De cat or not?

[farmhand]

Hi, I was thinking of taking out the exhaust cat and was wondering what the pro's and con's are? I also have an accelerator module fitted are the two mod's compatable?
Thanks in advance for any help.

 

[Peak Rider]

There's a reason catalysts are on vehicles these days. It has to do with the air we breathe.

 

[farmhand]

I don't have any kid's I consider that my carbon offset

 

[SURMANATOR]

De Cat will bring you extra torque in the mid range the engine will spin up faster fuel consumption will improve will be less jerky at idle / filtering speeds. DeCat worked for me

 

[Sgt Bilco]

More low down torque, about 5 bhp more, engine will spin up better, get a nice poip on overrun and if anything, your fuel consumption will be down slightly because you'll want to ride faster

It's a great mod to do and don't bother with an end can for performance because that just gives you expensive noise.

 

[Rasher]

De Cat will bring you extra torque in the mid range the engine will spin up faster fuel consumption will improve will be less jerky at idle / filtering speeds. DeCat worked for me

As above, the Accelerator module should help as with the cats removed the bike may run a shade weaker and the module will help compensate.

Same setup as me and it definately helps the bike out a bit, most notably in the mid-range.

 

[Schtum]

I think you should read this thread.... http://www.ukgser.com/forums/showthread.php?t=282959

 

[GB.]

Are you thinking of swapping headers or cutting the cat open and re-welding? I had catless remus headers linked to Leo V end can. Now it made more power but was to raspy for my tastes, not a deep enough sound (I ran no Decibel killer) I have Techlusion fuel controller to keep the air fuel ratio correct by the way. Any way,I done some research on exhaust tuning and found that the balance pipe seems to be quite important to the running of these engines (and most others apparently) So I didn't like the idea of cutting the cat out and rewelding as the gas velocity would drop when it reached the large open catless part, then be asked to squeeze back down to get to the end can, great for a two stroke expansion chamber, but not a slow revving four stroke. So I used the front balanced stock headers with a catless Y piece, this keeps the gas speed up but removes the restriction at the same time, the result is great sound, real good bottom end and a kick at the top end all better than stock or catless with no balance plus better mileage aswell.
I personally wouldn't by an aftermarket system with no balance pipe.

 

[(RIP) Miff]

My 05 1200GS has Remes decat headers, Akrapovic end can (no baffle) and an accelerator module thingy. It was like this when I bought it.

My mate reckons it's faster than my previous 05 1200GS (and that was standard apart from the can being gutted) as he can't keep up on his Varadero. He could keep up with the other GS.

 

[ianp5uk]

Are you thinking of swapping headers or cutting the cat open and re-welding? I had catless remus headers linked to Leo V end can. Now it made more power but was to raspy for my tastes, not a deep enough sound (I ran no Decibel killer) I have Techlusion fuel controller to keep the air fuel ratio correct by the way. Any way,I done some research on exhaust tuning and found that the balance pipe seems to be quite important to the running of these engines (and most others apparently) So I didn't like the idea of cutting the cat out and rewelding as the gas velocity would drop when it reached the large open catless part, then be asked to squeeze back down to get to the end can, great for a two stroke expansion chamber, but not a slow revving four stroke. So I used the front balanced stock headers with a catless Y piece, this keeps the gas speed up but removes the restriction at the same time, the result is great sound, real good bottom end and a kick at the top end all better than stock or catless with no balance plus better mileage aswell.
I personally wouldn't by an aftermarket system with no balance pipe.

Interesting so does it improve a lot and get some top end like the new GS or does it still remain a bit breathless but a tad better than standard?

 

[farmhand]

I'm just thinking of cutting the stock system open taking it out and re-welding it, if it gets any more complicated than that and could have knock on effects I don't think i will bother. At the moment i can't afford to put alot into it and deffinately can't afford a damaged engine. By the way I would be keeping standard exhaust can.

Thanks for the advice.

 

[Rasher]

This is a common mod so I can't see it causing issues.

I went for a de-cat header set as I found them used for £100, but new ones can be found for under £200 and you will get half that back at a later date.

Hacking your exhaust open is likely to devalue the bike, however if you can do it yourself will cost nothing, and I doubt future prosepective buyers would notice this "enhancement" unless you tell them.

I know a great welder who could have sorted mine, but decided I would rather have the option of reverting to standard come sale time.

 

[GB.]

Interesting so does it improve a lot and get some top end like the new GS or does it still remain a bit breathless but a tad better than standard?

I've been impressed so far, cruise at a ton and open it up and it pulls forward really hard and the same goes for 80mph as well, really does go well now

 

[Allan F]

De Cat

Take it out Boss. It's worth doing.

 

[(RIP) Miff]

If you gut the original down pipes, you can weigh in the cat. They are worth a fair bit due to the precious metals in them.

 

[farmhand]

Thanks for the info lad's, I have had a look around but can't find a how to thread with pictures any help?

 

[G5RJO]

Easy job.

Undo the bolt securing the rear can to the frame.

Undo the bolt that joins the rear can to the header (note which way it goes and the angle for re-assembly later).

Remove the rear can.. It will need a bit of a 'waggle' to get it off the header pipe.

Unplug the two lambda sensors, follow the wires from the sensors on each side of the headers up and under each cylinder and disconnect.

Undo the nuts at each header connection to the cylinder.

Undo the bolt that supports the header at the rear of the sump.

Header will come off now with a bit more of a waggle (technical term)

DONT BE TEMPTED TO GO POLISHING IT ALL JUST YET.

There will be an obvious mark where the mounting strap went, its the thicker part of the pipe under the sump.

Get the header cut where the strap goes. If its cut where the strap covers then nobody will be the wiser. The local exhaust place will do it with a pipe chop saw in seconds. (Don't try it with a hacksaw...It will p you off very quickly).

The two ends of the header will have a metallic honeycomb affair inside. I used a 10mm drill to knock loads of holes in each half then a hammer and chisel makes easy work of removing the bits... its not that difficult.. get as much out as you can... That means all of it!!

Take it back to the exhaust place and get it welded back together. Hand the man a £10 beer token and then reassemble everything.

You can polish it all nice and shiny before putting it back on if you want. The strap will cover the weld line up so nothing is evident.

Ride the thing!

Probably do the lot in an hour tops!

Hope that helps.... Sorry no photos but its dead easy.

Roger.

 

[farmhand]

Thanks for that Roger will get it sorted

 

[(RIP) Miff]

My 05 1200GS has Remes decat headers, Akrapovic end can (no baffle) and an accelerator module thingy. It was like this when I bought it.

My mate reckons it's faster than my previous 05 1200GS (and that was standard apart from the can being gutted) as he can't keep up on his Varadero. He could keep up with the other GS.

I've just remembered, it wheelies off the throttle much easier too. So it must have more poke...

 

[Fanum]

There's a reason catalysts are on vehicles these days. It has to do with the air we breathe.

Do you think that the energy and poisonous/rare/dangerous metals and chemicals that go into a Catalytic converter are less or more costly to the environment than the increase in pollutants that not having one causes?