People stating things they have no first hand experience with as facts is common practice these days unfortunately. I'm like you and like to actually try things myself before I count it out. Nothing ventured, nothing gained. Yes, it costs you sometimes. But education isn't free. Nice video, have a good one.
well said man... where would we be if everyone just guessed and nobody questioned... this one actually blew my mind tho... for bolt on products this one blows all others out of the water
@@johnscustomsaws I feel sure someone looking for that edge when the first tuned pipe was born was called crazy and it wouldn't work🤷 huge gains with pipes, they aren't made for no reason by any means. I dabble with some cant racing stuff.
@@brennancass3747 i used to build and "race" dirt bikes back when they were all 2 stroke and pipes were a game changer so i feel like an idiot looking back and not realizing that a saw with no pipe at all would benefit immensely from an expansion chamber... one of my many "duh" moments lol
@@johnscustomsaws absolutely, takes a pretty humble individual to even admit they had a "duh" moment. Good on you. None of this is to say stock appearing "muffler" saws can't be fast, they absolutely can. But a well tuned pipe saw of the same variety will whoop on them everytime. There is no secret sauce that can bridge that gap. At least not that I've ever seen.
Perfectly said! I seem to run across this all the time, especially on the internet. Look for an answer to a question and you will get someone's opinion that they present as fact, but with no first hand knowledge. Makes it hard to learn when you spend most of your time trying to weed out all the BS.
@@kevinwatson5076 wow thanks man... i appreciate you guys checking it out and im always open to suggestions... let me know what you would like to see on a video
Dude this video was nuts, I’ve always wondered how the 500 would react to an actual expansion chamber but everyone was always like it won’t work with loud ever having tried it, then you come along try it and blow the stock saw out of the water, this is why your so different you actually will try stuff not just make assumptions. Keep up the great work man and your gonna blow up on RU-vid, your really talented and intelligent.
i appreciate it my man... you wouldnt believe the things i have proven wrong that i just havent posted publicly... its amazing the things that are just considered "facts" that have obviously never been attempted... i could go on for hours about nitrous and 2 strokes... piston support... intake timing... timing advances... fuel and mix oil... and so on and so on... its crazy but i dont want to just come out and disagree with the entire saw community because 70% of the shit they say is not true its shocking... i dont want to seem like i think i know better or something cuz thats not the case.. im just the idiot that blows up saws to find out lol
Some people think about putting a straight pipe on a 2-stroke do you get more horsepower and torque but in reality that is not true. That expansion chamber helps with the flow from the carburetor to the crankcase and that's when the Muffler is the right size then you will get more horsies and more torque. Nice !
Now, find a way to make it fit for everyday use saws, top handle, etc. and you'll be a hero. A very wealthy hero. Although, I'd rock that muffler on my trim saw just the same.
It's actually much more interesting to hear you're surprised at the results of an expansion chamber. Removing an expansion chamber is even more convincing... Braaaap to Blaaah. When you're designing your first tuned pipe don't forget to include the length of the exhaust port. Send Cut Send or equivalent and an expansion chamber app that gives the cones and tubes as a 2D printout makes things easy.
just saw this video im tryin to catch up. too much work. I'm without a doubt building an expansion chamber pipe after watching this. maybe on the 461. or maybe on my 572. probly both. thanx man that opened my eyes also. 👊
I agree with you 100%. Lots of the ideas I have make perfect sense in my head but people keep saying things won't work or are pointless. None of those people have tried it. Definitely going to look at picking up a saw to mess around with and do performance stuff with like this before I start doing it with good saws that have to work.
Hi john, your pipe man does excellent fabricating and welds, a tuned pipe factors in everything, in lenghts, and time /ft/sec. It really is the final piece, its as mind blowing as understanding squish for the first time...
It really pulls the exhaust out. I think Donnie Walker once spoke about an adjustable length tail pipe on one of his expansion chamber kart motors. He could push the pipe in or pull it out for the desired power he needed, all while racing around the track. Pretty smart! Can’t wait to see what you come up with!
thats good thinking... ive heard a couple people say that now and i can totally see that being a good way to do it instead of cutting and rewelding a hundred times lol... good advice man
Get your header pipe built longer than necessary couple it with a silicone sleeve..then trim the header 1\4" at a time and watch the RPMs climb with each cut off the header tube, once you see a drop in rpm from shortening the header stop cutting off length and leave a 1\4 in gap between the header and expansion chamber using the silicone sleeve coupling and call it good..welcome to a tuned exhaust chamber..if you like you can weld in the last cut off ring so its a solid header and expansion chamber combo but not necessary..did it for a decade on nitromethane two strokes running 20,000 or so rpms..they sounded like a robot playing a harmonica.
Tuned pipes are a lot of fun! AuMecanic have done a lot of tutorials, and even some free software to make tuned pipes. Good for novelty toys, but it dosen’t work on a worksaw. Keep up the good work and have some fun! Best wishes from good ol’ Sweden. 🇸🇪 (PS.... I had to subscribe to your channel. 👍)
this will make a huge difference on the NOS saw. looks like it makes the saw "overfuel" almost if you oversize the chamber to the saws cc 🤔🤔👍 Awesome channel keep it up 👍👍👍👍
wow so cool, i guessed it would be quicker only because i’ve ridden motocross bikes all my life, and also if you see any serious saws at GTGs there always piped
Just amazing. I have no real world experience with pipes. I know the basic theory and such. Pretty incredible that it’s not even tuned for the saw and makes that much difference as you said. Maybe the 50cc saws he made them for has similar exhaust duration and runs close to the same rpm? Timing those sonic waves can’t be an easily task. Great video John!
thanks bud... eye opening huh... and yes the blowdown and duration are pretty close actually... i put a longer stinger on it which is what he suggested... he literally told me it would be 30% faster at lest and up t0 40%... he was right... thats crazy for a bolt on mod!!!
About what I'd expect from an expansion chamber. Don't be afraid of lots of exhaust duration with expansion chambers, allosw that charge to be forced back in.✌️
Love that sound John! Expansion chamber tuning has a lot to do with cylinder pressures at certain rpm. If you can get the parameters right, then the resonance from the expansion chamber will build pressure just as the exhaust port is closing. Not much application for tree work, but it would be great for an Alaskan mill setup.
can you explain why you say good for milling, John previously has said not to port a saw if it's going to be used for milling, at least. But maybe not applicable to muffler I don't know. The awkward muffler is not practical for anything except showing it off and testing, the muffler shown would always be in the way and major burn risk to body parts etc.
@@livingadamman7994 A lot of porting work makes more power at a higher RPM than stock, and that would not work well for milling. My 3120 is ignition limited to a pretty low RPM compared to most saws. The stock exhaust is really restrictive also. My Alaskan mill setup is already bulky and awkward to handle, so adding a pipe wouldn't be as intrusive as having one on a normal use saw. I know it would be a lot of work to get everything right. Most two-strokes can make more power with a tuned pipe instead of a box muffler. Call it a pipe dream. I just think it's cool and sounds amazing.
@@TimberTrainer Thanks for your thoughts. I have a 500i with Egan SS. Buckin has a new header pipe coming which Mark is developing with Buckin's R&D and I think it would beat the Egan SS for my saw. The expansion muffler in this video of Johns is indeed impressive, and theres so much to be understood about it. I can tell you that the pulse bounce back to exhaust port on cylinder would help as far as keeping pressure stopping unburned fuel to exit chamber, however the downside with said is if pipe harmonics are not in perfect balance exhaust gasses flow back into the crank case causing extra heat and hence degrading the life of the saw, and compromising performance. Remember 2 strokes are air cooled and make a lot of heat, that heat needs to get out as mentioned, theres a downside to everyting.
@livingadamman7994 Good point about the heat. Most engines with expansion chambers are on water cooled machines. It might also require ear plugs and muffs to be tolerable running in your face for hours.
