Andy you are my motorcycle professor ... just want to say thank you for all the knowledge you share ..I recommend you to all my bike buddies... But sincerely thank you
Hands down the best explanation of exhaust I’ve ever heard. Thank you. Just found your channel today and subscribed. Maybe sometime you could give an explanation of the need to put a Dynojet Power Commander on when changing the exhaust? And how it works.
Thank you so much for this video. I definitely have a better understanding of how the exhaust system works. You have provided me with the knowledge to make a much better decision on the exhaust systems I will purchase and install on my future motorcycle projects. Thanks again from Illinois in the USA.
Brilliant bit of knowledge! I should send a picture of the custom exhaust on my Monster 1100 and let you tell me everything I did wrong with it! Ha Ha Ha! In all seriousness I found this extremely enlightening.
Thank you some much for the video! I have a question. If I install a full system on a carbed xx1100 do I need to do some other adjustment for best performance? Thank you!
Hi Andy, thanks for that. I have a Triumph Daytona T595 with a Scorpion silencer, which I fitted a dbkiller to. A few days ago I bought and fitted a k&n filter but was running with less power and kept stalling at round abouts, traffic lights etc... I took the dbkiller out which has cured the stalling but now it feels under powered and of course louder. I have a folder on my computer with every tune for the ecu, from Tune ECU but could really use some info on what's happening so I can choose the right tune for the ECU. Ideally I would like the dbkiller back in, I like my bikes a wee bit quieter, I don't really, I actually love the roar of the triple engine but the police don't and neither do my neighbours at 6am. When I got the dbkiller, with the oem air filter, the bike felt restricted so I drilled 4 holes in the dbkiller, it worked and the bike has run great since I put the K&N in. I was going to make more holes. Am I on the right road please. Noise cancellation is important to me but stock silencers aren't, I have one and they're dreadful. Thanks for any help, Jim.
James McCreadie g’day mate. I used to own a ‘05 955i Daytona so I understand where you’re coming from, great noise from the triples. I had a Megacycle exhaust with standard filter and it ran and sounded great. Drilling more holes would be my approach but the issue is that once you drill too many it is hard to un-drill them. Thanks for watching, Andy
Thanks Andy, I'll do that. I really enjoyed watching the basket case vids, there's a big difference in watching and learning from a time served engineer than an enthusiast, like the exhaust bracket you made, excellent and not to mention the lengths you went to solve all that bikes issues. I can't tell you how much I enjoyed that build.. hoping you get another project because it was a pleasure.
Hi Andy. Just to follow up about the Daytona. I drilled 4 equal holes opposite the existing ones and cut an inch off the dbkiller . Sorted. Running fab.
hey Buck very informative I have reverse megaphone pipe on my xr650r I did research it said they were the best ? or is that just a sales pitch ? I don't know I feel just two independent pipes with mufflers would be hard to beat ?
i have a er6n 2014 i change the exhaust for a blackwidow short link pipe would my engine be smoother with a long normal pipe thats bolts to the passenger foot rest
Sir, Your Video was great in the terms of knowledge delivery, but i have a technical question, How do we understand that what kind of different different sounds can be derived from one particular engine using different silencers and mufflers?
Not really, it’s a complex issue and depends on the engine size and target RPMs, among other considerations. Maybe a read of this will help www.centuryperformance.com/exhaust-header-tube-sizing-and-length.html and I would advise that you do some targeted research specific to your bike. See if you can contact a manufacturer and talk to them, they would have done the r&d already. Or even someone who sells something similar and measure the length of the primary tubes.
Hey there, I hava a doubt,may be u can call it a Confusion,i own a RE Continental Gt650,i have installed a RedRooster Perfomance-Stellar Exhaust(Slipons),so i would like to know If Removing db killer and,will it causee a back pressure to engine,which might lead to overheating of exhaust valve or enginee temprature and the engine life ,is it true,Can anyone explain this Scenes?? Thanks In Advance:)
I can't answer that mate, I don't know what jets are factory and I have never played with a KZ1000. Have you tried the forums? I would recommend reading the spark plugs to check the current condition, i.e. are you actually running lean?
