As you know I've been a subscriber for a good while and never got round to saying thanks. Back in the day when there was no internet about the only option was guidelines in books followed by trial and error, anyhow I discovered a lot of things which worked but only had my imagination to figure out why/how but now I'm findin out for real the how/why thanks to you Dave. Regards Roy
Hi Roy, cheers for the kind words 😀 Same here, books and that was about it for me. I remember hearing about the Internet for the first time on John Cravens News Round when I was at school.
@@AutoBeta2T If you want I can send some vids for plotting expansion chamber templates old school style, basically a school geometry set, tape measure and a strip of cardboard (or similar). For most people wanting to make their own but don't have the software or like me just don't get on very well with computers. Yeah, it's primitive but how did Walter Kaden made the MZ ones back in the 50s or 60s? It wouldn't be precise enough for the Aprillia gp team where they chase every half a horsepower but for someone who just wants an upgrade on their street bike it's close enough, after the cones etc are rolled and ground flat for welding the error is prolly plus or minus a millimeter The vids were made for a freind but if you want them they're free to use, I just don't want the knowledge to die. You'll have to do a voiceover tho, my Geordie accent is pretty thick.
@@AutoBeta2T Computer printouts are more accurate obviously but if you're cutting the metal by.hand you're only ever gonna be plus or minus maybe half a millimeter anyhow and add to that some distortion if you're a bit too brutal when you're rolling it.
Good to see you're still diving deeper and deeper down the rabbit hole with this engine, these videos, like the early 2strokestuffing videos, will prove to be a treasured source of information in years to come. Thank you for sharing your findings.
Ive just come across your channel possibly by watching 2 stroke stuffing, but as a 16 yr old i had the autisa 93cc on my AR, i machined my head to lower the compression as i could never get the head to seal, I only got it to run right for short periods and never understood 2 strokes properly, but in 1998 YT didnt exist and i never had the funds for a tuner and so long as it got me to the training school i was happy ish, great content and many thanks as I yern for another try.
Nice and complicated =) I usually actually go much easier way(deciding portsizes and timings), i just go by measurements and what available to acheive inside physical borders. You got rules set by pistonring and so on and so on. You also got rules set by blowdown duration. (That '30deg' rule is a physical border) Looking forward to next update, keep it up =)
Two stokes are part technology and part witchcraft, the technology points you in the right direction then after that, , , , If you want them I can send some vids I made for an Internet friend for drawing out expansion chambers old school, no computers, no printouts, just a school geometry set, tape measure and a strip of cardboard, It's prolly how Walter Kaden made the MZ ones in the 50s or 60s, not accurate enough to chase the last half of a horsepower but more than adequate for improving your street bike. Assuming you can calculate the pipe length and cone tapers in the first place. You'll find that in the books Dave mentioned.
Cool 😎 It was the first two stroke book I owned. I must have been 16, I recon? Mine has been well read. I did think it could have gone into pipes a bit more but an excellent read.
@AutoBeta2T I agree about the exhaust section. I did find some calculations for 2 stroke exhausts. I can't remember where from ,it was over 30 years ago 😊
Very interesting! Would you say this measuring method you're using here could be utilised with car heads flow testing? What are the Hti Manometer measuring? Is there a way to measure the air speed?
Hi, I'm not sure if it could be used on 4 strokes? The software wouldn't, but I guess the pressure readings on the manometers could be used to show a change in flow. The manometers are measuring pressure at the entry to the venturi and the delta between the entry and the throat. The software used this data along with anbient pressure and temperature to work out the flow time.area. So it should be calculating mass flow at each piston opening I believe?
Not sure exactly what your question is but you measure flow rate at different valve lift rates. Meaning on a flow bench. Build prostock nhra engines. But never tested with piston in different locations don't know how you would do that typically the flow bench is sucking from where the piston is located
Got to say this is one of the few channels I have come across where I can't find anything to pick at LOL. Serious question though, what kind of gain would be achievable with say just a bit of moderate port work and then winding the compression up as far as possible along with some octane booster in the the fuel? (volumetric efficiency vs thermal efficiency) Thanks.
