Bored winter thoughts.....R1200s headers de-cat'ing

StreetFlatTwin · Post by **StreetFlatTwin** » Sat Jan 26, 2013 11:16 pm

Hi I am looking through the list of stuff I fancy doing to the R1200S and removing the cat is one I am thinking about.

I'd rather buy a replacement and gut them allowing my to swap back when I sell the humbug, so a couple of questions.

Are the R1200S headers unique to the 12S or are GS, GS Adventure, RT headers a straight swap?

Also is it best to open the cat section of the exhaust remove it then weld back up-job done?

Would I need to remove the lambda or will it run as well (with freeing reving etc) without the cat?

Boxered · Post by **Boxered** » Sun Jan 27, 2013 1:39 am

A catectomy has been performed before ( Roloo ) And remus do a splendid replacement cat-less header set which I have on my bike. It is worth noting that the link pipe is done away with with the Remus system, but not with any other (hpe or Akra)system that I am aware of. The remus headers include provision for lambda sensors, but you can just blank them out ( I still have them )

Steve

Droptarotter · Post by **Droptarotter** » Sun Jan 27, 2013 3:07 am

I have a Ti Akro on mine.....it does have the O2 sensor hole as most of the aftermarket pipes do.

Roloo did gut the system, but you will find out it is not such an easy job on the 12S due to the interior of the cat is made of hardtoremovum.

The best way to go is a complete exhuast system.
I prefer the Akro or if you can find it, an HPE.
Maybe check with Sandbar to see what he has.

The Akro on a 12S sounds like the bike should!

Cheers

HerrFlick · Post by **HerrFlick** » Sun Jan 27, 2013 3:21 am

Droptarotter wrote: ...interior of the cat is made of hardtoremovum. Cheers

"hardtoremovium".

Larf chuckle snort ...

Another exotic metal I can put with Unobtanium.

.

exoticices · Post by **exoticices** » Sun Jan 27, 2013 5:47 pm

I hate cats (except the four-legged ones). Removing the cat on an R1200S makes it 'feel' significantly better and improves the throttle response too. It's a 'must do' really.

However... not many people make aftermarket headers anymore (i.e. they're expensive). The Akra system is probably 'the best' but (retail) they're only full system and eye-watering expensive for what at the end of the day is a bit of pipe. There's an Italian company who also sell headers as part of a full system but they're just as expensive. Wunderlich sell the old Remus headers seperately at a slightly less painful price, and Rainbow BMW were recently selling them a bit cheaper than other suppliers.

Another option is to have some custom headers made (OS Pipes for example), which would probably be around the same price as Wunderlich/Remus and you could have any routing you want (like the old under-sump HPE headers). But you'll probably have to take the bike to them for measuring up, so it may not be convenient.

I looked at a catectomy but was advised it's a lot of hassle. As said, it's made of 'hardtoremovium'. The easiest way would be to cut the whole section out and replace it with hollow tube. Either way, the headers would look a bit 'Frankenstein' afterwards and would need painting or coating or similar. There'd probably be little or no cost saving over Wunderlich headers and you wouldn't have the standard headers anymore.

I looked at the GS/R/etc. headers. The OE (cat) headers are different part numbers. I think (99.9% sure) that the routing is the same, the diameter at the exhaust port is the same, but the diameter at the endcan end is smaller than the R1200S. I don't see any reason why they wouldn't still 'work', but you'd be restricting gas flow(?), so presumably loosing a bit of power?

As for lambdas, some seem to leave them in, some remove them. I think the consensus seems to be to remove them if you've having a PC/remap, otherwise leave them in.

If you're not going to have a PC/remap, then it's probably worth getting one of those booster plug gizmos. They seem to do most of what people want at a fraction of the price.

If you happen to have the cash lying around or down the back of the sofa, a full Akra is probably the easiest & nicest way to go - it does make the 12 sound like a 'proper' bike. The Wunderlich headers with OE endcan is much cheaper and nearly as good. I'd only attempt a catectomy if you can do it yourself and like swearing a lot!

