Thank you for the shout out! 👍👍I think you can use cone layout for free for 3 weeks or something, and I think it even works after that but there will be a longer delay the longer it goes. It's worth the money though imo, a real time saver. I'm not affiliated btw ;)
There shouldn't be any power loss if it is done neatly as the function of the pipe is by changes in pipe area (diameter) down the pipe so changes in direction are not an issue.
Would you be able to design an expansion chamber for a 2 cylinder 250cc engine where the exhaust ports are Y piped together into one expansion chamber?
when I enter my cone dimensions my D and C value are so high that they go off the page, and i also dont even own a protractor that goes past 300mm. Perhaps ive made an error?
The cone layout dimensions for most pipes are not likely to fit on a A4 page. You need to draw them on a larger paper to trace them on to sheet metal. You will need a compass with an extender on it to trace a cone layout. The one I've done in the video is just for demonstration purposes.
Hi, i have an old tomos ctx, and i would like to copy the same exhaust, and build under same meshurments. Can you tell me some tips before i destroy the old one haha
where do i find all information to put in the program?I have piaggio zip 71cc 48mm bore from top performance and its AC. I want to make a custom exhaust as school project.Can someone help me please
Do you man all the parameters to put in to the Pipe software ? If you hold the mouse over each on the entry boxes in the software a popup help gives you more information on each box.
Not too much to ask, it just comes down to how much time and money you have, if you have the time and equipment you could make a set yourself and if you have the money you might be able to buy a set of factory expansion chambers to suit if there is ones made to suit your engine.
@@AuMechanic Yeah, I thought it would have the advantage of not having kinks that could disrupt airflow. I've seen 500cc Grand Prix motorcycle pics, some of them have "cone segments"exhaust, and some have hydro formed exhausts.
@@AuMechanic please I need help I already have the cone layout program but the format is different. how I set it up so that it comes out to me like you thanks
Not from the program and in most cases the flat cone size is larger then A4 used in most standard printers. If you have a printer that can do larger sizes you could use the size values given in the program in a basic CAD type program to draw and then print the cones, but chances are you could do it faster using the method explained in the video.
What is the formula for including the wall thickness in the cone sizes? I need to know the diameters ( including the wall thickness) for a other software. If I ad 2 times the wall thickness to de diameter of the cone and print it out than the numbers don’t ad up with the numbers in your software.
Double the sheet thickness is simply added to the diameters of the cone ends (cut off tip being a "frustrum") which ensures the inside diameter of the cone is per the formula. Keep in mind all pipe dimensions are based on the inside of the pipe as they are all related to the port diameter. Whatever the outside dimensions are is only a construct of the sheet thickness used.
@@AuMechanic Thanks for the answer but why aren't these the same numbers than? base=42mm tip=22mm length=30mm thickness metarial=0mm A=111,29 B=58.29 C=34.79 D=66.41 base=40mm tip=20mm length=30mm thickness metarial=1mm A=109,29 B=56.16 C=31.62 D=63.25. These are the numbers out of your software
@@juliank3397 Because the centre length of 2 cones is not the same once you roll the cones out of different thickness material, it then has the angle 90 degree to the angle of the cone at each ends across the material thickness. To make it the same you grind the cone ends level after it is rolled so that they mate flush with one another to weld, But that is a detail of fabrication where you surface each cone on a linishing belt.
@@2downshifter No you would just design each one to suit each separate port. So the diameters of each pipe would be based on the area of each single port. The tune lengths would be the same if the timing of both ports is the same.
@@2downshifter Last I recall one of these had had 2 separate exhausts and if that is the case then build 2 exhaust. Alternatively if the bike has a 2 into one header then I would use that and build one pipe and for that you would treat the 2 ports as if it was 1 bridged port and use total area of both ports in the 1 pipe design.
How far off is B dimension ?Any discrepancy on the A or C dimension will result in B not being dead on but it can be hard to get it spot. Also all dimension are rounded of to nearest decimal So long as you make measurements as close as possible using a vernier caliper an tech drawing compass that will be fine.
Sir I am from India where 2 stroke engines are illegal due to pollution. But the bunch full of people who has previously owned 2 stroke bikes are maintaining them like jewels. Can you kindly give me the dimensions for Yamaha rx 135 4 speed. I do not have enough data to put into the software, but really want to construct a expansion chamber. Kindly help .
So far I have found on Google the Indian RX135 is 12 BHP power at 7,500 RPM, 58 mm bore and 50 mm stroke so use the input calculator in the software (tools menu) to convert that to kW and then you can input that and bore and stroke in to get BMEP and from that an average Exhaust temperature. I have done that already and 12 BHP power = 8.948 kW power, so using that 8.948 kW and 58 Bore and 50 Stroke and 7,500 RPM = 5.42 Bar BMEP which is estimated Exhaust gas temp of 350 C So use 350 C as Exhaust temp in the pipe calculator section. The next is maximum RPM value to insert, just insert the value of what the red line RPM is on your tachometer on the bike. The other dimensions of port diameter, port length, port flange diameter and port timing you will need to measure on the engine, if you look through more of my videos on my channel page I explain how to measure port timing on one video and the other three port dimensions in another video.