Hi, cheers, and I'm pleased you are enjoying the videos. The ports are already fairly maxed out from standard but still have some more to go, I think - that will come. Next up is compression, but I plan to go lower first as more energy in the pipe in theory should help... but if that doesn't work, then I'll look to increase it higher. I want to do the 100mph on pump fuel, which is 97 - 99 octane as per the original chalenge but until I can do some real world runs I won't know if I can get away with it.
@@AutoBeta2T Understood with the challenge. I have only picked this up somewhere in the middle so wasn't aware. Back in the day I started out with a GP100, disk valve and all lol. Shall watch with interest 👍
Hi, first of all, you're doing a really good work, keep it up!!! I'm also using Engmod2t, and I wanted to use it to create a tuned exhaust, but I'm a bit worried as the results in the program are good, whereas I don't know how it will perform in reality... Did you ever try to build an exhaust with its data? Also, did you ever check how your pipes perform in engmod compared to reality? Thanks for your time if you read all of this, and good luck for the growth of the channel! 😁
Hi Jacopo, cheers for the kind words 😀 Regarding exhausts, quite a few that were designed in EngMod2T. The results were always good, but note that I always started with a known pipe that had been dynoed and I have a curve for. I then worked in the sim to improve on it. I always seemed to have good results. The sim doesn't necessarily match the dyno readings especially if the runs are done on a inertia dyno (endmod is more like a load dyno) so the pipes may peak at different rpms compared to the dyno but if you measure accurately the generally an improvement in engmod will give a improvement in reality. Cheers, Dave
Hi Cliff, welcome to the channel 😀 Yep, as you say, what I am doing here is not representative of the unsteady gas flow in two strokes, but hopefully, it gives a few pointers to what could help performance? I don't think even high-end CFD can fully model the chaotic events inside the engine. All good fun, though :) Cheers for watching Dave :)
Hi, I'm not that up on 4Ts but I know they do a lot of flow testing with them, but Dr Gordon Blair did use Time Area for 4 stoke development as I remember ? He did an article called: back to basics but I can't seem to fi d the link to it now?
I would claim that tesla turbine ice engine would be much more powerful at same size, and boosted. yep no pulsing issues, like in piston engines. its a full easy to make turbine, from stainless steel discs stacked in a can. yep, input air intake is tesla turbine pump boosted, and feeds air to the burner outside, kinda like carburetor but a burner, then feeds back to same axle output generator/power axle tesla turbine.
GreAt explantion of terminologys. My question is are we going to see something running. And where you @ with displacement and actual mph on the road not dyno. And hopefully this dont end up like a 6 yr journy like two stroke stuffing. Sadly he has gone backwards.
Hi Bryan, cheers and noted I need to get my finger out 😆 I had a real busy year last year with my dad being ill, and after he passed, I've struggled to get back into it, but I am getting there... Life's busy with checking on my mum and having two kids with hobbies/sports that take out most weekends... I am on it, though, and I want to get a base gearing set-up and the bike MOTed for a road shakedown to test jetting and ign timing under real world load conditions.
@@AutoBeta2T hey sorry to hear about your father. My father's 90 I'm here with him. Lost mom back in 2015 staid with her till the end now same story with dad. Finally we got out of the nhra prostock motorcycle racing. Hopefully not gonna build as many of them. Glad to see you tinkering on vid .
frits overmar is not a doctor 😂 he is only a journalist. he never worked at Aprilia, they didn't want to hire him. Jan Tiel gave him his notes when he retired
I just re read the article that Frits did on the leaning tower of pisa and it is incorrect as Frits didn't work for Aprillia but he did assist Jan with a lot of calculations. He a Jan decided to share their knowledge in the open forums once Jan retired.
you need to do a proper flow calibration on your printer sir. that looks like shit imo.. that would have been binned for recycling here. the overextrusion is heavy.. turn down the flowrate at least 10% for starters. then u need to check the procedure for your rig how to calibrate the flow. u might need to calculate esteps again. and the support material should snap off with one pull.. one should not need to machine away overextrusion like that. thats just.. reprint mate..