StreetFlatTwin · Post by **StreetFlatTwin** » Sun Jan 27, 2013 6:09 pm

Thanks for your in depth reply.

I should have said my bike has the Remus twin round outlet end can and has a booster thingamajig (the one that fools the bike into thinking its colder (hotter??) so give a bit more fuel) already fitted.
There is a stainless steel exhaust fabricator not far from my parents house so it wouldn't be that hard or expensive (I hope) for them to de cat or chop and replace with an empty pipe BUT I'd still want a spare set of header pipes to allow me to swap back should into to sell the humbug.

Do Wunderlicht or Remus headers look the same as OE?

TIM EVANS · Post by **TIM EVANS** » Sun Jan 27, 2013 6:52 pm

StreetFlatTwin wrote:Thanks for your in depth reply.

I should have said my bike has the Remus twin round outlet end can and has a booster thingamajig (the one that fools the bike into thinking its colder (hotter??) so give a bit more fuel) already fitted.
There is a stainless steel exhaust fabricator not far from my parents house so it wouldn't be that hard or expensive (I hope) for them to de cat or chop and replace with an empty pipe BUT I'd still want a spare set of header pipes to allow me to swap back should into to sell the humbug.

Do Wunderlicht or Remus headers look the same as OE?

StreetFlatTwin · Post by **StreetFlatTwin** » Sun Jan 27, 2013 7:41 pm

They look gorgeous what ones's are they in the photo??

Droptarotter · Post by **Droptarotter** » Sun Jan 27, 2013 7:54 pm

Check this thread..............

http://forums.pelicanparts.com/bmw-r110 ... 1200s.html

Cheers

TIM EVANS · Post by **TIM EVANS** » Sun Jan 27, 2013 9:41 pm

StreetFlatTwin wrote:They look gorgeous what ones's are they in the photo??

remus/wunderlich

exoticices · Post by **exoticices** » Mon Jan 28, 2013 11:21 am

StreetFlatTwin wrote:Thanks for your in depth reply.

Sorry, I get carried away sometimes!

StreetFlatTwin wrote:I should have said my bike has the Remus twin round outlet end can and has a booster thingamajig (the one that fools the bike into thinking its colder (hotter??) so give a bit more fuel) already fitted.
There is a stainless steel exhaust fabricator not far from my parents house so it wouldn't be that hard or expensive (I hope) for them to de cat or chop and replace with an empty pipe BUT I'd still want a spare set of header pipes to allow me to swap back should into to sell the humbug.

That's good - have a chat with the fabricator and see what he suggests. Let us know what he says.

Do Wunderlicht or Remus headers look the same as OE?[/quote]

The Wunderlich/Remus don't have that balancer tube at the front. They do look better made than the OE ones, but they do 'tarnish' quickly, meaning you have to keep polishing them if you want them to look shiny.

exoticices · Post by **exoticices** » Mon Jan 28, 2013 11:28 am

This is what RoLoo did:
viewtopic.php?t=8358

StreetFlatTwin · Post by **StreetFlatTwin** » Mon Jan 28, 2013 11:49 am

I just spoke to Motorworks they want £280 for 2nd hand standard headers

Then I would probably decat myself but would need to pay the exhaust fabricator to weld them back up........

Just to check OE headers are stainless yes?? (I know the exhaust fabricator will ask!!!)

RoLoo · Post by **RoLoo** » Tue Jan 29, 2013 7:55 pm

StreetFlatTwin wrote:
1) I just spoke to Motorworks they want £280 for 2nd hand standard headers

2) Just to check OE headers are stainless yes?? (I know the exhaust fabricator will ask!!!)

1) ...bought those headers in pictures for 100 €uro...

2) ...yes...

Using HPE headers these days, and sold those cat-less-headers.