Ok thanks for getting back to me..yur CZcams vids are great..now here's the story about this bike..bought it off neighbor for two hundred American dollars..the bike sat in storage for a year or two and upon me buying it the number one carb was siezed up..took the carbs off had a garage clean em up..and a couple pilot jets and air fuel screws were broke and needed drilled out..got the carbs back put em on and the bike fired right up..upon running temp the bike started popping and deceleration backfire..then I looked at the carbs and gas is coming out the bottom of carbs not float drain..it turns out that the mechanic had to scrounge up some old pilot jets and air screws..took carbs off again and the main jet is still a 107.5 with a pilot of 15..now my service manual calls for a 105 main and a 15 pilot stock before air cones and 4n1exhaust..now I read that with the new volume of air due to the cones I will have tu go up two jet sizes..I ordered new jets and gaskets and will be picking em up tomorrow..unfortunately it's 6degrees out..way cold..I haven't had a chance to Wrk on the bike..as soon as it gets above freezing I will put it all together..I hope this helps.the jets I ordered are a 107.5main and a 17.5 pilot..I don't know of any kz forums..yur help would greatly be appreciated..thx
Hey Andy, at 12:12 you say that the closer the junction to the cylinder head, the lower in the RPM range the exhaust scavenging will take effect. I'm a bit confused here: if the distance the exhaust pulse has to travel is lesser, doesn't it mean that it does so faster and hence is effective at higher RPM where the other cylinder will fire sooner? If the RPM is low, it means that the firing time between the two cylinders is greater and so the exhaust pulse from one has more time (and therefore requires more distance) to reach the other. Am I missing something here?
Excuse me, may i ask you a few questions? what will happen if i took Exhaust pipe off but leave catalytic converter as it be. is it bad ? because if i put slip on exhaust with catalytic converter on a sound didn't change and if i replace it with some link pipe to header it too loud for me. it's Yamaha MT-10 it (would be great if you can give me some advices.)
Hi mate, it shouldn't be an issue. Most of the work has been done before the muffler. The catalytic converter will kill decibels so I'm not surprised that you are disappointed with a slip on.
The stock exhaust on the XS1100 is about the best you can get-which makes replacing them a royal PIA. The only viable replacement here in the States is the Mac 4 into 1 but I'm not giving up my center stand. My headers are okay, it's my mufflers that look like something out of Mad Max. A PO drilled out 4 holes in the back of each muffler to make it louder-could that have possibly affected flow? I plugged them with jack bolts to get the stock mufflers back to original form but now I'm tempted to remove them because they look like crap. Come to think of it my whole bike looks fairly rough. Good mechanically-but it'd be nice to someday do a little cosmetics.
+James Robert I've seen photos of your bike on Facebook, I think. I agree with you about the XS11 pipes, they provide a good broad power spread. Got to love PO's, thanks for watching, Andy
'PO's' either means 'previous owner' or 'pissed off'. Probably both in most cases. I'd like to find some mufflers that match the pipes and try to weld some mounting brackets on. Not sure if the crossover pipe would be possible to do or whether it would help get the same performance spread as the stock set.
hi. I just decided to pull out my dad's old yamaha xs eleven special because he died when I was 5 years old and sat in one of our barns for over 25 years. I'd like to fix it and get running and make it street legal, then slowly make it look new again. any advice? no one around me will even touch it or give me advice on it. not even the dealers.