@@AutoBeta2T i suggest you do the cheaters route i call it. 1. make a square in the slicer and have it be hollow with one wall an no roof. 2. copy this "cup" and paste it four times so u have 5 of them. set each one to 0.1 incremental steps of flow in the slicer. 3. print and measure thickness of walls and divide by four for each of the 5 "cups" EDIT : label them with the text tool so they dont get mixed up after the print. 3 the one that you have the closest value to is ur set target for fine tuning :) 4.fine tuning is repeat process until satisfaction. some get thrown off by their zoffset squishing the first layer so much that the nozzle digs into the laid down material causing the filament to be moved to the sides in every layer. so when the next layer comes the nozzle does not have space to extrude in the correct place forcing the material to path of least resistance. this can look like overextrusion but its most likely both. this is creating this cumulative effect of distortions to finish and model. i suspect you get quite a lot of strings after travels and that your hotend get a bit dirty as well? its quite the easy job and will take you one or two goes to be happy enough to reply to this comment when its done and ur prints look pretty :) i do some 2stroke fun as well and i gotta say that it was clever to use the vac. kudos on the idea. im gonna steal that one :P back to porting the chainsaws puny 37.5cc !
As you know I've been a subscriber for a good while and never got round to saying thanks. Back in the day when there was no internet about the only option was guidelines in books followed by trial and error, anyhow I discovered a lot of things which worked but only had my imagination to figure out why/how but now I'm findin out for real the how/why thanks to you Dave.
Regards
Roy
Hi Roy, cheers for the kind words 😀
Same here, books and that was about it for me. I remember hearing about the Internet for the first time on John Cravens News Round when I was at school.
@@AutoBeta2T If you want I can send some vids for plotting expansion chamber templates old school style, basically a school geometry set, tape measure and a strip of cardboard (or similar). For most people wanting to make their own but don't have the software or like me just don't get on very well with computers. Yeah, it's primitive but how did Walter Kaden made the MZ ones back in the 50s or 60s?
It wouldn't be precise enough for the Aprillia gp team where they chase every half a horsepower but for someone who just wants an upgrade on their street bike it's close enough, after the cones etc are rolled and ground flat for welding the error is prolly plus or minus a millimeter
The vids were made for a freind but if you want them they're free to use, I just don't want the knowledge to die. You'll have to do a voiceover tho, my Geordie accent is pretty thick.
@@AutoBeta2T Computer printouts are more accurate obviously but if you're cutting the metal by.hand you're only ever gonna be plus or minus maybe half a millimeter anyhow and add to that some distortion if you're a bit too brutal when you're rolling it.
Good to see you're still diving deeper and deeper down the rabbit hole with this engine, these videos, like the early 2strokestuffing videos, will prove to be a treasured source of information in years to come.
Thank you for sharing your findings.
Cheers Darren 😃
Ive just come across your channel possibly by watching 2 stroke stuffing, but as a 16 yr old i had the autisa 93cc on my AR, i machined my head to lower the compression as i could never get the head to seal, I only got it to run right for short periods and never understood 2 strokes properly, but in 1998 YT didnt exist and i never had the funds for a tuner and so long as it got me to the training school i was happy ish, great content and many thanks as I yern for another try.
Nice and complicated =)
I usually actually go much easier way(deciding portsizes and timings), i just go by measurements and what available to acheive inside physical borders.
You got rules set by pistonring and so on and so on.
You also got rules set by blowdown duration.
(That '30deg' rule is a physical border)
Looking forward to next update, keep it up =)
But that part of MOTA simulating gas direction is interesting, i might need to upgrade =)
So the 2d sim isn't in Mota X?
@@AutoBeta2T no :(
I don´t think so, but i also have Mota 7 i just noticed, i might check that up some more =)
@@AutoBeta2T Man,, i can´t even start mota 7.
'run time error'... =(
@@AutoBeta2T I got it running,, changed the screenresolution.
New toys to play with =)
Damn, seen so few people going into the specifics like this. Way over my head but that why my engine ain't as powerful!
Great stuff.
Cheers Joshua
Really informative vid!
Cheers 😃
Excellent video Dave. It’s all a bit beyond my understanding - but I’m enjoying it anyway!
