I got a bit more aggressive, there is about 30gram difference, maybe with the next build, I'm thinking stroker, with a bigger bore, at least 52.4mm, and 44mm stroke, but Pistons are Pistons are Pistons no matter the strokes! Ha..
Was a pleasure talking on the phone today about the stihl 046 build that we're going to do!!! Love all this info that your sharing to everyone even though it makes some builders mad but what the hey can't please everyone hahaha
Thanks for sharing that Harvey. And thanks for taking the time to talk with me about my 394xp they shipped me a new cylinder and piston today. So I’ll be starting over with porting it this weekend.
I’m extremely unhappy with the construction and finishing on the aftermarket pistons and for a while I won’t do a project unless there was a meteor piston to add the more OEM quality piston and the Cabers so that I could feel better about the fact that the most important part of any engine is the piston rings and then the piston... I’ve started doing a couple that the meteor wasn’t available for.., I spend a lot of time on the piston finishing..,. So I was thinking about muffkin’s and how I’m going to get the it vented and I’m then bouncing back over to KenZee’s !!! Channel because I realize that the saw where he’s explaining how you showed him if you use your bottom dead center when plotting your exhaust timing and your tdc that you can actually get a really good visual reference for what is happening in your engine and he flipped back to the page with his 9010 and he was just starting to explain that it was his first so he knows he left power in it and that he should have really ajusted the transfer ports... it’s absolutely critical in my mind know that every saw needs to be added to the reference so that when you are looking over your new projects ...after you have measured the saw and you are looking over your numbers and then you are reviewing how they compare to the other’s models that you have done previous ... then you are getting ready to make your corrections and you review the other models necessary corrections.., Why wouldn’t a group of saw builders not want to document each one and share those spec’s so that when you develop a decent catalog of models .,, I Don’t understand why you couldn’t have a client make a set of measurements..,. We know that we can transfer the measurements to the degree wheel...??? B my muffler is the bell concept with the front face on the 6% curve and after the exhaust leaves the exhaust port it is bounced back off the face and back at the port window... I Completely believe that you can get some resonating waves in a smaller box... I’m trying to figure out why the entire perimeter of a bell couldn’t be open for the most part. The Bell shape... Imagine like a unit about the same size as a red solo cup centered on the exhaust port.. and you basically have a short straight piece of box tube...5”’s I maybe.., you are basically running the straight pipe into your “horn”... in the music game horns and actually more accurate then a speaker because the sound waves can be directed more efficiently..,..unfortunately I have a little piece of 2” box and a little box and I have no way to attach my bell .... without ruining the flow of the air space between my two pieces... the really interesting thing to me is that Mac had done enough research to be able to tell you what length of straight pipe you need based on the cc’s of your cylinder.., Riddle me this one Harvey... why and the hell can’t someone design a piston that is actually shaped so it could help direct the exhaust gases towards the exhaust port window?
Hey Ironhorse, I did a Hyway big bore piston and cylinder swap on a ms440 magnum. Now when i pull the pull rope its hard to pull. When I press the decomp valve, I get one good pull and it snaps back.
I had to go back on the video to see what the initial weight was. I thought you said 94.7 grams and you did, so you only took off 1.6 grams to meet your final weight of 93.1 grams if I read your scale correctly.
I remember years ago I bought a brand new 262xp and a friend suggested we raise the intake side of the piston skirt, which we did and yes it made a difference but I always wondered worried knowing that piston wasn’t in balance
it wont upgrade tubulance to get rid of the skirt on the wristpin orientation like you did ? as i try to understand , it wont ''scoop'' the air like it was or it doesnt matter ? it's pretty amazing what you do , thanks to be here for us !
man you're like the voice of reason in the wilderness , i guess im saying you're a great destress in an insane world. on o google search bent or curved files like those come up everywhere, i had to research stress riser man thats a good tip
Question: So on a 372 XP Torq ... if I do a good job trimming weight from the piston; will that throw my crankshaft "out of balance" - This seems to be the idea out there; but doesn't make sense to me. The crank has its own balance and doesn't care the weight of the piston. In fact on the XP Xtorq those pistons are heavier so any weight should relieve stress on the crank bearings. Thoughts?
