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To de-cat or not to de-cat that is the qu...........
Posted: Fri Feb 29, 2008 1:14 pm
by Cobbster
Hi all,
As the title suggests I'm thinking of de-cating the beast and fitting a Y peice. Makes and models aside, I was wondering what the general consensus was to the benefits that de-cating gives. I've heard that it gives better breathing to the engine, better low down power delivery ect ect.
Apart from the good stuff is there any negative points to doing it?. I'm pretty handy with a decent tool kit so doing the job holds no fear its mainly a case of does the cost outway any benefit.
Thanks for any input, Cobbster.
Posted: Fri Feb 29, 2008 1:20 pm
by winger
Well the old hands have heard it before,but haveing a stock filter and cat on your bike,is like haveing your hand over your mouth and your finger up your bum!! see how well you operate!!,infact i'd make it capital offence running an S with a cat,horrific

Posted: Fri Feb 29, 2008 1:31 pm
by Cobbster
Great analogy Winger, I tried the hand over the mouth but the other bit I'll leave.
I would like to think that its just a case of changing the cat for a y peice, ie no monkeying about with fitting chips or power comanders. I also intend using my stock end cans.
Thanks, Cobbster.
Posted: Fri Feb 29, 2008 2:06 pm
by The Teutonic Tangerine
Question. My "S" is Registerecd in 1998 ("R" reg). Does it have a Cat or is the box just a collector box. Can you tell from the picture
http://i152.photobucket.com/albums/s190 ... xhaust.jpg
Posted: Fri Feb 29, 2008 3:16 pm
by JoeC
Cobster ... you should not need to doing anything else to the engine/electronics when fitting the Y. However, with any bike, the more you change the air/exhaust bits then you may want to get the bike Dyno'd.
I ran my S with a Y and K&N filter (see the For Sale section for K&N) and standard exhaust with no problems. However, if I were to have put on a different exhaust then I may look at getting it Dyno'd.
Got ahead, fit a Y and you will appreciate the better engine and noise but be aware that the engine may 'pop' on the overrun but they all do that with a Y - some more than others. Sounds pretty good though, especially when in a tunnel.
Teut Tang ... the picture shows a bike with a cat - big sqaurish, heavy thing under the bike.
Posted: Fri Feb 29, 2008 3:53 pm
by Cobbster
Thanks JoeC,
Thats basiclly all I needed to know, the cat cometh off. Probably order a y peice next week unless someone has one kicking around who wants some beer tokens for it
Thanks, Cobbster.
Posted: Fri Feb 29, 2008 4:13 pm
by JoeC
Stick a WANTED posting in the For Sale bit and see what comes back. You have to post back quickly to say you want one if there is one for sale as they are normally sold pretty quickly.
Posted: Fri Feb 29, 2008 7:31 pm
by winger
TTT it's a cat all right,i haven't stopped cringing from when you put your photos up,the only pipe thats ever had a collector box was the Remus Rich knows more about e'm then i a do,and almost certainley if your bikes 'R reg' it's an ex press bike.
Cobbster
I ran my S with a K+N and then a SJ air filter and full system from front to back for what ? 4/5 years it ran fine,just that when i had a P/C put on ironed the blips out,that had grated on me after all those years(had a flat spot just over 4 thousand)
Posted: Mon Mar 03, 2008 9:31 am
by Cobbster
Hi all,
Bits ordered this morning, can't wait to get the spanners out.
Cheers, Cobbster.
Posted: Mon Mar 03, 2008 9:58 am
by The Teutonic Tangerine
"Teut Tang ... the picture shows a bike with a cat - big sqaurish, heavy thing under the bike."
Thanks I suspected that.
"if your bikes 'R reg' it's an ex press bike."
interesting theory but not, I think, supported by the paperwork that came with the bike. I will try to investigate further.
Posted: Mon Mar 03, 2008 10:17 am
by Blackal
Anyone know of a supplier of cat-replacement pipes for the Lazer exhuast as fitted to the Mk 2 Boxercup?
Al

Posted: Tue Mar 04, 2008 8:10 pm
by POB
Al, I have Lazer cans and the Remus Y. All went together spiffingly. Running it with a K&N and Lazer EPROM chip. Mix is about right, although more by luck than judgement I think.

Re: To de-cat or not to de-cat that is the qu...........
Posted: Wed Mar 05, 2008 7:41 pm
by budman200210
Cobbster wrote:Hi all,
As the title suggests I'm thinking of de-cating the beast and fitting a Y peice. Makes and models aside, I was wondering what the general consensus was to the benefits that de-cating gives. I've heard that it gives better breathing to the engine, better low down power delivery ect ect.
Apart from the good stuff is there any negative points to doing it?. I'm pretty handy with a decent tool kit so doing the job holds no fear its mainly a case of does the cost outway any benefit.
Thanks for any input, Cobbster.
Hey Cobbster, ive just done mine, very simple.
I have'nt had it out properly to tell of any change, but Do it just for the sound, now my Lazers sound the nuts!
Aaron
Posted: Wed Mar 05, 2008 10:20 pm
by Cobbster
Hi all,
The cat is out of the building. Removal was simple, lots of 'Wobbly Dog' applied a couple of days before made sure things came apart easily. Fitting the Y section was a bit of a chew as the cross member was about 3mm too long. Chopped it down and it went in easy. The gaps between the headers and the Y pulled in ok and after a bit persuading the lamdba probe let go, all was done in about and hour. Iv'e still got a couple of finishing touches to do ie, the centre stand now clunks the bottom of the tourque arm, simple spacer job, and the side stand spring now touches the left hand header, adjustment. Discovered that I had a blown number plate light during assembly so a new bulb needed.
As with budman I have'nt had the chance to test ride yet but I should get out tomorrow. At first start up I noticed a big difference in noise, not loud just better, and tick over is'nt as lumpy as it was with the cat on. It seems to rev a bit more freely and second stage on the high rev lever wasnt needed to keep it ticking over from cold. I can only put this down to the engine being able to breath more easily.
The Remus Y peice seems to be made of pretty good quality SS but fabrication let it down a bit. Apart from having to chop down the cross member I had to re-tapp 2 of the holes. They were a bit burred up but luckly I had an M6 tap handy.
Let you know how I get on tomorrow, Cheers, Cobbster.
Posted: Thu Mar 06, 2008 2:59 pm
by Cobbster
Hi all,
Rode the S today and liked what I felt/heard. The engine seams to pick up better and it sounds brilliant. The weather conditions oop norf are'nt that good so did'nt get very far, 10 miles tops. Maybe after next week I'll get out and really stretch its legs.
As for the Cat, I'm keeping it for resale purposes, these y peices seem to go for good money on fleabay so should get a bit back when the 11S goes.
Thanks, Cobbster.