Cheers Duggers, it is a bit out there but something I needed to do. Some back to back cylinder head tests next so less theory and more practical 😃
Two stokes are part technology and part witchcraft, the technology points you in the right direction then after that, , , ,
If you want them I can send some vids I made for an Internet friend for drawing out expansion chambers old school, no computers, no printouts, just a school geometry set, tape measure and a strip of cardboard, It's prolly how Walter Kaden made the MZ ones in the 50s or 60s, not accurate enough to chase the last half of a horsepower but more than adequate for improving your street bike.
Assuming you can calculate the pipe length and cone tapers in the first place. You'll find that in the books Dave mentioned.
I also have a copy of Motorcycle Tuning 2 Stroke, signed by John Robinson. I bought it to see how 2 strokes work.
Cool 😎
It was the first two stroke book I owned. I must have been 16, I recon? Mine has been well read. I did think it could have gone into pipes a bit more but an excellent read.
@AutoBeta2T I agree about the exhaust section. I did find some calculations for 2 stroke exhausts. I can't remember where from ,it was over 30 years ago 😊
Very interesting! Would you say this measuring method you're using here could be utilised with car heads flow testing? What are the Hti Manometer measuring? Is there a way to measure the air speed?
Hi, I'm not sure if it could be used on 4 strokes? The software wouldn't, but I guess the pressure readings on the manometers could be used to show a change in flow.
The manometers are measuring pressure at the entry to the venturi and the delta between the entry and the throat. The software used this data along with anbient pressure and temperature to work out the flow time.area. So it should be calculating mass flow at each piston opening I believe?
Not sure exactly what your question is but you measure flow rate at different valve lift rates. Meaning on a flow bench. Build prostock nhra engines. But never tested with piston in different locations don't know how you would do that typically the flow bench is sucking from where the piston is located
Got to say this is one of the few channels I have come across where I can't find anything to pick at LOL.
Serious question though, what kind of gain would be achievable with say just a bit of moderate port work and then winding the compression up as far as possible along with some octane booster in the the fuel? (volumetric efficiency vs thermal efficiency)
Thanks.
Hi, cheers, and I'm pleased you are enjoying the videos.
The ports are already fairly maxed out from standard but still have some more to go, I think - that will come.
Next up is compression, but I plan to go lower first as more energy in the pipe in theory should help... but if that doesn't work, then I'll look to increase it higher.
I want to do the 100mph on pump fuel, which is 97 - 99 octane as per the original chalenge but until I can do some real world runs I won't know if I can get away with it.
@@AutoBeta2T Understood with the challenge. I have only picked this up somewhere in the middle so wasn't aware.
Back in the day I started out with a GP100, disk valve and all lol.
Shall watch with interest 👍
@@CATANOVA cool, enjoy 😁
YYYYEEEEEEAAAAAAAAAHHHHHHHHHHHHH!! Awesome!! 😁
Cheers Alexander - I hope you enjoyed?
@@AutoBeta2T Yes, i do and a 3d Printer is involved. Two of my favorite things!!!!
Cool - I think I need a 3d metal printer 😎
Hi, first of all, you're doing a really good work, keep it up!!! I'm also using Engmod2t, and I wanted to use it to create a tuned exhaust, but I'm a bit worried as the results in the program are good, whereas I don't know how it will perform in reality... Did you ever try to build an exhaust with its data? Also, did you ever check how your pipes perform in engmod compared to reality? Thanks for your time if you read all of this, and good luck for the growth of the channel! 😁
Hi Jacopo, cheers for the kind words 😀
Regarding exhausts, quite a few that were designed in EngMod2T. The results were always good, but note that I always started with a known pipe that had been dynoed and I have a curve for. I then worked in the sim to improve on it. I always seemed to have good results. The sim doesn't necessarily match the dyno readings especially if the runs are done on a inertia dyno (endmod is more like a load dyno) so the pipes may peak at different rpms compared to the dyno but if you measure accurately the generally an improvement in engmod will give a improvement in reality.
Cheers, Dave
@@AutoBeta2T thanks! 😁
new here.
the real, dry, airflow is with crankcase and crank in place.
the real, wet, airflow is with same, but well beyond this video series.
cliff
Hi Cliff, welcome to the channel 😀
Yep, as you say, what I am doing here is not representative of the unsteady gas flow in two strokes, but hopefully, it gives a few pointers to what could help performance?
I don't think even high-end CFD can fully model the chaotic events inside the engine.