+truenorge10 G'day mate, thanks for tuning in. My advice would be to join the forums, US, Australia and U.K. Also their Facebook pages. There is a wealth of knowledge and a passion to support anyone wanting to get these great classics back on the road. Your motivation is commendable and your dad would be proud of you. If you have any specific questions don't be afraid to ask, if I can't answer them I should be able to point you in the right direction. Also look us up on Facebook, you can message me from the page. Andy
G'day mate. I purchased it 2nd hand along with a box of other bits and pieces from an on-line auction site. the muffler was purchased from Motorcycle Exhaust Professionals in Queensland.
removing back pressure is only good for engines that are ALWAYS running in the high rev ranges, removing the back pressure WILL cause the engine to loose a lot of mid range torque and can cause miss firing in some cases. if you dont believe me then do some dyno testing before and after you remove the back pressure
You didnt mention anything about TAPERED exhaust pipes and TAPERED baffles. Hot exhaust gas wants to expand and will travel much faster thru a tapered pipe/baffle than a straight one. As the exhaust pulse (high pressure/low speed) enters the pipe, it wants to move toward the larger less restrictive area of the taper, which causes a low pressure area behind that pulse, which helps the following interval high pressure pulse to enter the pipe, thus scavenging happens helping the engine to BREATHE. That's the reason that most all exhaust muffler systems are TAPERED, such as the one on your bike. There not just for SOUND.
correction : "back pressure is bad, always... unless you drive at exactly the right number of RPMs according to the timing of your back pressure, always"
You don't talk like an automotive engineer. You might want to check with one. Back pressure is used by exhaust designers to help the valves do their job more efficiently
andy if it were me I would take the Tasmanian outline use the Tasmanian cartoon character if you could without copyright infringement or something close to it on a motorcycle with your name that would definitely Define your artwork or use you your face on the Tasmanian body the world win and a motorcycle that would be awesome
Hi Paul, yeah that would be really cool. I used a pick of a Taz on a bike as a thumbnail when I posted about a ride I did with my daughter a while back. Not too sure how I'd go fighting Warner Brothers though. Thanks mate.
"Fresh air is drawn into the cylinder by a pressure differential, a vacuum left in place of the withdrawn piston. Just dont say it was SUCKED in....mother nature will get ornery."
I don't know, if the engine doesn't suck in air, you wouldn't mind revving the engine to about five grand and sticking your noodle in the carb would you? perhaps another video, behind a curtin please, just leave your face above the screen so we can catch your expression!
You have some exhaust info down, some you are off, you spend too much time trying to over complicate your explanations. Also vacuum = suction, venturi affect takes place because the engine is pulling air through the carb. place your hand over any carb and you will feel the suction. I get what you were attempting to explain but again you're off the mark. Another thing to mention is that like others have stated back pressure can have great affect on low/mid range torque something very important for towing etc back pressure can also reduce fuel consumption. I would advice you get back to basics and learn a wider variety of systems before you start trying to "teach" because at this point you are only spreading an off base opinion. Cheers
You are very poor at explaining things. I lose confidence when you say the first stroke is not suction, of course it is. Suction is created with differential pressure and tthe gas is drawn from high to low pressure. When you suck through a straw you create a negative pressure in your mouth. .....Then you seem to want to put your own Ausi slant on every else and I am sorry, it is a muddle and teaches me nothing.
+Allan Byrne hi Allan, I'm sorry if I didn't explain myself very well. The point I was trying to make is that an engine doesn't work like a vacuum pump. Air isn't sucked into the cylinder but actually flows in at whatever atmospheric pressure is present at that elevation. That's why elevation has an impact, lower pressure = less air and therefore less oxygen available for combustion. Andy
I just watched this back and I am struggling to see what your point is? I said twice that air is introduced by pressure differential. I also can't find the "Aussie slant" you're referring to, it is just basic international engineering principles. I think I detect a hint of xenophobia and I am now doubting that it is me that is creating a cognitive block.
The atmospheric pressure has no bearing on the principle of "suction", that of a medium flowing from a high to low pressure area. To be exact, at a higher altitude the air is just less dense, as there are fewer oxygen molecules present, making breathing difficult. I am trying to design a baffle for my old Honda NV400 and getting information is both difficult and contradictory. I am beginning to think there are as many opinions as there are bikers and that it will be a process of trial and error for me. My one hope is that I can find one, take a look and copy it, but the bike is rare, although the early VT500 is similar.