Right before showing that buttery-smooth piston underside (well, halfway done!), you mention Re keeping the sides as-thick as front(or maybe it was the rear), wouldn't that be MORE than necessary? Pistons aren't meant for lateral force, just forward/backward, so you should be able to go way thinner on the sides than you need thickness on the front (or especially the back) side of the piston! I'm not saying you need to (or do not need to), just you *could*.... On that note though, you mention weight-reduction in the video multiple times w/ the caveat of "oh I'm not actually aiming for lighter weight" but you speak of it with a decidedly positive tone (and the title of the video..), this is something I wondered about while doing one of my pistons recently (which I'd *never* have thought to do w/o you, and it's SUCH a great move/mod/technique), my only aim was to smooth the heck out of it 'for flow' but I realized just how much material I was removing and knew if I'd weighed it I'd surely have gotten a higher reduction than you did here, even crossed my mind "man I hope this thing doesn't burst" lol, took/take solace in having never heard of such a failure, but yeah I couldn't help but think "Is weight-reduction on the piston actually desirable at all? If so, would ideal weight be near-zero, a piston made of unobtainium?" because another part of me kept thinking "a heavier piston, once in-motion, should help - via centrifugal force - help to make things move faster&easier in that engine", so I'd love to know your 'ideal weight' I don't mean grams just how you'd describe it, are pistons generally too-heavy, would you go with a 1gram piston made of unobtainium if the option were available, etc? Thanks as always, honestly this vid or one of your piston vids, was HUGE for me because I'd only been doing work thinking about port shape/timing/etc, not just overall smoothness-of-flow in the *entirety* of the engine and that's not just 'free power' but it's power that's actually GOOD for your engine (as it's power through efficiency, just like how - conversely - you could decrease power by roughing-up the squish-band, the port-edges etc, it's funny because after 'fixing' a farmertec jug I can't help but think how it's probably equal parts power, and good for longevity, to even everything out!) I think it's probably especially important to consider the combustion chamber, the f.tec squish bands are atrocious, I sanded 13.5thous off one of mine w/o hurting the plating and now it's a big fat band with a slight upwards taper into the chamber, you know other/more popular types of engines so maybe you could tell me that this is already done IE tapered squish bands, I stumbled onto the idea almost by mistake but was watching a video on knock in honda engines (lol,turbo'd honda's) and knock V pre-ignition, anyways they seem of a mindset that "power is made on the line of knock/pre-detonation", and - seeing video animation of how pre-ignition occurs - could not help thinking "if that band is tapered a lil into the chamber, what may have been a pre-detonation can now 'squeeze' its way to the chamber in a way it could not if the squish band were 100% parallel with the piston-top"....would love your thoughts on this, I actually intend to take sandpaper to the inner-edge of my squish band so the transition from it into the chamber is smooth/round instead of a sharp angle like my sanding made it...anyway now that I have a smaller combustion-chamber-dome (because of raising squish-band height, automatically decreasing dome's height & diameter pretty substantially), I look at it and realize that if I went for the same "ideal squish #" as I would've defaulted to, it wouldn't have occurred to me "wow the same squish level means WAY more compression, when your combustion dome is now 70% its original size" lol! I think I'm going to run like 30-35thou squish in this one, will keep the pop-up in there IF its pop-up area lines-up with my new squish-band, have a feeling I'd need a tighter-diameter pop-up "topping" for it to mate properly with the chamber at TDC!
@@theironhorse6600 we just to cutt little bit on the intake side on the piston skirt to gett more fuel on ours old vintake mopeds. it did work fine. just was thinking to that if it does work on power saw too.
@@theironhorse6600 and allso have change to a round crank to fill up the crankcase. its little bit heavyer crank but makes more power sametime. same principal when you fill up the crankcase on the saw.
So I've got a 2 different 52mm 372 pistons and I'm trying to weigh the pros and cons. I've got a hyway pop up that weighs 96 grams and has the double rings the other is a flat top farmertec weighing 90 grams with a single ring. I like the beefier piston skirts and the idea of extra compression on the hyway but having having less weight and less parasitic drag on the farmertec also intrigues me. Any thoughts?
