Most likely the circular vibrations were flexing the bellows and causing the needle to move. Much in the same way they will spin out a loose bolt or nut. Not an actual indication of pressure. Try it again, but use a flexible line to isolate the gauge from the saw.
I believe you are correct. When I first looked at the gauge, it was operating as it should, and read just below 5 psi. But then the vibrations broke the gauge. The next gauge will be tubed in and mounted properly to decrease vibrations.
@@austindenotter19 The top cover is divided so that the hot air from the cylinder doesn’t mix with intake air so if you were to drill a hole in the top cover for the the filter it won’t affect the cooling capability.
Ya know, most of the air-over-filter systems I have looked at seemed to be flowing air TOWARDS the fan housing (which would then go over the engine) and would imnfact draw air from the vent holes around the rear handle to keep the filter clean. I distinctly remember the 4910/501 the smoke went from the filter cover area towards the fan housing (tested with a smouldering bamboo skewer)
After building boosted trucks and cars I would say the gauge is affected by the vibrations. The plastics can't hold back that much pressure with no seals and gaskets. Oh and it's more of a supercharger than a turbo.
Very cool video. That saw sounds fantastic! One statement that you made although probably true is technically wrong. You can't automatically assume boost gives you more power. If the boosted air is hotter it can contain fewer oxygen molecules than unboosted cooler air. But in this application, centrifugal fans unload the less air they are moving. So in my estimation the saw has less parasitic loss with boost as opposed to free flowing with holes. Whether any of this amounts to a hill of beans is a different matter. 😅
Why do you and Dyno Joe pull the starter rope out just a little, hold it, then shit the saw off? Never heard a reason why people do that and am curious as to why.
If it is actually making measurable boost, you should try to plumb from the air injection inlet to the carb intakes. It would be a bit more complicated with this being a strato vs a standard style cylinder. You can have a filter screen in the plumbing. Heck you might even be able to open some of the recoil cover vents for more air possibly. I don't have a saw in this chasis or else I'd try it myself
That’s a crazy high Pressure gauge… something that only measures 1 bar or 5-6 psi would probably be easier to see z! It’s just so crazy strong that it blew the whole gauge to Oblivion!!! LMFFAO!!! That’s a freaking awesome little saw!!!
As they say follow the money. Follow the air from the flywheel through the air duct into the carb chamber. As you piston draws down it no longer has to draft relative to boost/turbo pressure. No longer is it self asperating.
in my opinion, if it creates pressure it will be very low, I don't think it exceeds the resistance of the filter, above 30° 35° c when hot, mine doesn't start anymore, I have to remove the cover
The original intent of the design was and still is a pre filter air cleaning assist for the filter chamber/box and of course the filter itself, I suspect that if there is a small amount of positive "boost" it was a side effect outcome and probably not the original intent of the designers. With that being said the story I've heard a few times over the year's was that Husqvarna had a separate design team working on the Jonsered side of the company trying out most of their "experimental" idea's they came up with, like the 630 supers and 670's getting bigger carb's then their early Husky counterparts to give them a little more jam; story goes the Jonsered team came up with the air injection system for the husky saw's and they named the Jonsered branded saw's "turbo". Don't know if this is a bunch of bs or not but I was told this more than 20+ year's ago by a sale's rep from Husky back in the day so who knows. If it's true then I guess it wasn't all marking bs, very nice strong running saw by the way.
It is simply a pre-filtration process. Nothing more. Two-strokes do not perform well with an externally pressurize intake charge. The fuel system cannot adequately keep up, resulting in very lean conditions at high rpm, and very rich at low rpm (loading). That's why top-teir MX engines are not turboed, nor supercharged. Any additional intake pressure of the "turbo/air injection" system is limited by the filter and carburator size. For performance increase an open air filter and bigger carburator would be the way to go. Can it be done? Absolutely, but the tuning would be so rpm-dependant that any change in engine load would decrease the performance exponentially, not to mention substantially increase engine wear. It has been tried successfully, and is more of a gimmick than anything else. Much like the Stihl Jetsaw.