+Allan Byrne I have been trying to explain that what I am saying is exactly what you are saying , in terms of differential pressure. Copying what others have done is always a good strategy, assuming they got it right. Andy
Sorry mate, I thought you were having a go at me. As I said, delicate balance between flow and velocity, I think that is where the "back pressure" misconception comes into it. You require enough restriction to promote velocity but want to avoid back pressure, it is an engineering fact. It's not that everyone is wrong, it is just that a large number who don't understand fluid dynamics and the principles of flow and pressure have difficulty understanding why you need any restriction at all. Look into Bernoulli's work and study his principles.
If you don't believe me, just ask this scientition czcams.com/video/3zfLnOnnW2A/video.html
Andy you are my motorcycle professor ... just want to say thank you for all the knowledge you share ..I recommend you to all my bike buddies... But sincerely thank you
+Vincent Ramella that's bloody kind of you Vincent, thank you. Andy
Hands down the best explanation of exhaust I’ve ever heard. Thank you.
Just found your channel today and subscribed.
Maybe sometime you could give an explanation of the need to put a Dynojet Power Commander on when changing the exhaust? And how it works.
Thank you so much for this video. I definitely have a better understanding of how the exhaust system works. You have provided me with the knowledge to make a much better decision on the exhaust systems I will purchase and install on my future motorcycle projects. Thanks again from Illinois in the USA.
Cheers Mike
Best explanation I've ever heard/seen; thanks!
Lovely explanation on how exhaust’s work, love your no bullshit content.
cheers mucka, your way of explaining things is enjoyable and easy to take in so I learned something :-)
Very well done! Thank you. All the best! The Crew
Brilliant bit of knowledge! I should send a picture of the custom exhaust on my Monster 1100 and let you tell me everything I did wrong with it! Ha Ha Ha! In all seriousness I found this extremely enlightening.
Back pressure is needed at low end for torque
It
Thank You for sharing your thoughts. This is great stuff!
very descent explentation, it will help making a custom muffler for my cb400f project. thx
Andy great job boy you like the tough ones lol well done mate!
Thanks Andy , good stuff
Excellent Content Sir.
thank you
Great explanation 👍
Thank you some much for the video! I have a question. If I install a full system on a carbed xx1100 do I need to do some other adjustment for best performance? Thank you!
Amazing, thank you
Thank you .... so good ..... regards Fred
Hi Andy, thanks for that.
I have a Triumph Daytona T595 with a Scorpion silencer, which I fitted a dbkiller to. A few days ago I bought and fitted a k&n filter but was running with less power and kept stalling at round abouts, traffic lights etc... I took the dbkiller out which has cured the stalling but now it feels under powered and of course louder. I have a folder on my computer with every tune for the ecu, from Tune ECU but could really use some info on what's happening so I can choose the right tune for the ECU. Ideally I would like the dbkiller back in, I like my bikes a wee bit quieter, I don't really, I actually love the roar of the triple engine but the police don't and neither do my neighbours at 6am.
When I got the dbkiller, with the oem air filter, the bike felt restricted so I drilled 4 holes in the dbkiller, it worked and the bike has run great since I put the K&N in. I was going to make more holes. Am I on the right road please.
Noise cancellation is important to me but stock silencers aren't, I have one and they're dreadful.
Thanks for any help, Jim.
James McCreadie g’day mate. I used to own a ‘05 955i Daytona so I understand where you’re coming from, great noise from the triples. I had a Megacycle exhaust with standard filter and it ran and sounded great. Drilling more holes would be my approach but the issue is that once you drill too many it is hard to un-drill them. Thanks for watching, Andy
Thanks Andy, I'll do that. I really enjoyed watching the basket case vids, there's a big difference in watching and learning from a time served engineer than an enthusiast, like the exhaust bracket you made, excellent and not to mention the lengths you went to solve all that bikes issues. I can't tell you how much I enjoyed that build.. hoping you get another project because it was a pleasure.
Hi Andy. Just to follow up about the Daytona. I drilled 4 equal holes opposite the existing ones and cut an inch off the dbkiller . Sorted. Running fab.