I'm gonna remind you! I want the story! Your life is like mine. I don't expect people to believe half a wat I say but truth is truly stranger than fiction..
hey Ironhorse, just wondering if you have ever ported a 285 CD? I have a very nice one that i found in my neighbors barn. incidently that was the very first husky i ever worked in the woods with back in 1983. i also have a beautiful 394 that i use in my alaskan sawmill and im tempted to send them both to you to spice up!!.. thanks for your great information and let me know if your interested in working my saws. shelby wright, up up upstate NY.
I was starting to write the comment when you put the piston on the scale. Mind reader I have messed with a few pistons and i have had both success and failure. But everytime I do 1 I think about weighing it to kinda balance it so to say. It must have a major effect on those bearings at such high rpm. Wouldnt you say? Everynice video i am still watching just been super busy and haven't been leaving comments
Enjoy your video's. I have an issue and I hope you or someone might assist. I need a 20" Chain saw bar for my Chinese 58cc saw. I purchased a blade that was supposed to work on a 62cc saw but it is larger than my saw can use. Do I have a option other that moving to a 18" Bar/chain combination? I have already 3 -20" chains but cannot use them. Thank You!
If you must go to shorter bar, take existing chains to someone with a breaker & rivet spinner to shorten no of drive links. Keep out take for spare parts for replace odd tooth when hit rock / nail. Save a lot of filing. If do quite a lot of cutting, worth having own tools. Soon pay for the investment, in salvaged chains. A skinflint in the UK.
Thanks for the videos ,I blue up my still 026.the connecting rod at the piston is blue.i will replace the cylinder piston bearing and rings.should I split the case and put a new connecting rod on.beacuse then I'm up to more than I payed for the saw?
Yes we’re getting that same rain after midnight into tomorrow!!! THANK GOD!!!’ It’s so dry it’s scary. We had a couple acre forest fire up country started by a spark off a harvester head hitting a rock. It’s scary dry here in Maine. Work safe IRONHORSE NATION!!!!!!
Haven't watch the video yet I sure will here in a bit. Hey Harvey hope you have a great day today. Anyways when making the piston lighter it does need to be balanced correctly to the crank or it will rob hp and eventually kill the rods bearings and no one likes having to rebuild a saw because they killed the cranks bearings. Most tell me it is not a issue but I will always disagree with that. The life of any engine is a properly balanced rotating assembly. Also less vibration then a unbalanced rotating assembly.
@@theironhorse6600 Hmm interesting I still wonder if balancing it would help hp or hurt it... I know it does prevent vibrations in the saw making for a smoother running saw from what I have done.
Where you outta iron horse what's your 20? Your definitely in the north east like not far far from where I'm borned and raised with that " accent" god bless "
Was thinking lightening up a piston on one of my builds this winter, already being so light im curious if it helps rev up faster and loose the ability to hold torque under load
Got something interesting for you Harvey me and my dad just started rebuilding a 1998 Yamaha 700 VMAX snowmobile that he bought real cheap with no motor we bought a used motor and we tore it down had it brought to a machine shop to be bored got three Wiseco pistons on the way a crank is also in the mail not sure what manufacturer it is but it's a racing crank with rods from the same company a new track and skid components the track were putting on has hundred ninety-seven studs three-quarter Lugs with 1 inch studs also have a set of performance clutches and Hawk triple pipes on the way with stingers she's going to be a mean machine can't wait to see what the dyno numbers are
Nice job on the piston. Factory knows better they just wanna sell new saws.Lol.starting a new job you can cut anytime. Give me a hollar some morning we 'll make a plan.
Enjoy your videos . I my self are old school engine builder . Built many race engines. Now into chain saws . learned a lot whatching you . like what you done to prep the piston . Also muffler mods. I think I heard your a vet I my self served in the Army Vetetnam 1967 1968. 199th light inf.Stay safe my friend.
Thank u so much Mr. Harvey, I really appreciate this more than u will ever know !!! I ❤ u buddy, I am so glad to meet a great human being as ur self, it's an honor to b able to say u r my friend !! And like u said we r just gonna try something with the cylinder and if just so happen it dont work out, then I'll just send u the hole saw and let u start over..🙏 I remember u sayin u like the "blue" 660 and this is one of the new 372 from china it came "blue".. i was told by the main man at farmtec thts now all of the holzffarma 372 r gonna come in he future is "blue".. so if u guys want one of the orange 372's u probably should go ahead an order one of the kit saws bfore thy switch to the all blue one's.. thts just a heads up to all of the great ppl tht is on mr Harvey's channel... good bless each and everyone of u...❤👍 again THANK U IRONHORSE !!