I thought so too. But it is in FACT charged with positive pressure. I have another gauge already on order, and the next test will prove it beyond any doubt. It truly does build pressure and from my feel, the saw is without doubt more powerful since I closed off the holes I had cut unto the top. The next video will silence any and all doubts. Trust in this. I couldn't believe it myself. But before the vibrations broke the gauge, it was without doubt building pressure. I saw it with my own eyes. You will see as well. I couldn't believe it myself. But yes, it is turbo'd to a small degree. Makes sense now why they are so much faster.
@@novicelumberjack I do not doubt it, as it is designed for a semi enclosed intake box. Closing or limiting any engines air intake will always diminished power. Try it with the top cover off. The JRed Turbo system design is to limit outside air, allowing for primarily pre-cleaned air. Without the "turbo" inlet, performance will definitely suffer. It's truly an absolutely ingenious design. I appreciate your testing, and am curious as to the results. However, decades of two-stroke engineering done by multiple manufacturers and thousands of performance have not found any appreciable gains of any air box over surface area. It's strictly a filtration feature... But a dang good one.
@@novicelumberjack I absolutely love what you are doing, and eagerly await your results. But you need a control. Try an 026 or JRed 51sp... Something without the centrifugal pre-separation system. Taking something designed for a system, then sabotaging the system is inconclusive and anecdotal. Break it down logically. If there was any appreciable boost increase from flywheel rpm, the higher the rpm, the more boost.... Forcing higher and higher rpm.. eventually out-consuming available fuel intake...subsequently creating leaner and leaner conditions... it's a simple positive feedback loop. If you let off the throttle the spin-down of rpm would be delayed, and substantial (as the residual pressure would need to be consumed by the engine before the rpms would drop). Such a situation is commonly managed by a boost wastegate. At the very least an RPM limited coil would be required to prevent over speeding of the bearings...as higher rpms would create higher rpms. Because two-strokes are rpm limited by continuously increasing the amount of fuel until there's so much it starts 4-stroking and flooding (more fuel=more oil). Yet the earlier JRed 2071 & 2171 have unlimited coils with the exact same Turbo intake as the limited coil on the 2172. Same part numbers and everything. I have no doubt you will see a pressure increase from the system, as outside air is being blown into the air box. But it's negligible by design. This isn't some high velocity wind being ram-aired into the carb, it's a slight breeze to keep particulates from settling on the filter. Nothing more. Two strokes are very precise systems, and even a tiny air leak can catastrophically unbalance the system. Full race designed dirt bikes, racing ATVs, snowmobiles, nor jet-skis even have a ram-air system, let alone pressurized/charged intakes.. For a reason. Instead, they have large intake surface areas, rifle-bored carburators/throttle bodies, adjustable fuel jets, lightweight pistons, precise combustion chambers, liquid cooling, and aggressive port timing... to make power. Not turbos nor superchargers. Two stroke power is from the exhaust... Not the intake. The design engineers knew this. The vast majority of air being moved by the flywheel fins is dedicated to cooling the cylinder, with just a tiny portion fed into the air box to keep dust and chips from settling. Not to charge the intake. The genius of the system is to keep chips out of the air box, not to turbocharge it. I was with you in the mid 1990s. "Turbo" chainsaw!!! Why doesn't everyone use this? Lol.
@Matt-416 I'm enjoying your thorough write-ups. But there is a "but", and it is a BIG 'ole butt that Sir Mix-A-Lot would sing about... I am getting information directly from a man who worked hand-in-hand with the Husqvarna engineers for five years. This is not me blowing smoke or just taking guesses. This is real. It is turbo'd. The conversation is too long to have in the comments, but EVERYTHING you could say to fight against this has a counter. The more I learn, the more I'm thinking that the Husqvarna engineers are the best in the world.
@@novicelumberjack Had the best engineers? And I positively agree completely. HAD. Husky has completely dropped the ball. Chinese components, overly complicated engineering, poor end-user consideration, heavy, bulky, sealed bearings, multiple crankcases within saw type, no class interchangeable parts, unnecessary multi step auto-tune reset procedures, tin potato mufflers that are ridiculous to modify... And absolutely no innovation. Laughable aftermarket support. Bark box? Intake kits? What's Husqvarna's answer for the 500i? Brand new class of saw (remember when Stihl had no answer for the 365S?). What runs with it? The 585xp? Definitely not the chunky 572xp. Why did Husqvarna design an 86cc saw that's two and a half pounds heavier with under 0.3 less horsepower than Stihl's 80cc saw? Really? Nevermind the fact that a 80cc Stihl is a pound lighter than Husky's 70cc saw. And dimensionally the same. Where were the "best engineers" on that one? 400c? Yup, the Husqvarna 565... How's that weight and power... ?572? Nevermind the ease of Stihl's disassembly and modification. Why do Stihl 80cc felling dawgs fit on their 72cc, 67cc, 59cc, & 50cc saws...? And Husqvarna 60cc dawgs fit in what other model? What's in their pipeline for unreleased models? Stihl has a 202T, a 662, 882, and there's rumors of a 700i coming. It's sad. The travesty of the 576, 562mk1 & 550mk1 is telling. The weights and sizes are a disappointment. The commonality of bearing failure and vacuum leaks are.... Husky HAD the absolute best engineers.
I watched ironpony put 2 holes in the back of a 372xp once, so I copied that on a old 268… you wouldn’t believe how much air comes out of those holes when using the saw, i do believe now I shouldn’t of done that and it’s somewhat force feeding the filter. For sure!
use a flexible line, the bourdon tube (Bit that broke off) is a lot of dead weight on the end of the mechanism, it will probably crack off even on a decent gauge, they are not meant for the sort of vibration a chainsaw produces!
Think what your going to need to do to to keep from destroying gauges is use a piece of the flexible line to the gauge. Don't mount the gauge in the cover it can't take the harmonics of the saws vibrations
Interesting…. I was saying to myself no way in hell it’s making boost not being air tight. Or with many other places pressure can escape from. Maybe I was wrong. Looking forward to seeing the results
Take a piece of paper and tape it over the holes you cut, rev the saw, if paper blows up then the holes are not helpful.. that or use an insense stick and put the smoke at the holes while revving and see where the smoke goes.. I have a hard time believing that its actually making literal boost but perhaps it is at least encouraging the air to flow un-impeded and helping limit pressure drop.. on a typical engine you'll actually see a little bit of vacuum on the intake side when revving, if this keeps from being any vacuum then its actually adding power
Probably. Just like the engine cowling on a small airplane. But you have to have a pressure differential to create airflow so 🤷🏽♂️. No idea how it’s ducted so can’t say it’s creating any intake boost but I’m sure a spinning fan will create a high pressure somewhere.
Interesting but inconclusive. I'll hold off on calling BS until you figure out how to isolate the vibration😁 not holding my breath but would be cool if there's actually a psi or two!
Tree monkey claims turbo means exactly that because a lawsuit. It has to make 2 pounds of boost. I xalled bs but this proves him correct. I literally asked for him to do exactly what your doing.
Bosch is Junk.. Forget the 'German Engineering' BS. Beyond that 2 strokes can only tolerate Very low boost 6 lbs being Max on an engine intended for it. That also assumes the carb can shift to the higher fuel flows required for boost operation.
Most likely the circular vibrations were flexing the bellows and causing the needle to move. Much in the same way they will spin out a loose bolt or nut. Not an actual indication of pressure. Try it again, but use a flexible line to isolate the gauge from the saw.
I believe you are correct. When I first looked at the gauge, it was operating as it should, and read just below 5 psi. But then the vibrations broke the gauge. The next gauge will be tubed in and mounted properly to decrease vibrations.
Get another gauge and attach it with a flexible air hose to eliminate any false readings from vibration. Nice investigating Boedy!!
👍👍Probably best to use a hose to isolate the vibration.
Use a hose and mount it on the handlebar like a tach
Anything with air injection or Turbo is not filtering as well if holes are cut in the top cover.
Or cooling.
@@austindenotter19 The top cover is divided so that the hot air from the cylinder doesn’t mix with intake air so if you were to drill a hole in the top cover for the the filter it won’t affect the cooling capability.
I like the turn to experimental chainsaw ideas. 👍
Ya know, most of the air-over-filter systems I have looked at seemed to be flowing air TOWARDS the fan housing (which would then go over the engine) and would imnfact draw air from the vent holes around the rear handle to keep the filter clean. I distinctly remember the 4910/501 the smoke went from the filter cover area towards the fan housing (tested with a smouldering bamboo skewer)
I completely agree.!!! Poulan’s were the first ones to do that centrifugal or centrifugal air movement to eliminate them fines…
After building boosted trucks and cars I would say the gauge is affected by the vibrations. The plastics can't hold back that much pressure with no seals and gaskets. Oh and it's more of a supercharger than a turbo.
