Butterfly valves

Growler

Growler

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Today, 05:18
Joined
Jan 19, 2018
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Age
67
Location
Uk
First Name
Kev
My Ride
Triumph thunderbird commander
Could any one answer a question for me !!
Can you run your bike without this in the exhaust as I’m thinking of changing the pipes I have a 14 plate 1700 commander and the valve is in only one side and what does it do
Cheers growler
 
I believe it is to reduce or eliminate popping on deceleration.
 
It opens up at WOT to reduce back pressure and in theory increase performance. I know the T'bird gets considerably louder when onto the gas and this opens. I don't know if removing it will give you any gains or just mess up the ECU as you will be decreasing back pressure. It may very well do as VA Bird said as well. Big Triumph mystery.
 
Qship said:
It opens up at WOT to reduce back pressure and in theory increase performance. I know the T'bird gets considerably louder when onto the gas and this opens. I don't know if removing it will give you any gains or just mess up the ECU as you will be decreasing back pressure. It may very well do as VA Bird said as well. Big Triumph mystery.
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VABird said:
I believe it is to reduce or eliminate popping on deceleration.
Click to expand...
VABird said:
I believe it is to reduce or eliminate popping on deceleration.
Click to expand...
 
Ok all many thanks for your reply’s to my question on butterfly valves
 
Growler said:
Could any one answer a question for me !!
Can you run your bike without this in the exhaust as I’m thinking of changing the pipes I have a 14 plate 1700 commander and the valve is in only one side and what does it do
Cheers growler
Click to expand...
Mine failed and the ECU put the bike into Limp IN Mode and ran rough and lit the Engine light. Cost me $984 at the stealer to replace, don't mess with it
 
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With new valve, still pops, but i don't mind. BTW I have Vance and Hines pipes, so it's loud anyway. With the new valve, it is quieter when cold, but I wouldn't care if it wasn't.
 
New here so please be gentle. I recently purchased a 14 T-bird LT and I am surprised at the amount of over run backfire and the extremely load upper engine noise( intermittent) . the bike dose have loader Triumph pipes
Thanks in advance for your advice
 
G-man
Welcome to the forum!
Also have a 14 T-Bird LT, purchased used w/2500 miles which had 1 year of warranty left. Stock Triumph pipes? Not sure I understand "Loader Triumph Pipes". How many miles on it thus far? If stock left muffler is more restrictive than the right (I might have that reversed, my manual is tucked away in my shed/shop)....also the left side has the EXUP valve which requires occasional adjustment. If they are not stock there is a download (for less restrictive exhaust and air) to the ECU which can be done by a dealer which will help, but not eliminate decel popping.

There are numerous articles out there on the engine noise, some do, some don't. Why is what we don't know and there are several schools of thought. Personally I have my own thoughts on the subject and won't bore you with my comments/details at this time.
 
I don't believe the left and right pipes are different, except for the valve, it is just that with the valve closed, all of the exhaust goes through the right pipe and that is why it is quieter, single exhaust instead of dual.
 
You are most likely correct....could swear I read restriction/airflow is different in stock pipes. Must be the ADD again.
 
If you have the Triumph TOR(Triumph Off Road) pipes, then yes they are a little louder than stock. You must have the Triumph low restriction foam air filter before they can do the TORs tune. I have them and yes there is a fair amount of popping on decel. I believe there is less with the stock tune, but what's the point of having higher performance pipes without the performance?
These engines tend to be a little louder than most are accustomed to and quite a few T'bird and Commander owners have had the pistons and sleeves replaced under warranty. Sometimes the noise comes back, sometimes it doesn't. This is well known on some "other" forums. Mine has a little noise when under light load, but not very noticable to me. it hasn't become a problem and there are lots of T'birds out here with many trouble free kms on them.
BTW, welcome to TT from the Eastern side of Canukistan
 
thanks for the info guys. yes they are Triumph off road pipes with the Triumph foam air filter. the Local dealer just installed the most current map for the pipes. is there a way to check if the exhaust butter fly vales are working properly
 
If it isn't working, the engine light will come on, that's what happened to me. Cos $984 to replace the servo that controls the valve. Dealer said they had to take the whole bike apart, i told them I didnt care what it sounded like (couldn't really tell the difference) but the computer went into limp in mode and they couldn't reset it with the valve not working. (insert angry icon here)
 
Thanks Rusty, I took it a part tonight and while it was removed from the exhaust I cycled the ignition. Mistake, I think is no longer in its proper orientation. It was a bit of a challenge getting back together . Once back together the Check engine light was on but now 95% of my over run back fire is gone? The servo still cycles. Ill put up with the check engine light , No overrun Backfire.... nice
 
Update. After a bit of adjusting the cables on the Exhaust Butterfly Valve the check engine light is out and overrun backfire is at a all time low, 98% gone. Not really sure what I did but it worked.
 
Glad to hear you got if fixed Gman. My problem wasn't the vave itself, but the servo that operates it using the cables. had to replace it, only because the engine will not run right with the "engine" light on. also, i don't mind the backfire, give me street cred...LOL
 
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