@@AuMechanic I shared your channel to our small local 2stroke's fb group where I am the admin . It has around 9k active members. Hope they will be benefited by your lectures and practicals.
hi man , it would be nice if we could just print out the layout on to paper , just cut it out en done :) just saying n would make my life easy-er-der =-D
Thank you for posting this series, I really enjoy learning more about two strokes from someone who doesn’t go on about the bullshit theories that sorta technically kinda work, any word on when the whole series will be finished and posted?
I wish that was true, I had a business in the 1980's doing engine mods, race tuning and building expansion chambers and I also road raced 2 strokes, but building custom chambers proved to be not profitable, most opting for cheaper off the shelf "road and track" pipes, back then I did it for the passion and I suspect for others who make them it is probably the same. There is a reward in seeing someone come back in after a race saying they just got the best lap times they have had so far due to the new pipes you just built, even if it doesn't pay so well.
Your understanding of the 2 stroke is amazing, these vids you put out are quality! ! Thanks for sharing with us
Thank's for the comment
Thank you for the shout out! 👍👍I think you can use cone layout for free for 3 weeks or something, and I think it even works after that but there will be a longer delay the longer it goes. It's worth the money though imo, a real time saver. I'm not affiliated btw ;)
How do you say your name?
Thank you so much, Jacques
nice job... i made exhaust too. and make my owm pattern
how much power is effected by twisting pipe to fit bike in compare with strait expansion chamber?
There shouldn't be any power loss if it is done neatly as the function of the pipe is by changes in pipe area (diameter) down the pipe so changes in direction are not an issue.
Thank You
Would you be able to design an expansion chamber for a 2 cylinder 250cc engine where the exhaust ports are Y piped together into one expansion chamber?
when I enter my cone dimensions my D and C value are so high that they go off the page, and i also dont even own a protractor that goes past 300mm. Perhaps ive made an error?
The cone layout dimensions for most pipes are not likely to fit on a A4 page.
You need to draw them on a larger paper to trace them on to sheet metal.
You will need a compass with an extender on it to trace a cone layout.
The one I've done in the video is just for demonstration purposes.
Hi, i have an old tomos ctx, and i would like to copy the same exhaust, and build under same meshurments. Can you tell me some tips before i destroy the old one haha
where do i find all information to put in the program?I have piaggio zip 71cc 48mm bore from top performance and its AC.
I want to make a custom exhaust as school project.Can someone help me please
Do you man all the parameters to put in to the Pipe software ?
If you hold the mouse over each on the entry boxes in the software a popup help gives you more information on each box.
I just need a set of insane custom x7 pipes that sound unreal .... is that too much to ask
Not too much to ask, it just comes down to how much time and money you have, if you have the time and equipment you could make a set yourself and if you have the money you might be able to buy a set of factory expansion chambers to suit if there is ones made to suit your engine.
Can you show how to use cone layout with angels so you can make a bent header
Try this one www.kzell.com/calculators/
I usually just cut and twist the piece 180 degree to get the bends I want.
What do you think about hydro formed expansion chambers? Seems easier to fabricate, there's only the seam weld,
Its the best way to make a clean pipe, but only if done properly.
@@AuMechanic Yeah, I thought it would have the advantage of not having kinks that could disrupt airflow. I've seen 500cc Grand Prix motorcycle pics, some of them have "cone segments"exhaust, and some have hydro formed exhausts.
could you please tell me which calculator handles
There are links in the description section below the video.
@@AuMechanic please I need help I already have the cone layout program but the format is different. how I set it up so that it comes out to me like you thanks
That program is only for cases where you need the have a bend at the cone, if you use it you can take the cone values from my program to use in it.
What is a good thickness for sheet metal or gauge?
Depends on the material you use.
For steel about 1.5mm
Can you print it on paper?
Not from the program and in most cases the flat cone size is larger then A4 used in most standard printers.
If you have a printer that can do larger sizes you could use the size values given in the program in a basic CAD type program to draw and then print the cones, but chances are you could do it faster using the method explained in the video.
done sub
What is the formula for including the wall thickness in the cone sizes? I need to know the diameters ( including the wall thickness) for a other software. If I ad 2 times the wall thickness to de diameter of the cone and print it out than the numbers don’t ad up with the numbers in your software.
Double the sheet thickness is simply added to the diameters of the cone ends (cut off tip being a "frustrum") which ensures the inside diameter of the cone is per the formula. Keep in mind all pipe dimensions are based on the inside of the pipe as they are all related to the port diameter.
Whatever the outside dimensions are is only a construct of the sheet thickness used.
