Exhaust gas temperture
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Exhaust gas temperture
Having a discussion on gas engine exhaust gas temperature causing blueing of motorcycle exhaust pipes....Most say it's a lean mixture, some say a rich mixture....For this issue its a moderate part throttle like street riding, not full throttle racing......Some of you might have EGT gauges on engines with real life experience on this ? Thanks
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
Re: Exhaust gas temperture
Steels heat blue at temperatures between 550F and 625F. The exhaust gas exiting your chamber is significantly hotter. How is this anything but expected outcome? The only pipes I have seen that didn't blue were double walled.
- Paul
Re: Exhaust gas temperture
Pipes don't always blue because the airflow while ridding cools them.My LSR race bikes run wide open for 1-1/2 miles but don't really blue the bare steel pipes unless the bike does a lot of idling....Some exhaust pipe manufacturers say to avoid excessive use of the choke to avoid blueing....
Some say a lean mixture results in lower exhaust temperature? Some say just the opposite...
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
Re: Exhaust gas temperture
Not enough total timing will make them glow orange...lol. Also the plug wire looms melt and the water temp gets hot real fast.
Re: Exhaust gas temperture
What I've noticed on my cars is that during steady state cruising with say, 20* total, my EGTs were relatively high.
When I added 3 degrees, they went down.
My experience is that ignition timing has more of an effect on EGT than AFR.
When I added 3 degrees, they went down.
My experience is that ignition timing has more of an effect on EGT than AFR.
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Re: Exhaust gas temperture
Thanks!
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
Re: Exhaust gas temperture
How would lean or rich affect EGT at higher power ? Lean is hotter?
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
Re: Exhaust gas temperture
One dark zero degree winter's morning many years ago I fired up my Vincent V twin then went back indoors to suit up. When I came out a few minutes later I noticed the front pipe glowing dull red right down to the junction with the rear. I opened the front idle screw 1/2 turn and the glow went away...
Felix, qui potuit rerum cognscere causas.
Happy is he who can discover the cause of things.
Happy is he who can discover the cause of things.
Re: Exhaust gas temperture
Watch the muffler on a Briggs when you turn in the mixture screw with it running WOT.
Jim
Re: Exhaust gas temperture
That Vincent have Amal Monobloc's? Opening the idle mixture screw makes the idle mixture leaner...MadBill wrote: ↑Mon Oct 15, 2018 9:50 pm One dark zero degree winter's morning many years ago I fired up my Vincent V twin then went back indoors to suit up. When I came out a few minutes later I noticed the front pipe glowing dull red right down to the junction with the rear. I opened the front idle screw 1/2 turn and the glow went away...
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
Re: Exhaust gas temperture
MadBill wrote: ↑Mon Oct 15, 2018 9:50 pm One dark zero degree winter's morning many years ago I fired up my Vincent V twin then went back indoors to suit up. When I came out a few minutes later I noticed the front pipe glowing dull red right down to the junction with the rear. I opened the front idle screw 1/2 turn and the glow went away...
That Vincent have Amal Monobloc's? Opening the idle mixture screw makes the idle mixture leaner...Or the manual magneto advance,if fitted, could have been left in the retarded position...
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
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Re: Exhaust gas temperture
If the air/fuel ratio is very close to optimum (for specific weather conditions) then a slight change in mixture will produce an almost imperceptible change in EGT.
If mixture is either excessively lean or rich, the burn will occur at a later crank angle. An early burn, as with advanced timing, will reduce EGT but will raise chamber temperature. Late timing, or late burn, will lower piston temperature but will raise EGT.
EGT is difficult to measure accurately and has little effect on a four stroke engine. But EGT is quite important on a two
stroke engine in order to properly tune the pipe scavenge.
Re: Exhaust gas temperture
No, it was a '53 Black Shadow with 1 1/8" separate float Amals, which had fuel control idle mixture screws. Also it had an automatic advance mag.Truckedup wrote: ↑Tue Oct 16, 2018 6:33 amMadBill wrote: ↑Mon Oct 15, 2018 9:50 pm One dark zero degree winter's morning many years ago I fired up my Vincent V twin then went back indoors to suit up. When I came out a few minutes later I noticed the front pipe glowing dull red right down to the junction with the rear. I opened the front idle screw 1/2 turn and the glow went away...
That Vincent have Amal Monobloc's? Opening the idle mixture screw makes the idle mixture leaner...Or the manual magneto advance,if fitted, could have been left in the retarded position...
Felix, qui potuit rerum cognscere causas.
Happy is he who can discover the cause of things.
Happy is he who can discover the cause of things.
Re: Exhaust gas temperture
Today no one starts up a Vincent and walks away unless there's an armed guard standing over it..MadBill wrote: ↑Tue Oct 16, 2018 3:32 pmNo, it was a '53 Black Shadow with 1 1/8" separate float Amals, which had fuel control idle mixture screws. Also it had an automatic advance mag.Truckedup wrote: ↑Tue Oct 16, 2018 6:33 amMadBill wrote: ↑Mon Oct 15, 2018 9:50 pm One dark zero degree winter's morning many years ago I fired up my Vincent V twin then went back indoors to suit up. When I came out a few minutes later I noticed the front pipe glowing dull red right down to the junction with the rear. I opened the front idle screw 1/2 turn and the glow went away...
That Vincent have Amal Monobloc's? Opening the idle mixture screw makes the idle mixture leaner...Or the manual magneto advance,if fitted, could have been left in the retarded position...
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire