DRILLING HOLES IN A PISTON?? SERIOUSLY!!

[@harrybrandt2462]

I'm glad you're still liking doing chainsaws on KZbin, Tinman. Cause I'm not done learning. I hope you don't get tired of it for a long time..... 👍

[@tinmanssaws]

Glad you're here, I'm still having fun!!

[@aaronpowell4885]

Learned this trick from my buddies dad who was a pretty well known 2t dirt bike engine builder in our area! Still yet to employ it on any of my saw builds. So fortunate I had the opportunity to shadow him!

[@jeffdillard8789]

What people dont realize is that the exhaust bridge when it gets hot, it will swell inward and can really dig into the piston and rings. On tbe older dirt bikes that had a cast iron sleeve we would sand or grind on the bridge to make more clearance

[@jd70harryharris80]

Done this for years on my old dirt bikes 🤘

[@tinmanssaws]

Dirt bike guys know about this for sure. That's where I got it from....a dirt bike guy.

[@tomintexas817]

sweet I have a dt250 that I want to play with after I get porting down only have 2 saws left a48cc and a 111cc so after the later I think I'll be ready😅😊😂

[@mobiletech6289]

Standard protocol with a wiseco piston - drilled many a piston -the guys that thought they new better and didn’t scatted top ends a few hours later

[@I_Dont_Answer_Questions]

done...

[@EarthSurferUSA]

Not for cooling, but for lubrication, like at an exhaust bridge. I transform small piston port engines to reed valve engines where I add a 5th transfer port on the intake side of the cylinder. Because I lose bearing surface, I have to add oil holes/grooves to be able to survive my dyno. Let me guess what old dirt bike you did it to first. 1970's Elsinore 125?

[@Esau_1967]

Yamaha has done this in 2 strokes since the 80s! It works! Great idea Tinman!

[@charleswelch249]

I have always wondered how to improve a 2 stroke engine. Thank you for sharing your experience with everyone.

[@steveroberson1979]

Thanks Tinman 4 sharing this precious info! I just put a new top end on my 562xp did some lower transfer work and polished the exhaust port. I'm running a Steadfast performance muffler! Shes a real ripper! Definitely gained over stock. But gr8 info 4 when I decide 2 rebuild a vintage saw!

[@JackScott-v2y]

Thanks for the info because I’ve got a Poulan that’s been getting pretty hot. Keep up the good work man I appreciate your help, knowledge and advice.

[@StihlRunnin]

Stock muffler?

[@JackScott-v2y]

No I put a 3/4 port in and gutted the baffles out but ported it also. Poulan 3400

[@StihlRunnin]

@@JackScott-v2y okay then I got two ideas without having seen the saw or anything, one is that I’d want full skip chain, even with the little bar, clears chips, pulls fewer teeth in the kerf and keeps your rpms up. Isn’t asking as much from the drivetrain and crank that way. If you’re port work made it peaky it may not want to lug a full comp short bar, I’d do whatever the longer bar and chain setup was for those, probably close to 30” came stock so whatever fits. If it’s not how you’re running it then I’d cut the plastics or drill holes in some key areas and try to get it to pull air across the fins and especially the base of the cylinder, that area can get heat sink from the top end and it’ll basically be heating the air and fuel that’s going into your engine because your bottom end is soaking up heat. If you can get cool air into the intake that could help too

[@JackScott-v2y]

@@StihlRunnin thanks for the info I’ve tried a skip tooth it helps but haven’t tried putting holes in the plastic yet. I’m probably going to put the oil journals in and a few holes in the plastic too. More air and oil for cooling the better off is what I would think.

[@JackScott-v2y]

I’m also trying going from 3/8 too .325 too see if that helps any.

[@sandsock]

Probably the greatest feature of the new saws is the see through gas tank. That fuel tank acts like a radiator and helps cool the saw, a little. Dont ever just run your saw to empty, hold that saw up after 15-20 minutes and see how much fuel you have left. Set it down and let it idle to cool , go drag some brush , move some logs. Refill more often than not

[@StihlRunnin]

Very true! Got to give em room to breathe. And I don’t ever shut off a hot saw, good way to give yourself problems.

[@garychandler4296]

We would let the saw run free a bit at a high idle to cool if we thought it was hot when firewooding.

[@glennwmurphy1]

very cool! i drilled my 925 cases and now i'll do the piston. still looking for crank bearings. THANKS MUCH, TINMAN!

[@EarthSurferUSA]

Try "Detroit ball bearings" (company). You need to know the OD, ID and width of the bearing, along with the rpm you will have, and any special radius on the OD or ID of your stock bearing races.