I've seen dyno testing that proves that (on certain saws) you can gain 60% or more horsepower from a simple expansion chamber pipe.. some seem to not respond as well but the saw dyno is a newer thing and theres only limited testing thats so far been done
If you look at the rm85 it puts out 22hp. Thats on a motorcycle. Which has to aurgueably a wider powerband than a chainsaw. The narrower you can make the powerband the more hp you can make. You can double the hp of a 2 stroke with a tuned pipe. So if you are making 8 hp with your 70cc class saw then 16 hp with a pipe. Probably not for long on gasoline though, most likely not enough cooling.
now just need some bean oil, and it would smell, and sound like the flat track, and motocross races did to back in the 70's, and early 80's. If anyone has been around two stroke dirt bikes, are street bikes, and actually rode performance bikes even built for consumers factory high end bikes. Then you should know two stroke bikes with the performance exhaust walks away from anything with non tuned exhaust like it's sitting still, and that goes all the way back into late 60's over here. Same thing for hot saws in the timber events, and why wouldn't every two stroke on the market chain saw benefit from tuned exhaust, because they're no different than performance saws, are the few dirt bikes that are still two stroke....
2 stroke engines get (or loose) 30-40% of their power due to the exhaust system. I have been playing and building 2 stroke engines (as a go-kart racer) for over 40 years now and you can get on a 2 stroke racing engine over 400 HP per 1000cc equivalent.(a TM k10 125 cc shifter kart engine has over 50HP out of the box before tunning). Of course if you want longevity you have to detune the figures but still you could get with mods 7.5 HP out a 50cc engine. I am new to chainsaws but I know my way around 2 stroke engines and I will tune up a chainsaw but the problem I seem to face is that chainsaws don't have a separate cylinder head and that is critical. Are there any chainsaws with separate cylinder head?
This is amazing to see side by side. It makes me wonder if there might be a cunning way of scaling down an expansion chambered pipe to something you might practically use day to day (or situating it in such a way that it doesn’t impede manoeuvrability in a work setting). Sounds bitchin!
Im picking up what you are laying down my man... I immediately thought the same thing once I seen the results... it would be very difficult to get the full potential without having a big pipe but even if a guy can get 50% and downsize so its practical... I think people are forgetting the side by side was done with a pipe vs a dual port custom muffler and it blew it out of the water... wasn't racing a stock muffler
may I please ask you. I have an MS381, WHAT OVER SIZE BIG BORE COULD I FIT TO THIS, JUST USEING IT AS MY PLAY HOT ROD SAW. I LOVE WATHING YOU, love how you are NO BULL SHIT type of guy. you keep it real. don't ever change. The haters are just Karran's!!!!!!
it wouldnt even run lol... i had to hold it wide open on startup and swap the butterfly valve in the throttle body with one out of a 661 (or i could have drilled out the stock hole)... the saw was soooooo rich at first even after i swapped the valve it wouldnt idle until i ran it for a bit... so that shows that the guys saying it will run too lean were totally wrong... great question man... i forgot to mention that
Donny walker out Canda talk abt them. He does work on them and Husky. Most talk bad but like anything it the new. Once more none dealers can get software. I think we'll see some new stuff get crazy.
I think it be cool see like holley with there fuel injection system. Get into the saw game and people know these systems come up with some crazy stuff.
@@SOHN32 i have the software but i will let you in on a secret... it does njothing!!! sure it tells you WHAT the system is doing and history but you cant change anything... i cant say publicly yet but i have the answer and it has nothing to do with programming... its such an obvious answer that i cant be the only one thinking it... i was typing you a hint but i cant even do that it would give it away
@@SOHN32 i agree... but i dont think they will unfortunately... too small of a market for them... it would take a small time guy in a tiny shop in Minnesota or something im thinking
Just a local guy he doesn't sell em or anything just makes them for himself and I bought a couple used ones for his 50cc race saw... throw away pipes honestly so I can't wait for the proper pipes he makes for the saw I can't imagine