Andy I have a question if you add a aftermarket exhaust system and now there’s more free flow so do you add more fuel or do you lean it out
Awesome information 👏 my question is would rifling have a similar effect so would it create that suction like a turbo under its own power?
hey Buck very informative I have reverse megaphone pipe on my xr650r I did research it said they were the best ? or is that just a sales pitch ? I don't know I feel just two independent pipes with mufflers would be hard to beat ?
i have a er6n 2014 i change the exhaust for a blackwidow short link pipe would my engine be smoother with a long normal pipe thats bolts to the passenger foot rest
Sir, Your Video was great in the terms of knowledge delivery, but i have a technical question,
How do we understand that what kind of different different sounds can be derived from one particular engine using different silencers and mufflers?
Class act👍
Wery nice talk
do you know a website or equation on explaining where to place the collector? I'm building a 2 into 1 exhaust and that would help alot. thanks.
Not really, it’s a complex issue and depends on the engine size and target RPMs, among other considerations. Maybe a read of this will help www.centuryperformance.com/exhaust-header-tube-sizing-and-length.html and I would advise that you do some targeted research specific to your bike. See if you can contact a manufacturer and talk to them, they would have done the r&d already. Or even someone who sells something similar and measure the length of the primary tubes.
Hey there,
I hava a doubt,may be u can call it a Confusion,i own a RE Continental Gt650,i have installed a RedRooster Perfomance-Stellar Exhaust(Slipons),so i would like to know If Removing db killer and,will it causee a back pressure to engine,which might lead to overheating of exhaust valve or enginee temprature and the engine life ,is it true,Can anyone explain this Scenes??
Thanks In Advance:)
I have a 77kz1000ltd with cone filters and 4into1exhaust my jets are set up as 107.5main with a 15pilot..is this correct for the cones and exhaust?
I can't answer that mate, I don't know what jets are factory and I have never played with a KZ1000. Have you tried the forums? I would recommend reading the spark plugs to check the current condition, i.e. are you actually running lean?
Ok thanks for getting back to me..yur CZcams vids are great..now here's the story about this bike..bought it off neighbor for two hundred American dollars..the bike sat in storage for a year or two and upon me buying it the number one carb was siezed up..took the carbs off had a garage clean em up..and a couple pilot jets and air fuel screws were broke and needed drilled out..got the carbs back put em on and the bike fired right up..upon running temp the bike started popping and deceleration backfire..then I looked at the carbs and gas is coming out the bottom of carbs not float drain..it turns out that the mechanic had to scrounge up some old pilot jets and air screws..took carbs off again and the main jet is still a 107.5 with a pilot of 15..now my service manual calls for a 105 main and a 15 pilot stock before air cones and 4n1exhaust..now I read that with the new volume of air due to the cones I will have tu go up two jet sizes..I ordered new jets and gaskets and will be picking em up tomorrow..unfortunately it's 6degrees out..way cold..I haven't had a chance to Wrk on the bike..as soon as it gets above freezing I will put it all together..I hope this helps.the jets I ordered are a 107.5main and a 17.5 pilot..I don't know of any kz forums..yur help would greatly be appreciated..thx
Damn, I was hoping you would get into eXup valves.
Hey Andy, at 12:12 you say that the closer the junction to the cylinder head, the lower in the RPM range the exhaust scavenging will take effect. I'm a bit confused here: if the distance the exhaust pulse has to travel is lesser, doesn't it mean that it does so faster and hence is effective at higher RPM where the other cylinder will fire sooner? If the RPM is low, it means that the firing time between the two cylinders is greater and so the exhaust pulse from one has more time (and therefore requires more distance) to reach the other. Am I missing something here?
I was thinking the same thing. Did you ever get an explanation on that?
I’m considering the M4 muffler for my ZRX1200. Is it “streetable” on your 1100?
Define "steetable" Murray. Is it loud? Of course it is. Is it louder or more obnoxious than a lot of V-twin shot gun set-ups? No.
Yeah, sorry Andy, that was ambiguous, wasn’t it!!
One further query........baffle out versus baffle in. Much difference??
You're assuming I've ever run it with the baffle in lol. In all seriousness mate, I wouldn't know. I've never tried.