[@Magoot2456]

Been waiting on this video for a long time! Ive heard you and the Ironhorse talk about this, but never done it on video. Im definitely a visual learner, if i actually see something done i can understand it way faster than someone explaining it :) thank you for this video man! Much love from Oregon to Tinman and family :)

[@gregbeck906]

Thank you for this free knowledge my friend! 👊

[@brackenprofaizer2601]

I sure do appreciate all your tips and tricks. I sure do love my flex volt Dewalt tools!

[@CharlesBrisco]

I use small round dimond ball bits to chamfer the holes when I put them in pistons but drill bit works too i like to taper the wrists pin holes on a larger taper too lota ways to achieve the same goal have a good one

[@StihlRunnin]

That countersink is a huge deal! I’m awful careful with edges and burrs because I’ve had a couple little projects hang up on me. Makes for a short run.

[@EarthSurferUSA]

I use those smooth (no Flutes) diamond impregnated cutters to champher ports, (after porting on a little CNC mill), and then cratex rubber abrasives to smooth out the cut plating edge. They work great. You might think the aluminum will clog up the diamond cutter, but it doesn't.

[@EarthSurferUSA]

You can drill the holes (under the ring), anywhere on the piston as long as the holes do not traverse a port, (holes where the cylinder wall is there for the stroke, between the ports).

[@martyrutter3630]

Who would think that this would work, but if you say it does that is good enough for me. 😂

[@texasmcgyver]

Very interesting info! 🇺🇸💯

[@welshwizard822]

Good vid TinMan, I wondered for a long time why no one has mentioned this on saws. It was common on dirt bikes back in 80's I'm like you old school......but older😅 happy new year to the family 👍🏴󠁧󠁢󠁷󠁬󠁳󠁿

[@yveslarose6249]

Thanks for sharing this with us. 😊

[@dirtcurt1]

Interesting subject that also occurs in aviation and Volkswagens. In aviation it’s pure math, air is forced in and down through the cylinders. Only so much heat transfer can occur. In an airplane, the heat transfer is a fixed amount, and you can make huge gains in hp building a motor, but you can’t always use it. The interesting thing is that in an airplane you can climb to altitude where the air is thinner and cooler and normally aspirated engines make less horsepower. So a 200hp engine at sea level will make 100 hp at 10k feet. You build a 300hp (in the 200hp) engine and at altitude it makes 150hp. That’s still inside of the 200hp sea level heat transfer. These are example numbers. Turbos also help at altitude, but you still run into the same problem of heat transfer. Aviation is all about the numbers you’re allowed to run set by the manufacturer. In theory, you could build a hot rod saw for high altitude in the same manner of operation (if you live at high altitude). I knew a mechanic that owned a used car lot next to his repair shop in Los Banos California. His main inventory were Volkswagens of all kinds. I asked him why. Well, Los Banos is about an hour out of the Bay Area and the hippies would leave the cool Bay Area and put the hammer down and go 80mph on Interstate 5 when it was 105 degrees. Without additional cooling, the air cooled motors would blow up at those hp settings. He would give them an estimate, they would say “no way man” and he would make an offer on the car as is and he made a good living.

[@SomeGuysSawShop]

That’s some old school stuff, drilling holes in pistons to keep temps low, and to get a tiny bit more compression we drilled holes in the crown to the ring land as lateral gas porting

[@tomintexas817]

Tinman I ported my 020av it has the piston sideways like that one the wrist pin was caped on the exhaust side just like you did pretty sure your fine

[@garychandler4296]

I recall this trick from my firewooding days, but there was another way to drill it for more power, but we didn't do it because we needed reliability.

[@MegaKelcat]

I remember doing this years ago on a Bultaco 370. The manual actually called for it on bridged cylinders.

[@BrandonBigB956]

Use a sharpie marker instead of the scratch lines and less clean up when done.

[@fast4405]

Alot of older arctic cat zr 440 race sleds had those holes for oiling the bridge. Will work just great!

[@sydrider6023]

One way to cool a two stroke piston that is under it’s maximum load for a long time is to hit the kill switch for a short time. I wonder how a chain saw would react to that. You keep the throttle fully open but you stop the spark plug from lighting the mixture for a short time.

[@steveriggenbach90]

I’ve never heard heard of this. Thanks for sharing this. Maybe show in your cutaway.

[@mattw5729]

Outstanding, thank you Sir! Absolutely enjoy learning from you!

[@tinmanssaws]

Glad you enjoyed this video.

[@randymorris8371]

Good information good video! Thanks for sharing

[@boriss.861]

Tinman what size drill bit have you found is good to go?

[@ronsilva516]

Makes a lot of sense 👍😎

[@jakegorman7121]

I have an antique saw that I cannot find rings for and it was a little low on compression so I drilled some tiny holes to gas Port the ring to help it gain compression for a little while longer.