TY TO
4.5???? When it changes direction!!! What a sexy piston!!! I’m so so happy I stumbled into this one....those little ticks and defects on a piston makes me crazy... I started all this curiosity about engine’s in high school when I bought myself a brand new Echo SRM 2501,,, and I had a little bit of general motor knowledge and I was reading my owner manual and it said that every season that you should de-carbon the cylinder if you want it to last a long time... Back when companies wasted time adding quality to their products.., anyway Echo had such a beautifully dished pistons and I was pretty green.., I’d seen a few dished pistons at the machine shop.., the piston in my Lawnboy... was just a regular one piston but boy howdy .,, my string trimmer was juiced!’n😂😂😂
I asked you a while ago , how to work a 372 piston.
I am building my own shop ,and when im finished,i am gonne build an 372xp.
Verry nice movie and good tips.
Thanks Harvy
Greatings from holland
Your welcome Henke!
Since I have started doing this whole reduction in my pistons and the rotational mass total weight and seeing what the overall power increases are possible with just this little modification I’ll be studying the piston and cylinder relationship and seeing where it can be reduced, for certain!!! It’s a fantastic idea for the weight reduction and the timing numbers modification and your only playing with your pistons specific’s!!!
Not watched it all yet but thought I’d say hi to everyone :)
I’m here from a motorized bike group watching this cause I’m working on building a high performance bike shooting for acceleration and top end I was reading in a group I’m in about shaving weight on a piston and some of the benefits this was an interesting and informative video thx man! Enjoying your videos
Edit: my engine is a hybrid saw cylinder with the top chopped off for a cnc billet head to go on for cooling on a China doll transmission that will run a sthil-046 pop up connected to a long rod 40mm stroke
Bless you Ironhorse for sharing your wisdom with us.
I watched this five times so far:)
This is Pure Gold for me to learn how to port a piston!!!
its was 1.7 grams in weight. started with 94.7 and ended with 93.0. still a good job.
Harvey thanks for sharing your knowlege, it's rare in this day and age!
Big fan of your channel, thank sir.
They are called Swedish files. Every gunsmith has a set and I am a gunsmith.
thats what i found, rifle files on a google search among many other names for them
I used to port and polish clylender heads in a machine shop. I think what you are trying to say is that you are eliminating hot spots. When you have ridges it creates hot spots
Yep!
I think my Dad told me it can also create weakness points when one has sharp and or rough finished edges, especially in fast moving parts such as pistons, valves, etc etc
@@theironhorse6600 oil mix ?
@@Sensei948 40-1
Friend, is it enough for XP and X-Torque saws?
Shoe files - they are called Swedish files. Every gunsmith has a set and I am a gunsmith. I have lost a few and broken a few through the years but I stile most part f them. One thing I have noticed about some pistons is the front and back measurements are not the same. One side appears to be taller than the other. I mic them out and sand them until they both are the same height, cylinder top to the bottom of the skirt.
I have the same scale! I just built a scooter top end, with big bore, I bought the scale, because I wanted to compare the Piston weights, and make some attempt to match weights, but going from 39mm to 50mm isn't really practical, I did smoothe and polish the dome, and smoothe the skirt, I kinda wish I got a bit more aggressive, there is about 30gram difference, maybe with the next build, I'm thinking stroker, with a bigger bore, at least 52.4mm, and 44mm stroke, but Pistons are Pistons are Pistons no matter the strokes! Ha..
Was a pleasure talking on the phone today about the stihl 046 build that we're going to do!!! Love all this info that your sharing to everyone even though it makes some builders mad but what the hey can't please everyone hahaha
Thanks Kevin!
I have always cleaned mine up on the edges, Im gonna have to try this. Thank you for all your Hands on Training Sir!
Good advice Harv!
Found it. Thanks!
Learned a lot bud thank you so much for spreading your knowledge. Now I can do the same and my kids can hopefully do the same.
Real nice job Harvey thanks for sharing
Doing it myself is the best way for me to learn. With content like this we should all be able to build saws. Thank you again IRONHORSE 🤙🏻
bin waiting all day!! take care buddy.