Damn that lil saw is running real good.
Whoopee! Looks like you done got yourself a supercharger!
😂😂😂 did that with my saw once.Compressed air It hit 18,000 rpm. Blew the seals. Stopped. Didnt do it again.
Just my opinion but I think the true intention is to keep the air filtration system cleaner. That's why the Stihls filters plug so much faster.
Nope it's just vibration.
You need a remote mount or at least a oil filled gauge.
😮That's for sure interesting! I hope you can get a definative test result!
Very cool video. That saw sounds fantastic! One statement that you made although probably true is technically wrong. You can't automatically assume boost gives you more power. If the boosted air is hotter it can contain fewer oxygen molecules than unboosted cooler air. But in this application, centrifugal fans unload the less air they are moving. So in my estimation the saw has less parasitic loss with boost as opposed to free flowing with holes. Whether any of this amounts to a hill of beans is a different matter. 😅
Why do you and Dyno Joe pull the starter rope out just a little, hold it, then shit the saw off? Never heard a reason why people do that and am curious as to why.
If it is actually making measurable boost, you should try to plumb from the air injection inlet to the carb intakes. It would be a bit more complicated with this being a strato vs a standard style cylinder. You can have a filter screen in the plumbing. Heck you might even be able to open some of the recoil cover vents for more air possibly. I don't have a saw in this chasis or else I'd try it myself
That’s a crazy high
Pressure gauge… something that only measures 1 bar or 5-6 psi would probably be easier to see z!
It’s just so crazy strong that it blew the whole gauge to Oblivion!!! LMFFAO!!!
That’s a freaking awesome little saw!!!
Is it boost with the air cleaner in the way or is it cooling and reduction of temp.
You should mount it on the bar. The vibration is killing the gauge.
Put a balloon on it, great visual!
Might need to flex mount it so it doesn't absorb the vibrations of the saw....
As they say follow the money. Follow the air from the flywheel through the air duct into the carb chamber. As you piston draws down it no longer has to draft relative to boost/turbo pressure. No longer is it self asperating.
Thats good stuff Boedy! Mount it a bit different and use a hose!
I held a lighter to a hole and it drew air inside while revving. Did not blow it out as boost might. Quandary.
A liquid filled gauge would help with vibration.
I agree that a flexible hose to a remotely mounted gauge would take most of the vibration out of the equation.
Saw runs great.
in my opinion, if it creates pressure it will be very low, I don't think it exceeds the resistance of the filter, above 30° 35° c when hot, mine doesn't start anymore, I have to remove the cover
mount the guage on your arm/wrist, use the small tube that came with guage.
then go find the smallest turbo you can find.
I know guys at my job that can spin the needle on that gauge in both directions.
Try a boost only gauge for an engine that only creates positive pressure no vacuum
The original intent of the design was and still is a pre filter air cleaning assist for the filter chamber/box and of course the filter itself, I suspect that if there is a small amount of positive "boost" it was a side effect outcome and probably not the original intent of the designers. With that being said the story I've heard a few times over the year's was that Husqvarna had a separate design team working on the Jonsered side of the company trying out most of their "experimental" idea's they came up with, like the 630 supers and 670's getting bigger carb's then their early Husky counterparts to give them a little more jam; story goes the Jonsered team came up with the air injection system for the husky saw's and they named the Jonsered branded saw's "turbo". Don't know if this is a bunch of bs or not but I was told this more than 20+ year's ago by a sale's rep from Husky back in the day so who knows. If it's true then I guess it wasn't all marking bs, very nice strong running saw by the way.
It is simply a pre-filtration process. Nothing more.
Two-strokes do not perform well with an externally pressurize intake charge. The fuel system cannot adequately keep up, resulting in very lean conditions at high rpm, and very rich at low rpm (loading).
That's why top-teir MX engines are not turboed, nor supercharged.
Any additional intake pressure of the "turbo/air injection" system is limited by the filter and carburator size. For performance increase an open air filter and bigger carburator would be the way to go.