Andy's Motorcycle Obsessions Hahaha. Spoken (written) like a true hoon!!
I’ll keep investigating.
Thanks anyway.
Excuse me, may i ask you a few questions? what will happen if i took Exhaust pipe off but leave catalytic converter as it be.
is it bad ? because if i put slip on exhaust with catalytic converter on a sound didn't change and if i replace it with some link pipe to header it too loud for me. it's Yamaha MT-10 it (would be great if you can give me some advices.)
Hi mate, it shouldn't be an issue. Most of the work has been done before the muffler. The catalytic converter will kill decibels so I'm not surprised that you are disappointed with a slip on.
it won't hurt the engine right ?
That is a question for Yamaha mate, it would be irresponsible of me to suggest otherwise.
The stock exhaust on the XS1100 is about the best you can get-which makes replacing them a royal PIA. The only viable replacement here in the States is the Mac 4 into 1 but I'm not giving up my center stand. My headers are okay, it's my mufflers that look like something out of Mad Max.
A PO drilled out 4 holes in the back of each muffler to make it louder-could that have possibly affected flow? I plugged them with jack bolts to get the stock mufflers back to original form but now I'm tempted to remove them because they look like crap. Come to think of it my whole bike looks fairly rough. Good mechanically-but it'd be nice to someday do a little cosmetics.
+James Robert I've seen photos of your bike on Facebook, I think. I agree with you about the XS11 pipes, they provide a good broad power spread. Got to love PO's, thanks for watching, Andy
'PO's' either means 'previous owner' or 'pissed off'. Probably both in most cases. I'd like to find some mufflers that match the pipes and try to weld some mounting brackets on. Not sure if the crossover pipe would be possible to do or whether it would help get the same performance spread as the stock set.
+James Robert there is a man in Germany who makes stainless steel reproductions
hi. I just decided to pull out my dad's old yamaha xs eleven special because he died when I was 5 years old and sat in one of our barns for over 25 years. I'd like to fix it and get running and make it street legal, then slowly make it look new again. any advice? no one around me will even touch it or give me advice on it. not even the dealers.
+truenorge10 G'day mate, thanks for tuning in. My advice would be to join the forums, US, Australia and U.K. Also their Facebook pages. There is a wealth of knowledge and a passion to support anyone wanting to get these great classics back on the road. Your motivation is commendable and your dad would be proud of you. If you have any specific questions don't be afraid to ask, if I can't answer them I should be able to point you in the right direction. Also look us up on Facebook, you can message me from the page. Andy
Andy- where did you get the 4-1 exhaust from?
G'day mate. I purchased it 2nd hand along with a box of other bits and pieces from an on-line auction site. the muffler was purchased from Motorcycle Exhaust Professionals in Queensland.
removing back pressure is only good for engines that are ALWAYS running in the high rev ranges, removing the back pressure WILL cause the engine to loose a lot of mid range torque and can cause miss firing in some cases. if you dont believe me then do some dyno testing before and after you remove the back pressure
You didnt mention anything about TAPERED exhaust pipes and TAPERED baffles. Hot exhaust gas wants to expand and will travel much faster thru a tapered pipe/baffle than a straight one. As the exhaust pulse (high pressure/low speed) enters the pipe, it wants to move toward the larger less restrictive area of the taper, which causes a low pressure area behind that pulse, which helps the following interval high pressure pulse to enter the pipe, thus scavenging happens helping the engine to BREATHE. That's the reason that most all exhaust muffler systems are TAPERED, such as the one on your bike. There not just for SOUND.
del boy should watch this
Why? He'd just want to fill it with MIG wire lol
correction : "back pressure is bad, always... unless you drive at exactly the right number of RPMs according to the timing of your back pressure, always"
Sounds like you should always take the baffle out of you can?
But Andy, you didn't mention the EXUP Valve... 😁
No I did not. I didn’t even think about it. My mind is fixated with older bikes.