Thanks for sharing that Harvey. And thanks for taking the time to talk with me about my 394xp they shipped me a new cylinder and piston today. So I’ll be starting over with porting it this weekend.
Perfect!
Hello Harvey and Ironhorse viewers hello
Thank you for teaching us Harvey the Iron Horse
Hey Mr Harvey good to see you today!
I’m extremely unhappy with the construction and finishing on the aftermarket pistons and for a while I won’t do a project unless there was a meteor piston to add the more OEM quality piston and the Cabers so that I could feel better about the fact that the most important part of any engine is the piston rings and then the piston... I’ve started doing a couple that the meteor wasn’t available for.., I spend a lot of time on the piston finishing..,. So I was thinking about muffkin’s and how I’m going to get the it vented and I’m then bouncing back over to KenZee’s !!! Channel because I realize that the saw where he’s explaining how you showed him if you use your bottom dead center when plotting your exhaust timing and your tdc that you can actually get a really good visual reference for what is happening in your engine and he flipped back to the page with his 9010 and he was just starting to explain that it was his first so he knows he left power in it and that he should have really ajusted the transfer ports... it’s absolutely critical in my mind know that every saw needs to be added to the reference so that when you are looking over your new projects ...after you have measured the saw and you are looking over your numbers and then you are reviewing how they compare to the other’s models that you have done previous ... then you are getting ready to make your corrections and you review the other models necessary corrections.., Why wouldn’t a group of saw builders not want to document each one and share those spec’s so that when you develop a decent catalog of models .,, I Don’t understand why you couldn’t have a client make a set of measurements..,. We know that we can transfer the measurements to the degree wheel...??? B my muffler is the bell concept with the front face on the 6% curve and after the exhaust leaves the exhaust port it is bounced back off the face and back at the port window... I Completely believe that you can get some resonating waves in a smaller box... I’m trying to figure out why the entire perimeter of a bell couldn’t be open for the most part. The Bell shape... Imagine like a unit about the same size as a red solo cup centered on the exhaust port.. and you basically have a short straight piece of box tube...5”’s I maybe.., you are basically running the straight pipe into your “horn”... in the music game horns and actually more accurate then a speaker because the sound waves can be directed more efficiently..,..unfortunately I have a little piece of 2” box and a little box and I have no way to attach my bell .... without ruining the flow of the air space between my two pieces... the really interesting thing to me is that Mac had done enough research to be able to tell you what length of straight pipe you need based on the cc’s of your cylinder.., Riddle me this one Harvey... why and the hell can’t someone design a piston that is actually shaped so it could help direct the exhaust gases towards the exhaust port window?
Hey Ironhorse, I did a Hyway big bore piston and cylinder swap on a ms440 magnum. Now when i pull the pull rope its hard to pull. When I press the decomp valve, I get one good pull and it snaps back.
I had to go back on the video to see what the initial weight was. I thought you said 94.7 grams and you did, so you only took off 1.6 grams to meet your final weight of 93.1 grams if I read your scale correctly.
I remember years ago I bought a brand new 262xp and a friend suggested we raise the intake side of the piston skirt, which we did and yes it made a difference but I always wondered worried knowing that piston wasn’t in balance
Very good one. 😊🌎🌞🍵🍵☕☕
it wont upgrade tubulance to get rid of the skirt on the wristpin orientation like you did ? as i try to understand , it wont ''scoop'' the air like it was or it doesnt matter ? it's pretty amazing what you do , thanks to be here for us !
Man that’s a sexy piston!!!
man you're like the voice of reason in the wilderness , i guess im saying you're a great destress in an insane world. on o google search bent or curved files like those come up everywhere, i had to research stress riser man thats a good tip
Question: So on a 372 XP Torq ... if I do a good job trimming weight from the piston; will that throw my crankshaft "out of balance" - This seems to be the idea out there; but doesn't make sense to me. The crank has its own balance and doesn't care the weight of the piston. In fact on the XP Xtorq those pistons are heavier so any weight should relieve stress on the crank bearings. Thoughts?
Also if the factory did this stuff, you couldn't afford to buy the saw! It would cost 3x or more!