Can it be done? Absolutely, but the tuning would be so rpm-dependant that any change in engine load would decrease the performance exponentially, not to mention substantially increase engine wear.
It has been tried successfully, and is more of a gimmick than anything else. Much like the Stihl Jetsaw.
I thought so too. But it is in FACT charged with positive pressure. I have another gauge already on order, and the next test will prove it beyond any doubt. It truly does build pressure and from my feel, the saw is without doubt more powerful since I closed off the holes I had cut unto the top. The next video will silence any and all doubts. Trust in this. I couldn't believe it myself. But before the vibrations broke the gauge, it was without doubt building pressure. I saw it with my own eyes. You will see as well. I couldn't believe it myself. But yes, it is turbo'd to a small degree. Makes sense now why they are so much faster.
@@novicelumberjack
I do not doubt it, as it is designed for a semi enclosed intake box. Closing or limiting any engines air intake will always diminished power. Try it with the top cover off.
The JRed Turbo system design is to limit outside air, allowing for primarily pre-cleaned air. Without the "turbo" inlet, performance will definitely suffer.
It's truly an absolutely ingenious design.
I appreciate your testing, and am curious as to the results.
However, decades of two-stroke engineering done by multiple manufacturers and thousands of performance have not found any appreciable gains of any air box over surface area.
It's strictly a filtration feature... But a dang good one.
@@novicelumberjack
I absolutely love what you are doing, and eagerly await your results. But you need a control. Try an 026 or JRed 51sp... Something without the centrifugal pre-separation system. Taking something designed for a system, then sabotaging the system is inconclusive and anecdotal.
Break it down logically.
If there was any appreciable boost increase from flywheel rpm, the higher the rpm, the more boost.... Forcing higher and higher rpm.. eventually out-consuming available fuel intake...subsequently creating leaner and leaner conditions... it's a simple positive feedback loop.
If you let off the throttle the spin-down of rpm would be delayed, and substantial (as the residual pressure would need to be consumed by the engine before the rpms would drop).
Such a situation is commonly managed by a boost wastegate. At the very least an RPM limited coil would be required to prevent over speeding of the bearings...as higher rpms would create higher rpms.
Because two-strokes are rpm limited by continuously increasing the amount of fuel until there's so much it starts 4-stroking and flooding (more fuel=more oil). Yet the earlier JRed 2071 & 2171 have unlimited coils with the exact same Turbo intake as the limited coil on the 2172. Same part numbers and everything.
I have no doubt you will see a pressure increase from the system, as outside air is being blown into the air box. But it's negligible by design. This isn't some high velocity wind being ram-aired into the carb, it's a slight breeze to keep particulates from settling on the filter. Nothing more.
Two strokes are very precise systems, and even a tiny air leak can catastrophically unbalance the system.
Full race designed dirt bikes, racing ATVs, snowmobiles, nor jet-skis even have a ram-air system, let alone pressurized/charged intakes.. For a reason.
Instead, they have large intake surface areas, rifle-bored carburators/throttle bodies, adjustable fuel jets, lightweight pistons, precise combustion chambers, liquid cooling, and aggressive port timing... to make power. Not turbos nor superchargers. Two stroke power is from the exhaust... Not the intake.
The design engineers knew this. The vast majority of air being moved by the flywheel fins is dedicated to cooling the cylinder, with just a tiny portion fed into the air box to keep dust and chips from settling. Not to charge the intake.
The genius of the system is to keep chips out of the air box, not to turbocharge it.
I was with you in the mid 1990s. "Turbo" chainsaw!!! Why doesn't everyone use this?
Lol.
@Matt-416 I'm enjoying your thorough write-ups. But there is a "but", and it is a BIG 'ole butt that Sir Mix-A-Lot would sing about... I am getting information directly from a man who worked hand-in-hand with the Husqvarna engineers for five years. This is not me blowing smoke or just taking guesses. This is real. It is turbo'd. The conversation is too long to have in the comments, but EVERYTHING you could say to fight against this has a counter. The more I learn, the more I'm thinking that the Husqvarna engineers are the best in the world.
@@novicelumberjack
Had the best engineers? And I positively agree completely. HAD.
Husky has completely dropped the ball.
