EGT difference question
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HDF Community Team
Joined: Dec 2005
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From: NC USA
EGT difference question
With a dual channel pyrometer (or whatever the dyno/tuner guys use), at what exhaust temperature differential between front and rear cylinders would you suspect an issue?
It's a carbed bike so I'll skip the long story but it's basically stock. Front runs avg. 75f hotter than rear, no signs or symptoms of an intake leak.
It's a carbed bike so I'll skip the long story but it's basically stock. Front runs avg. 75f hotter than rear, no signs or symptoms of an intake leak.
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you are worrying about small potatoes. first and foremost, they will never run the same as there are too many variables and no engine makes a perfect hit on every cyl every time and you will never notice it. you can get closer with fuel injection since the fuel delivery is timed but a carb, not so. look at how the engine is fueled, frt cyl pulls in and when the valve shuts, instant flow stoppage, when the rear valve opens, instant flow reversal and fuel left for the front is pulled into the rear, remember the 45* separation between the cyl's.
even on industrial engines where you can control each cyl, you will never get them to run the same. each cyl carries its own load based off compression, temp, fuel charge and the drag off the other cyls. on the old cooper's, we shot for 100psi diff'l between cly, yes, we used a bmep pressure gauge and not a pyrometer.
even on industrial engines where you can control each cyl, you will never get them to run the same. each cyl carries its own load based off compression, temp, fuel charge and the drag off the other cyls. on the old cooper's, we shot for 100psi diff'l between cly, yes, we used a bmep pressure gauge and not a pyrometer.
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HDF Community Team
Joined: Dec 2005
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From: NC USA
Couple things I failed to mention - first, it's standard touring head pipes so there's no way to place the rear sensor for an accurate reading unless the left pipe is blocked off (which could also change things). With the split being an extremely short 90 so near the head, blocking the right down pipe would have a similar effect I'm guessing. Also, I didn't mention the actual temps, which when averaged, amounted to only 15-18% differential.
I knew the readings for egt and afr would be "wide" on a carb engine and after some reading on aircraft tech sites I agree, the differential readings I got aren't even worth a second thought. Thank you bustert
I knew the readings for egt and afr would be "wide" on a carb engine and after some reading on aircraft tech sites I agree, the differential readings I got aren't even worth a second thought. Thank you bustert
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