Right before showing that buttery-smooth piston underside (well, halfway done!), you mention Re keeping the sides as-thick as front(or maybe it was the rear), wouldn't that be MORE than necessary? Pistons aren't meant for lateral force, just forward/backward, so you should be able to go way thinner on the sides than you need thickness on the front (or especially the back) side of the piston! I'm not saying you need to (or do not need to), just you *could*.... On that note though, you mention weight-reduction in the video multiple times w/ the caveat of "oh I'm not actually aiming for lighter weight" but you speak of it with a decidedly positive tone (and the title of the video..), this is something I wondered about while doing one of my pistons recently (which I'd *never* have thought to do w/o you, and it's SUCH a great move/mod/technique), my only aim was to smooth the heck out of it 'for flow' but I realized just how much material I was removing and knew if I'd weighed it I'd surely have gotten a higher reduction than you did here, even crossed my mind "man I hope this thing doesn't burst" lol, took/take solace in having never heard of such a failure, but yeah I couldn't help but think "Is weight-reduction on the piston actually desirable at all? If so, would ideal weight be near-zero, a piston made of unobtainium?" because another part of me kept thinking "a heavier piston, once in-motion, should help - via centrifugal force - help to make things move faster&easier in that engine", so I'd love to know your 'ideal weight' I don't mean grams just how you'd describe it, are pistons generally too-heavy, would you go with a 1gram piston made of unobtainium if the option were available, etc?
Thanks as always, honestly this vid or one of your piston vids, was HUGE for me because I'd only been doing work thinking about port shape/timing/etc, not just overall smoothness-of-flow in the *entirety* of the engine and that's not just 'free power' but it's power that's actually GOOD for your engine (as it's power through efficiency, just like how - conversely - you could decrease power by roughing-up the squish-band, the port-edges etc, it's funny because after 'fixing' a farmertec jug I can't help but think how it's probably equal parts power, and good for longevity, to even everything out!) I think it's probably especially important to consider the combustion chamber, the f.tec squish bands are atrocious, I sanded 13.5thous off one of mine w/o hurting the plating and now it's a big fat band with a slight upwards taper into the chamber, you know other/more popular types of engines so maybe you could tell me that this is already done IE tapered squish bands, I stumbled onto the idea almost by mistake but was watching a video on knock in honda engines (lol,turbo'd honda's) and knock V pre-ignition, anyways they seem of a mindset that "power is made on the line of knock/pre-detonation", and - seeing video animation of how pre-ignition occurs - could not help thinking "if that band is tapered a lil into the chamber, what may have been a pre-detonation can now 'squeeze' its way to the chamber in a way it could not if the squish band were 100% parallel with the piston-top"....would love your thoughts on this, I actually intend to take sandpaper to the inner-edge of my squish band so the transition from it into the chamber is smooth/round instead of a sharp angle like my sanding made it...anyway now that I have a smaller combustion-chamber-dome (because of raising squish-band height, automatically decreasing dome's height & diameter pretty substantially), I look at it and realize that if I went for the same "ideal squish #" as I would've defaulted to, it wouldn't have occurred to me "wow the same squish level means WAY more compression, when your combustion dome is now 70% its original size" lol! I think I'm going to run like 30-35thou squish in this one, will keep the pop-up in there IF its pop-up area lines-up with my new squish-band, have a feeling I'd need a tighter-diameter pop-up "topping" for it to mate properly with the chamber at TDC!
I went back a calculated how much weight you actually took off and it was about 2%.
hi. nice work on that piston harvey.
Thanks!
@@theironhorse6600 we just to cutt little bit on the intake side on the piston skirt to gett more fuel on ours old vintake mopeds. it did work fine. just was thinking to that if it does work on power saw too.
It sure does!
@@theironhorse6600 and allso have change to a round crank to fill up the crankcase. its little bit heavyer crank but makes more power sametime. same principal when you fill up the crankcase on the saw.
So I've got a 2 different 52mm 372 pistons and I'm trying to weigh the pros and cons. I've got a hyway pop up that weighs 96 grams and has the double rings the other is a flat top farmertec weighing 90 grams with a single ring. I like the beefier piston skirts and the idea of extra compression on the hyway but having having less weight and less parasitic drag on the farmertec also intrigues me. Any thoughts?
The Duke’s moly coated popup kit is light weight and decent quality for the $30 bucks apiece or what have ya?