Chinese components, overly complicated engineering, poor end-user consideration, heavy, bulky, sealed bearings, multiple crankcases within saw type, no class interchangeable parts, unnecessary multi step auto-tune reset procedures, tin potato mufflers that are ridiculous to modify... And absolutely no innovation. Laughable aftermarket support. Bark box? Intake kits?
What's Husqvarna's answer for the 500i? Brand new class of saw (remember when Stihl had no answer for the 365S?). What runs with it? The 585xp? Definitely not the chunky 572xp. Why did Husqvarna design an 86cc saw that's two and a half pounds heavier with under 0.3 less horsepower than Stihl's 80cc saw? Really? Nevermind the fact that a 80cc Stihl is a pound lighter than Husky's 70cc saw. And dimensionally the same.
Where were the "best engineers" on that one?
400c? Yup, the Husqvarna 565... How's that weight and power... ?572? Nevermind the ease of Stihl's disassembly and modification.
Why do Stihl 80cc felling dawgs fit on their 72cc, 67cc, 59cc, & 50cc saws...? And Husqvarna 60cc dawgs fit in what other model?
What's in their pipeline for unreleased models? Stihl has a 202T, a 662, 882, and there's rumors of a 700i coming.
It's sad. The travesty of the 576, 562mk1 & 550mk1 is telling. The weights and sizes are a disappointment. The commonality of bearing failure and vacuum leaks are....
Husky HAD the absolute best engineers.
I watched ironpony put 2 holes in the back of a 372xp once, so I copied that on a old 268… you wouldn’t believe how much air comes out of those holes when using the saw, i do believe now I shouldn’t of done that and it’s somewhat force feeding the filter. For sure!
The first time I saw "turbo" on a Jonsered, I honestly thought the saws had turbochargers on them.
use a flexible line, the bourdon tube (Bit that broke off) is a lot of dead weight on the end of the mechanism, it will probably crack off even on a decent gauge, they are not meant for the sort of vibration a chainsaw produces!
Think what your going to need to do to to keep from destroying gauges is use a piece of the flexible line to the gauge. Don't mount the gauge in the cover it can't take the harmonics of the saws vibrations
Interesting…. I was saying to myself no way in hell it’s making boost not being air tight. Or with many other places pressure can escape from. Maybe I was wrong. Looking forward to seeing the results
Take a piece of paper and tape it over the holes you cut, rev the saw, if paper blows up then the holes are not helpful.. that or use an insense stick and put the smoke at the holes while revving and see where the smoke goes.. I have a hard time believing that its actually making literal boost but perhaps it is at least encouraging the air to flow un-impeded and helping limit pressure drop.. on a typical engine you'll actually see a little bit of vacuum on the intake side when revving, if this keeps from being any vacuum then its actually adding power
Take it back and tell them that someone must have dropped it.🤣🤣🤣
Run your saw w/o the cover. They get hot as the dickens. I believe it's cooling not boost.
Probably. Just like the engine cowling on a small airplane. But you have to have a pressure differential to create airflow so 🤷🏽♂️. No idea how it’s ducted so can’t say it’s creating any intake boost but I’m sure a spinning fan will create a high pressure somewhere.
I would put on something and separate from the saw. A hose a and just keep it away from the vibrations 🤷♂️
Well where's my Duct tape at lol
Haha had to do that one time. Had a cracked top cover blowing boost air in my face.😂
stuck a hose to an baloon
Ahead of you there. It will be done.
@@novicelumberjack take your electronic valve from your wheel car.....put ignition ,start the saw.....you didn't see this coming
Interesting but inconclusive. I'll hold off on calling BS until you figure out how to isolate the vibration😁 not holding my breath but would be cool if there's actually a psi or two!
Tree monkey claims turbo means exactly that because a lawsuit. It has to make 2 pounds of boost. I xalled bs but this proves him correct. I literally asked for him to do exactly what your doing.
Yes the 3 series has air injection.
@@kylecromp319so did the 2 series
Bosch is Junk.. Forget the 'German Engineering'
BS. Beyond that 2 strokes can only tolerate Very low boost 6 lbs being Max on an engine intended for it.
That also assumes the carb can shift to the higher fuel flows required for boost operation.
So where is the turbo ? B.S.!!!
No Turbine.
Isolate the gauge from the saw!!!!
Ur mom is turbo charged