[@stumpymcgivons1042]

Maybe try drilling it out like a chunk of swiss cheese. I'm guessing you would lose torque but gain throttle response and high RPM HP. It may be a beast on top! Thanks for the great videos

[@rickhamm3962]

Was wondering what would be to hot for a cylinder head versus normal temperatures? Thanks for awesome video's.

[@thebradleysoncatbirdhill6849]

Any time you begin a video with...." this is the first time I've ever done this on the channel", you can pretty much guarantee full watch from everyone!!!👍👍👍

[@wrstew1272]

What- people don’t watch this guy till the end? Probably the ones who don’t click the button, you know the thumbs up button 😢 😮

[@martyrutter3630]

Who is not watching the entire video, I want names 😂😂

[@primarchxi6639]

I saw this trick a few months ago on a dirt bike and i was like WTF!!?? And immediately i was wondering if we can apply this to saws, so im glad to learn that we actually can! What benefits we have (if there is any), if we do this on a stock saw?

[@stephenwilson1649]

Hi tinman,,,good techky info...thanks hay..

[@davidcarpenter8741]

I have seen something like this on 268 pistons. On the two bores that hold the piston pin, on the bottom side, each bore has a notch that looks like it allows mix and air to contact the ends of the needle bearing. Take a look!

[@tinmanssaws]

Interesting, need to look through my pistons and find a 268 piston to look at.

[@davidcarpenter8741]

​@@tinmanssawsms660 piston also has this

[@bigmoustacheal3295]

Wow! Never saw that before. Makes good sense to me. That should work on a stock saw....?... Thanks again!

[@EarthSurferUSA]

3 kinds of cooling. 1) Water cooling 2) forced air cooling with a fan (for example, chain saws) 3) free air cooling (snowmobiles and bikes with out water cooling or forced air.)

[@TRUCKERMcD]

Tinmans hole will go down in history! 🙂

[@tinmanssaws]

Too funny 😁

[@martyrutter3630]

😂😂😂

[@barney1941]

sorry dude I had a rough day. however the MIGHTY VAC 8500 comment stands!

[@camrynrhodes798]

Thanks 👍

[@tdawg8605]

I was thinking why not drill a smaller hole that is tampered out like a spray nozzle to disperse the fuel mixture more. Maybe except at the exhaust bridge. Just thinking out loud. Interesting though, never saw this done before. Good stuff. TC Mahalo Tinman 🤙🤙🤙

[@rjc9000]

Hey tinman do you think this would help from alot of saws scoring the piston on the exhaust side. Ive also been told to let the saw idle for a while after running it hard to let it come down to normal operating temp. If not ive been told it will heat soak into the coil and lead to premature failure.

[@CoryHorton836]

i might try this on a homelite sxl or xl-12, i have a couple that need pistons so that will give me a chance to do some performance work.

[@psychoholicslag4801]

I coat V8 gas motor pistons with ceramic heat barrier along with the itake and exhaust ports and the combustion chamber. Works great and is very durable. Has anyone tried coatings on two stroke air cooled engines?

[@tinmanssaws]

Some of the higher end pistons for chainsaws have a coating on them.

[@meskalin64]

Why is the piston pin towards the intake? I thought they were 90 degres twisted.

[@rodneymiddleton9624]

Thanks!

[@alvinmcdonald390]

Greatttt What’s the diameter bit did you used to drill that hole?

[@OldcampRanch]

I have 10 saws, all of them are bone stock, I have absolutely no problem with any of them, I’m concerned that modifying them will hurt reliability, what say you?

[@billhacks]

Mild mods won't hurt a thing. Some will actually help. Things like mild muffler mods help them run cooler. When it comes to port work, if you are very conservative with it, it won't hurt reliability. It is surprising how much difference it makes to simply clean up things will make.

[@tinmanssaws]

When you modify any engine you do run the risk of a failure. But honestly I don't notice any detriment in longevity on ported saws as long as they are built properly and are run sharp.

[@joracer1]

On my saws i let them 4 stroke on top end when in no wood to light load. Is that ok. Will that help?

[@Bg1111ghk]

You have 10 saws, you can afford to potentially compromise reliability on 1 of them.

[@rjc9000]

This is a common mod on dirt bike pistons to help cool the exhaust bridge.

[@chrischris3222]

What size holes ?

[@achristodd]

Many moons ago, in my motocross days, you saw this all the time, and IIRC, the holes were stock on some engines. Those bridges would for sure get hot.

[@lehibell6176]

I have several done this way😊

[@maxwebster7572]

solid

[@stickyricky9612]

I have that hoodie, prairie boy Canadian Tire special.

[@jayborchardt4742]

I have an odd question. when you have a ported saw, does it ask more on the crank seals? I hope you know what i mean.