@@ANDY5
Ain't none of us as young as we used to be. 😁
No dead cat up are pipes , there clean
You don't talk like an automotive engineer. You might want to check with one. Back pressure is used by exhaust designers to help the valves do their job more efficiently
This is why most 4-1 are actually 4-2-1 if you cut them up and look internally :)
andy if it were me I would take the Tasmanian outline use the Tasmanian cartoon character if you could without copyright infringement or something close to it on a motorcycle with your name that would definitely Define your artwork or use you your face on the Tasmanian body the world win and a motorcycle that would be awesome
Hi Paul, yeah that would be really cool. I used a pick of a Taz on a bike as a thumbnail when I posted about a ride I did with my daughter a while back. Not too sure how I'd go fighting Warner Brothers though. Thanks mate.
"Fresh air is drawn into the cylinder by a pressure differential, a vacuum left in place of the withdrawn piston. Just dont say it was SUCKED in....mother nature will get ornery."
It's about $20 worth of stainless steel. That people pay $500 for
& don't blame the dog
It wasn't the dog who farted, was it?
Yes it was...honest
@@ANDY5 No sir.
can't hear u man, i put the volume to maximum and then that intro....
Fire the guy who's editing ur videos
I don't know, if the engine doesn't suck in air, you wouldn't mind revving the engine to about five grand and sticking your noodle in the carb would you? perhaps another video, behind a curtin please, just leave your face above the screen so we can catch your expression!
+David Rogers yes the noodle would disappear rapidly as the air FLOWS into the low pressure area. Thanks for tuning in, Andy
You have some exhaust info down, some you are off, you spend too much time trying to over complicate your explanations. Also vacuum = suction, venturi affect takes place because the engine is pulling air through the carb. place your hand over any carb and you will feel the suction. I get what you were attempting to explain but again you're off the mark. Another thing to mention is that like others have stated back pressure can have great affect on low/mid range torque something very important for towing etc back pressure can also reduce fuel consumption. I would advice you get back to basics and learn a wider variety of systems before you start trying to "teach" because at this point you are only spreading an off base opinion. Cheers
good video, but way to complicated for no reason and tend to waffle on about the same thing .
You are very poor at explaining things. I lose confidence when you say the first stroke is not suction, of course it is. Suction is created with differential pressure and tthe gas is drawn from high to low pressure. When you suck through a straw you create a negative pressure in your mouth. .....Then you seem to want to put your own Ausi slant on every else and I am sorry, it is a muddle and teaches me nothing.
+Allan Byrne hi Allan, I'm sorry if I didn't explain myself very well. The point I was trying to make is that an engine doesn't work like a vacuum pump. Air isn't sucked into the cylinder but actually flows in at whatever atmospheric pressure is present at that elevation. That's why elevation has an impact, lower pressure = less air and therefore less oxygen available for combustion. Andy
I just watched this back and I am struggling to see what your point is? I said twice that air is introduced by pressure differential. I also can't find the "Aussie slant" you're referring to, it is just basic international engineering principles. I think I detect a hint of xenophobia and I am now doubting that it is me that is creating a cognitive block.
The atmospheric pressure has no bearing on the principle of "suction", that of a medium flowing from a high to low pressure area. To be exact, at a higher altitude the air is just less dense, as there are fewer oxygen molecules present, making breathing difficult.
I am trying to design a baffle for my old Honda NV400 and getting information is both difficult and contradictory. I am beginning to think there are as many opinions as there are bikers and that it will be a process of trial and error for me.
My one hope is that I can find one, take a look and copy it, but the bike is rare, although the early VT500 is similar.
+Allan Byrne I have been trying to explain that what I am saying is exactly what you are saying , in terms of differential pressure. Copying what others have done is always a good strategy, assuming they got it right. Andy
Sorry mate, I thought you were having a go at me. As I said, delicate balance between flow and velocity, I think that is where the "back pressure" misconception comes into it. You require enough restriction to promote velocity but want to avoid back pressure, it is an engineering fact. It's not that everyone is wrong, it is just that a large number who don't understand fluid dynamics and the principles of flow and pressure have difficulty understanding why you need any restriction at all. Look into Bernoulli's work and study his principles.