@@AuMechanic Thanks for the answer but why aren't these the same numbers than?
base=42mm tip=22mm length=30mm thickness metarial=0mm A=111,29 B=58.29 C=34.79 D=66.41
base=40mm tip=20mm length=30mm thickness metarial=1mm A=109,29 B=56.16 C=31.62 D=63.25.
These are the numbers out of your software
@@juliank3397 Because the centre length of 2 cones is not the same once you roll the cones out of different thickness material, it then has the angle 90 degree to the angle of the cone at each ends across the material thickness. To make it the same you grind the cone ends level after it is rolled so that they mate flush with one another to weld, But that is a detail of fabrication where you surface each cone on a linishing belt.
@@AuMechanic thanks for the clarification
I'm trying to make a radius header not straight what is the trick to calculating the angle vs radius?
See the link to angled cone calculator in the description area below the video.
@@AuMechanic i haven't figured out how to do it in conelayout if it is possible... I'm using the version on the site now.
My bike is a single cylinder & has two exaust ports, should I design two seperate chambers or is there any other logic for this scenario? (Jawa 250)
If you mean it has two outlet flanges of the exhaust port in a single cylinder then yes they usually do build 2 pipes.
@@AuMechanic thanks, should I need to build two pipes with same calculations, or will there be a different method of calculating the dimensions?
@@2downshifter No you would just design each one to suit each separate port.
So the diameters of each pipe would be based on the area of each single port.
The tune lengths would be the same if the timing of both ports is the same.
@@2downshifter Last I recall one of these had had 2 separate exhausts and if that is the case then build 2 exhaust.
Alternatively if the bike has a 2 into one header then I would use that and build one pipe and for that you would treat the 2 ports as if it was 1 bridged port and use total area of both ports in the 1 pipe design.
@@AuMechanic got it, il build 2 seperate pipes, as it looks good, so il consider 2 areas & calculate the remaining dimensions.
What apps your used in compumter to computed??
See the description section below the video for links to software.
My B dimension is never on point.What's the problem?
How far off is B dimension ?Any discrepancy on the A or C dimension will result in B not being dead on but it can be hard to get it spot.
Also all dimension are rounded of to nearest decimal
So long as you make measurements as close as possible using a vernier caliper an tech drawing compass that will be fine.
@@AuMechanic its like 5 mm off, and all the other dimensions are spot on
@@boostedhub7762
Let me know what the base and tip diameters are and sheet thickness and I'll have a look at it.
Sir I am from India where 2 stroke engines are illegal due to pollution. But the bunch full of people who has previously owned 2 stroke bikes are maintaining them like jewels. Can you kindly give me the dimensions for Yamaha rx 135 4 speed. I do not have enough data to put into the software, but really want to construct a expansion chamber. Kindly help .
So far I have found on Google the Indian RX135 is 12 BHP power at 7,500 RPM, 58 mm bore and 50 mm stroke so use the input calculator in the software (tools menu) to convert that to kW and then you can input that and bore and stroke in to get BMEP and from that an average Exhaust temperature.
I have done that already and 12 BHP power = 8.948 kW power, so using that 8.948 kW and 58 Bore and 50 Stroke and 7,500 RPM = 5.42 Bar BMEP which is estimated Exhaust gas temp of 350 C
So use 350 C as Exhaust temp in the pipe calculator section.
The next is maximum RPM value to insert, just insert the value of what the red line RPM is on your tachometer on the bike.
The other dimensions of port diameter, port length, port flange diameter and port timing you will need to measure on the engine, if you look through more of my videos on my channel page I explain how to measure port timing on one video and the other three port dimensions in another video.
@@AuMechanic sure sir, I will try the same from my end. Thanks for the quick reply. You are truly an inspiration for many.
@@ronosys
Let me know if you have any questions
@@AuMechanic sure sir, I will let you know the update.
@@AuMechanic I shared your channel to our small local 2stroke's fb group where I am the admin . It has around 9k active members. Hope they will be benefited by your lectures and practicals.
hi man , it would be nice if we could just print out the layout on to paper , just cut it out en done :)
just saying n would make my life easy-er-der =-D
I can’t find the software can someone link it?
I just added a link in the description section above to the pipe software.
Thank you for posting this series, I really enjoy learning more about two strokes from someone who doesn’t go on about the bullshit theories that sorta technically kinda work, any word on when the whole series will be finished and posted?
Isn't it millimeter?
Do you mean Metre v Meter ?
You should open a pipe company you would be rich
I wish that was true, I had a business in the 1980's doing engine mods, race tuning and building expansion chambers and I also road raced 2 strokes, but building custom chambers proved to be not profitable, most opting for cheaper off the shelf "road and track" pipes, back then I did it for the passion and I suspect for others who make them it is probably the same. There is a reward in seeing someone come back in after a race saying they just got the best lap times they have had so far due to the new pipes you just built, even if it doesn't pay so well.