All good fun, though :)
Cheers for watching
Dave :)
Haven't heard time area used with four strokes, but should be "same" flow vs cam
Hi, I'm not that up on 4Ts but I know they do a lot of flow testing with them, but Dr Gordon Blair did use Time Area for 4 stoke development as I remember ?
He did an article called: back to basics but I can't seem to fi d the link to it now?
@@AutoBeta2T not sure, it just made sense, I'm building a flowbench myself.
Cool - that will be really when you get it done.
@@AutoBeta2T yup annoying part is programming on my budget....
Is there some off the shelf flowbench software?
I think performance trends does one?
I would claim that tesla turbine ice engine would be much more powerful at same size, and boosted. yep no pulsing issues, like in piston engines. its a full easy to make turbine, from stainless steel discs stacked in a can. yep, input air intake is tesla turbine pump boosted, and feeds air to the burner outside, kinda like carburetor but a burner, then feeds back to same axle output generator/power axle tesla turbine.
Sounds like a cool engine 😎
@@AutoBeta2T yeah hot and cold, yes and no, lol
GreAt explantion of terminologys. My question is are we going to see something running. And where you @ with displacement and actual mph on the road not dyno. And hopefully this dont end up like a 6 yr journy like two stroke stuffing. Sadly he has gone backwards.
Hi Bryan, cheers and noted I need to get my finger out 😆
I had a real busy year last year with my dad being ill, and after he passed, I've struggled to get back into it, but I am getting there...
Life's busy with checking on my mum and having two kids with hobbies/sports that take out most weekends...
I am on it, though, and I want to get a base gearing set-up and the bike MOTed for a road shakedown to test jetting and ign timing under real world load conditions.
@@AutoBeta2T hey sorry to hear about your father. My father's 90 I'm here with him. Lost mom back in 2015 staid with her till the end now same story with dad. Finally we got out of the nhra prostock motorcycle racing. Hopefully not gonna build as many of them. Glad to see you tinkering on vid .
@2strokecarbtuningportingin187 cheers buddy 😊
frits overmar is not a doctor 😂 he is only a journalist.
he never worked at Aprilia, they didn't want to hire him.
Jan Tiel gave him his notes when he retired
I just re read the article that Frits did on the leaning tower of pisa and it is incorrect as Frits didn't work for Aprillia but he did assist Jan with a lot of calculations. He a Jan decided to share their knowledge in the open forums once Jan retired.
FOS > Full Of S**t
Cool it's autobeta ! Broooo 👀🙋
Thanks ✌
you need to do a proper flow calibration on your printer sir. that looks like shit imo.. that would have been binned for recycling here. the overextrusion is heavy.. turn down the flowrate at least 10% for starters.
then u need to check the procedure for your rig how to calibrate the flow. u might need to calculate esteps again. and the support material should snap off with one pull.. one should not need to machine away overextrusion like that. thats just.. reprint mate..
Cheers for the tips. I've had that printer for some time now but I've never delved into setting it up properly. Something to do for next time.
@@AutoBeta2T i suggest you do the cheaters route i call it.
1. make a square in the slicer and have it be hollow with one wall an no roof.
2. copy this "cup" and paste it four times so u have 5 of them. set each one to 0.1 incremental steps of flow in the slicer.
3. print and measure thickness of walls and divide by four for each of the 5 "cups" EDIT : label them with the text tool so they dont get mixed up after the print.
3 the one that you have the closest value to is ur set target for fine tuning :)
4.fine tuning is repeat process until satisfaction.
some get thrown off by their zoffset squishing the first layer so much that the nozzle digs into the laid down material causing the filament to be moved to the sides in every layer. so when the next layer comes the nozzle does not have space to extrude in the correct place forcing the material to path of least resistance. this can look like overextrusion but its most likely both.
this is creating this cumulative effect of distortions to finish and model. i suspect you get quite a lot of strings after travels and that your hotend get a bit dirty as well?
its quite the easy job and will take you one or two goes to be happy enough to reply to this comment when its done and ur prints look pretty :) i do some 2stroke fun as well and i gotta say that it was clever to use the vac.
kudos on the idea. im gonna steal that one :P
back to porting the chainsaws puny 37.5cc !