You been jeep workin, I see them cut fingers
I'm gonna remind you! I want the story! Your life is like mine. I don't expect people to believe half a wat I say but truth is truly stranger than fiction..
yeh i get told im full of bs for that reason they cant imagine the possibilities in life if you apply yourself.
If it works out on the cylinder I want one and I'm only a few hours away from you
hey Ironhorse, just wondering if you have ever ported a 285 CD? I have a very nice one that i found in my neighbors barn. incidently that was the very first husky i ever worked in the woods with back in 1983. i also have a beautiful 394 that i use in my alaskan sawmill and im tempted to send them both to you to spice up!!.. thanks for your great information and let me know if your interested in working my saws. shelby wright, up up upstate NY.
I was starting to write the comment when you put the piston on the scale. Mind reader I have messed with a few pistons and i have had both success and failure. But everytime I do 1 I think about weighing it to kinda balance it so to say. It must have a major effect on those bearings at such high rpm. Wouldnt you say? Everynice video i am still watching just been super busy and haven't been leaving comments
Enjoy your video's. I have an issue and I hope you or someone might assist. I need a 20" Chain saw bar for my Chinese 58cc saw. I purchased a blade that was supposed to work on a 62cc saw but it is larger than my saw can use. Do I have a option other that moving to a 18" Bar/chain combination? I have already 3 -20" chains but cannot use them. Thank You!
If you must go to shorter bar, take existing chains to someone with a breaker & rivet spinner to shorten no of drive links. Keep out take for spare parts for replace odd tooth when hit rock / nail. Save a lot of filing. If do quite a lot of cutting, worth having own tools. Soon pay for the investment, in salvaged chains. A skinflint in the UK.
Thanks for the videos ,I blue up my still 026.the connecting rod at the piston is blue.i will replace the cylinder piston bearing and rings.should I split the case and put a new connecting rod on.beacuse then I'm up to more than I payed for the saw?
Yes we’re getting that same rain after midnight into tomorrow!!! THANK GOD!!!’ It’s so dry it’s scary. We had a couple acre forest fire up country started by a spark off a harvester head hitting a rock. It’s scary dry here in Maine. Work safe IRONHORSE NATION!!!!!!
They make disposable safety glasses with by focal cheap please protect your eyes
Haven't watch the video yet I sure will here in a bit. Hey Harvey hope you have a great day today. Anyways when making the piston lighter it does need to be balanced correctly to the crank or it will rob hp and eventually kill the rods bearings and no one likes having to rebuild a saw because they killed the cranks bearings. Most tell me it is not a issue but I will always disagree with that. The life of any engine is a properly balanced rotating assembly. Also less vibration then a unbalanced rotating assembly.
Don’t affect 2 stroke like it does 4 stroke!
@@theironhorse6600 Hmm interesting I still wonder if balancing it would help hp or hurt it... I know it does prevent vibrations in the saw making for a smoother running saw from what I have done.
Have you ever tried Cerakoting pistons and other engine parts
Hi
Hey Harvey, did that dolmar 7900/066 build ever get wrapped up? Or did it not work out?
Where you outta iron horse what's your 20? Your definitely in the north east like not far far from where I'm borned and raised with that " accent" god bless "
What's up
What is your opinion on putting a bright polish on the piston skirt and top
Was thinking lightening up a piston on one of my builds this winter, already being so light im curious if it helps rev up faster and loose the ability to hold torque under load
You need to protect your eyes Harvey
What's "what's ap?, up?" Anyone?
Email me Ironhorsechainsaw@gmail.com
Got something interesting for you Harvey me and my dad just started rebuilding a 1998 Yamaha 700 VMAX snowmobile that he bought real cheap with no motor we bought a used motor and we tore it down had it brought to a machine shop to be bored got three Wiseco pistons on the way a crank is also in the mail not sure what manufacturer it is but it's a racing crank with rods from the same company a new track and skid components the track were putting on has hundred ninety-seven studs three-quarter Lugs with 1 inch studs also have a set of performance clutches and Hawk triple pipes on the way with stingers she's going to be a mean machine can't wait to see what the dyno numbers are
Nice job on the piston. Factory knows better they just wanna sell new saws.Lol.starting a new job you can cut anytime. Give me a hollar some morning we 'll make a plan.
Sounds good Tim!