Exhaust Pipe Flap Valve Thingy

[MacJ]

Just had my silencer off on 64 plate (Sept 2014) RT to remove the wheel. [size=2px] The bike is outside warranty but is covered by the 'Assured Warranty' which I took out when the original expired.[/size]

[size=78%]While it was off I checked the valve in the exhaust pipe to find it seized solid. When the ignition is switched on I can hear the servo trying to move but nothing gives.[/size]

How many here have had this problem?
If so did BMW replace free of charge (outside warranty) or did you have to cough up the grand or so for new?


I am off to the dealers on Monday and would like to know what to expect from them.

[richardbd]

I had exactly the same issue - outside warranty.


Dealer got BMW UK to pay for parts (£1,200 from memory - they have to replace the entire downpipe) if I paid for the labour (less than £100)


No need to panic yet...

[Levisp]

May depend upon dealer. I have read on another forum of someone who's bike is in warranty and their dealer  said that BMW has refused a warranty claim. Don't understand this surely its either covered or not. I suspect there is more to it. The exhaust valve does seem to be a problem. Unfortunately on the LC bikes the valve is part of the downpipes. On the previous model it was a separate part and much cheaper to replace or remove. Progress !!

[guest2360]

Extended warranty doesn't cover the exhaust.

[LAF]

Just had my silencer off on 64 plate (Sept 2014) RT to remove the wheel.  The bike is outside warranty but is covered by the 'Assured Warranty' which I took out when the original expired.[/size]

[size=78%]While it was off I checked the valve in the exhaust pipe to find it seized solid. When the ignition is switched on I can hear the servo trying to move but nothing gives.[/size]

How many here have had this problem?
If so did BMW replace free of charge (outside warranty) or did you have to cough up the grand or so for new?


I am off to the dealers on Monday and would like to know what to expect from them.

Since the servo is working then that leaves cables.  It has to be moving from exhaust pressure or your bike would/should run very poorly so I can not see it being seized in the pipe solid.

Go to a BMW parts site and lok up the part in the parts breakdown to see what is what.  See where you can lube and maybe work cables to see if you can free it.

Here is a link so you can see the parts.  I would spray liberal amounts of what ever is your favorite rust/bolt loosening product and see what happens.

EDIT: Seems the link did not want to work. 

The YouTube is interesting. After seeing that I would use a product like seafoam or something to cut carbon, and clean that spotless. 

Of interest to me is what octane gas do you use? And how was the performance of the bike?  It would indicate that you would need a lot of exhaust gas to make that move if at all, and probably contributed to that carbon issue.

I know I will make it a point next tire change to look at it.

Again I would look at a part diagram so you can see how the cable system works and lube those also.

[David.]

Time to get the blow torch out, https://www.youtube.com/watch?v=j7iNstdAcoc, then some graphite lubricant.

[Casbar]

Been there and got the t shirt. You can try and free it, but it won't stay free for long. The only answer is getting it replaced. On my 2014 out of warranty BMW replaced mine last year. The tech did say, that if BMW wouldn't't replace it, he would leave it, as if its open then there will be no major ill effects. The replacement is £1200. If its stuck there will be an error code that shows up on service. You can disconnect the cables, then there will be no error codes. But when you sell, its really upto you if you tell anyone its stuffed and will need new headers. Not great news, but I would try BMW, some dealers replace the exhaust, some get nowhere.

[Cleverbee]

YOU HAVE TO DO WHAT TO REMOVE THE REAR WHEEL !
:eek: :eek: :eek: :eek: :eek: :eek: :eek: :eek: :eek: :eek:




just unscrewed​ the rear portion of the wheel arch on the LT...

[LAF]

YOU HAVE TO DO WHAT TO REMOVE THE REAR WHEEL !
:eek: :eek: :eek: :eek: :eek: :eek: :eek: :eek: :eek: :eek:




just unscrewed​ the rear portion of the wheel arch on the LT...

Yes since you need to remove the exhaust can to change a tire it would be a good time to check this item.

Before I would pay to have it fixed I would just buy a set aftermarket headers and call it a day.  Never have to worry over it again.

First choice would be to try a lube clean and maintain, after that pull it and live with the error.

Still have to ask why is it so carbon fouled?  Is it gas type/octane?  Or was something amiss that kept it blocked and just progressed worse?  Cable snap or hang up?

I hate to keep harping but a GS-911 will run this test for you and so many others it is worth the investment especially if you have a group to go in on it.

SeaFoam makes a fogger that works like nothing else.  Heat the bikes up, spray it down let it sit to work then fire it up.  You will not have to worry about mosquitoes but it will clean that carbon spotless.  It cleaned piston tops to almost new so that little bit in that pipe would be nothing for it.  I would try to clean and lube before replace

I will add it to inspect on rear tire change now. 

[blokeonthemove]

What does the flap actually do.

[LAF]

I believe it's main function is to cut down on noise.  However it also must add back pressure to the motor, but how much or how important I would not be able to guess.  I know without it, it would be more flow at certain times or area of RPM so I would think you would need to add fuel to make it richer.

[guest2360]

I understand it is to conform with EU noise levels .

[MacJ]

Flap working or not the bike is running beautifully and had I not removed the can I wouldn't be aware of the problem(?)
In response to LAF I don't believe its a carbon build up, I think it's corrosion that causes the issue. I have since removed the black plastic cover to have a good look at the mechanism and can clearly see the actuator cables moving fine. The flap mechanism could not be more firmly locked had I welded it up.
As the flap is an integral part of the headers the only solution is a complete replacement.
I shall be going to the dealers to seek a solution but if its not economical I'll just live with it. As the saying goes, 'If it ain't broken don't fix it'. Or if you own a BMW, 'If its broke you can't afford to fix it'.

[David.]

Could the headers be removed and the exhaust flow control valve cut out, then replaced with a straight through section of pipe welded in.

[B787MECH]

Sounds like removing the cables and either removing the butterfly or turning the shaft to the open position is the cheap answer


Sent from my iPad using Tapatalk