[@tinmanssaws]

Not that I've noticed

[@matthewbeaver5026]

First off dont run it all the way empty. Soon as it starts to die. Shut it down and fuel it. Dont introduce air to the lines. If you had it clear empty. Pull the plug. Pull the starter rope 10-15 times to 'prime' it. Reinsert plug. And start with normal starting procedure. Maybe skip the full choke pull if you know you got fuel from 'priming' On a normal cold start up. Follow sthils intructions to a T. Full choke. (Decompression if you have it) pull starter cord til fires Half choke pull til starts. Very thorough starting procedure videos available.

[@brentmorton7609]

I have a p42. That runs. If you want it?

[@tinmanssaws]

Thanks for the offer but I have like 6 of them now I think I'm good to go.

[@darrellmartin4242]

I got a question for you I don’t know if it’s a dumb question but could you take the 850 and send it to wolf creek or somewhere that makes cylinders and have them to re-chrome it

[@wrstew1272]

I’m sure that Wolf Creek is not building cylinders. It’s quite a complex, equipment extensive, precision machining process 😊. It would be far too much for an independent shop to make these parts on the small scale that exists.

[@wrstew1272]

The issue of the aluminum button, is it behind the circling? Is there any way on earth that the button could escape? Aircraft engines routinely use similar “buttons “. with zero impact. Don’t worry, Be Happy 😂

[@darrellmartin4242]

But isn’t dyno joe having cylinders done I’m pretty sure he has a company doing them for him

[@Connor33558]

yeah Ive seen dyno joe bore the cylinders and add a cast iron sleeve, he might also be replating them

[@michaelsimpson9779]

Only stupid question is the one you didn't ask when you had the chance.... you don't know what you don't know. 👍

[@tona6g72]

I should do this to my Sthil 036

[@kdrweld8518]

What size hole you use? 1/8”?

[@tinmanssaws]

Smaller then that, like 1/16 or smaller

[@jakegorman7121]

It's in the middle of the exhaust Port it is going to get a lot of fuel through there....

[@keemez]

Ith thith guy in the thame general vithinity ath Andrew from Eathtonmade?

[@Dcale]

Also, the bridge must be dished It is not supposed to be the same inside diameter as the rest of the cylinder

[@SepticWhelk]

Air cooled aircraft motors have very much more tapered machined fins ? I could do that on the mill .

[@kevinz763]

Hey Tinman, I sent you a email you might like to have intrest in on head intake dimple testing. There's a link in there to a video of testing on it. Keep up the vids

[@MotoGPlay-b9f]

Hello, I don't komprehend why people working with motors don't komprehend to work with vapor. If you are putting in tons of gasoline that doesn't burn let alone implode you are holding heat in that mass. By accident I dis-covered in the 70's that you kan run a small motor on exhaust without the muffeler and carburetor after starting. The other side is If you build a motor with cheap design then you will have problems with heat. What happens if you build with iron or steel and have a water jacket and then use that water in the motor and have a real ignition system instead of everything re-verse designed after killing and stealing the items to make an kontrol an economy by and forbtge murders? How do you explain the 1950's patent secrecy act in America. We lost the war to the romans(the nazis,, the holy romans, in bed with rothchilds, is rah ell, egypt, arab, sumerians, asia, affs, and south of the border, greek( oh, you mean the romans). There was flexible glass invented alleged by an italian and he took it before cesar ? and he was killed bekause it would disrupt his economy. Jordan Maxwell, it's all roman.

[@MotoGPlay-b9f]

This was a 4 stroke motor that was aluminum or other non-ferrous metal, possibly a briggs and stratton.

[@barney1941]

if that is the case what was M-tronic and AUTO-tune made for? a 4 cycle liquid cooled engine is way different than a 2 cycle air cooled. I'd put the drill down and maybe invest in a MIGHTY VAC 8500 just sayin

[@barney1941]

maybe a fine tip sharpie???

[@madmarkstoys]

Don't you just love 2 strokes

[@longbar105d]

👍

[@alltherpm]

Lrb pistons are soft compared to original pioneer material

[@tinmanssaws]

I think I'll.heat treat this one for that reason.

[@wrstew1272]

@@tinmanssaws. Please review the process for heat treatment on the piston, it’s not talked about enough. 😊

[@mikahakkinen5651]

oil doesnt cool the piston its the gas cooling down down piston and cylinder.

[@ronwade2206]

Race cars have veey light Pistons and those pistons have holes, a lot of holes! Formula 1 Pistons have No Skirts.

[@jimwuytack4738]

Talk to some old GoKart racers ..

[@MochamadAlisona]

sorry, can I ask for a telephone number, because I am in Indonesia and have a Sthil 026 which is very difficult to start, and here the Sthil workshop is being repaired, then I used it and ran out of fuel, then it was difficult to start, even though I had given fuel to the carburetor, Until now it's been very difficult to live Please help me

[@dalehulst4518]

Tell me more secrets

[@kurtsteele5587]

Hows the tinman and family