Decat - Noise Levels - Thoughts??

[fatbob]

It's a big fucking ball ache with the short akra , your mates will insist you ride at the back , I spent a shit load of money making loads of noise and a shit load more buying a proper system , which incidentally didn't sound as good as the AR system but to pass noise tests you'll be throttling the life out your bike

Eg had mine on a dyno with a baffle to us it oulton park and the bike lost over 20 bhp.........
So to summarize its loud or slow
Unless you don't do track days I wouldn't bother

 

[thompsp]

It's a big fucking ball ache with the short akra , your mates will insist you ride at the back

Agreed, I found it too much ...and so did they. These were the same mates that initially said "nah, you can never have it too loud!"

So to summarize its loud or slow Unless you don't do track days I wouldn't bother

Have to disagree. It's took some playing around, but using the variable baffle I had made, I have got similar power to without no baffle (only feels a minute bit less power) and I've got the right level of noise for me, my mates and the tracks. So, given the weight loss, extra low/mid grunt and sound, I'm very happy that I did this mod and would recommend it.
I still plan to take it to Hilltop in a couple of months (when it's dry/warm enough) to get the ECU Flash and really make the most of it though.

 

[DJUK]

Nah I don't do track days.

 

[RossHarper]

All my friends love how loud it is, other riders at meets are 50/50

 

[Docta13]

Nah I don't do trackdays?

U will. It's in our blood!!

 

[jack sprat]

HI thompsp,
jack sprat here can you please tell me who fabricated your baffle. Can I get one or the plans. I only do track days and I don't think I have used the bikes full potential as yet so I will not know any other (the slick pin is not in yet )
Regards jack sprat

 

[MickyC]

Nah I don't do trackdays?

U will. It's in our blood!!

Neither had I until I got the s thou, now I'm hooked

 

[DJUK]

All my friends love how loud it is, other riders at meets are 50/50

Im sure I'll like it, my really old suzuki sv650 has a not for road use (ART) exhaust, which sets car alarms off when I rumble past them. Haha. Just don't know what DB that is.

Nah I don't do trackdays?

U will. It's in our blood!!

Always wanted, but not on such an expensive bike. Maybe a older cheaper on.

HI thompsp,
jack sprat here can you please tell me who fabricated your baffle. Can I get one or the plans. I only do track days and I don't think I have used the bikes full potential as yet so I will not know any other (the slick pin is not in yet )
Regards jack sprat

I would like to know where to get a DB killer from that fits the BMW akro stubby exhaust. Don't mind drilling a hole to fit it in. That's if it's too loud. Ha

 

[thompsp]

HI thompsp,
jack sprat here can you please tell me who fabricated your baffle. Can I get one or the plans. I only do track days and I don't think I have used the bikes full potential as yet so I will not know any other (the slick pin is not in yet )
Regards jack sprat

Hi Jack. Thanks for the info on the rearsets.
Jack & DJUK -I got the baffle from http://www.mhpexhausts.com/exhaust/baffles.php
It was £50 and the chap fitted it (drilling through titanium is hard), with a grommet neatly blanking the hole at the back and it looks brilliant. More pics are on this thread: http://s1000rrforum.co.uk/showthrea...r-Noobs-Danmoto-Decat/page2&highlight=Thompsp
After trying 4 different settings, I have now removed the inner perforated tube completely, as the power is very good and it reads a nice 103db - performed by a professional using a professional db meter (I think it was at 5500 revs, at adistance of a meter at 45 degrees to the rear)

 

[DJUK]

Thanks thompsp. When I get my decat fitted I shall decide whether I need one. Might just purchase one anyway, for the days I have a headache. Haha

 

[Burner]

I have a full ti arrow system , it's very LOUD without the baffle. Can's about 300mm long, but i bought it cuz the system was uber light.

First time I ran it earlier last year it blew 103db at Rockingham (104db limit) and 104db at Cadwell (105db limit) with baffle. I tried it without baffle at Cadwell too and it failed miserably, something like 109/110 or so.

The standard baffle is a bit noddy.

I did a couple of loud days at Donington and took the baffle out, me old man said there was me and Gino Rea on a Moto2 bike that were the loudest out there.

I wanted to do a day at Silverstone, but there was no way it was going to pass the 105db static at 3/4 max engine speed even with baffle, nor the drive by, I can't remember the limit on that one tho' - 102db?

Just bunging the can up with more wadding and/or restricting the flow with smaller orafice is just going to stifle POWER and ruin your day....

I made a baffle from a section of perforated tube I bought off ebay for about £7. Cut a section from it, cut 2 slits in either side a few tens of mm apart, then bashed them in with a ball peen to form scoops to catch the gas. I held the tube in a vice with soft jaws and supported underneath. The intention is to capture part of each gas pulse and separate it so that part of the pulse is marginally delayed on its way to exit the can as it now has to negotiate the perforations. That way each pulse doesn't exit it one large bang.......

I drilled 2 holes top and bottom of the rear of the standard baffle and lock wired the tube to the baffle. I'm sure it rattles a bit but it's a track only bike, so I'm not too fussed. You could bolt it to the baffle but I wanted to be able to remove quickly if I needed to.

Result was blasting past the noise name on the start/finish straight all day and not a hint of the can the can being offensive. It's done a couple of days there now and I've had no problems whatsoever, and all it cost me was a couple of quid for the tube.

Tried to upload a few pics from flickr but not having any joy judging by preview post, here's one in case it works.

Ta

 

[Burner]

http://www.flickr.com/photos/102341700@N03/11877802546/

http://www.flickr.com/photos/102341700@N03/11877800456/

trying the links