Hi, I need to repack my "silencer" on my 57mm Termi race system (107dB is a bit too noisy for most Trackdays, even with my biggest smile at the noise tester!!) and have a couple of questions: To get to the inside of the box, which end is it necessary to remove? I assume it is the inlet end (closest to the engine) at the front of the box? Once I remove the rivets and take off the end cap, are the perforated "baffles" attached to this end cap and it all comes out in one go? I assume it is then just a case of wrapping the wadding around the perforated tube(s) and cramming it all back inside - I have done this before on 996 Termi's and it was ppretty simple. Last question - what size (diameter/length) are the rivets and where does one buy these from? I have seen stainless pop rivets on the Bay - any recommendations? Cheers, R
just put in some db killers! will be better then the standard pipes! passed on a 999R at assen with them easily! grtz Koen grtz Koen
Well, since nobody appears to have done this before, yesterday I got stuck in and did it myself. In summary: it's a barsted of a job! As I have done it now, I thought I'd pass on my experiences to anybody else who wants to do it. Answering my own questions first: Q: To get to the inside of the box, which end is it necessary to remove? A: BOTH ENDS! Q: I assume it is the inlet end (closest to the engine) at the front of the box? A: Nope, both ends need to be removed (see below). Q: Once I remove the rivets and take off the end cap, are the perforated "baffles" attached to this end cap and it all comes out in one go? A: The perforated baffle tubes are welded to the outlet (rear) cap. This makes life extremely difficult as the outlet end is the smaller end of the silencer. The tubes are oval where they join the exhaust outlet cap which makes them a lower height than the full diameter at the front of the silencer. Therefore, trying to pull them out from the back you find that the full circular part of the tubes is an arse to get out of the back end of the silencer. In addition, the tubes have fine mesh sleeves on them which have some kind of sound deadeneing filling. These stay inside the silencer as they are too big to come out of the back end! Once the rear cap and tubes are removed, the sleeves have to be taken out from the front end. Q: I assume it is then just a case of wrapping the wadding around the perforated tube(s) and cramming it all back inside - I have done this before on 996 Termi's and it was pretty simple. A: AAAAARGH!!! The silencer is filled with one length of fibreglass wadding - like a tape about 2inches wide. I felt like a kiddies magician pulling hankies out of my top-hat! I pulled and pulled and pulled and eventually ended up with a bin liner FULL of fibreglass tape!!! Looking at the condition of the fibreglass - it looked pretty good - hardly burnt at all and there was tons of it inside the silencer! Basically: I had wasted my time as it was fine inside but I had to take it all out to see! PUTTING IT BACK IN: I had pre-bought some exhaust blanket material like I had used on my 996. WASTE OF TIME as this is not suitable for the 749 silencer! It would have been impossible to wrap this around the tubes and then insert it from the back end, especially with the mesh sleeves that had to be inserted from the front end, once the tubes had been put back in from the back!! So, this is what I did - put the rear cap (and tubes) in from the back, slid the mesh sleeves in from the front over the tubes. This was nasty as the sleeves get caught on the rivnuts near the back where the numberplate gubbins attach. My arms are completely covered in nasty scratches as I had to guide the sleeves back in from the front to the back. The scratches are also impregnated with fibreglass so - very pleasant!! Then it was just a question of stuffing the bin-liner of fibreglass back into all the nooks and crannies of the silencer. There was a little bit of space left near the front so I filled that with the blanket stuff I had already bought. Lovely job! Q: Last question - what size (diameter/length) are the rivets and where does one buy these from? I have seen stainless pop rivets on the Bay - any recommendations? A: They are 5mm. I used ally ones in the end. Other points: - the caps are sealed with what looks like 3Bond - I resealed them the same. - wear long sleeves! - make sure the neighbours' children are not nearby as they will learn some new words!!! - Now it's all back together, it sounds pretty much the same!! A cautionary tale designed to prevent others from facing the same calamaties!! R
AARGH sorry mate wish I'd av seen this earlier,I repacked a racefit endcan I had previously and could have told you that you probably wouldn't of made any difference to the db output, well you would have, but probably not in the right direction. When we were on Ducatisti I asked this question on repacking and was told by someone on the site (cant remember who), but he worked for racefit, and he said they were packed by machine under pressure ? , so I wouldn't be able to reduce noise , all I did was alter tone (for the better).
Alloy rivits will be no good either. They melt ,believe it or not, You must use stainless and you will need an industrial rivit gun as they are very tough.
I thought that my 749s silencer was too loud about 2 years ago, so I bought some packing material from Nog on this site in preparation for repacking. I seem to recall that I only removed one end of the silencer ( could be wrong though as terrible memory) and started to pull out the packing. I too felt like I was performing a conjuring trick, the stuff just kept coming, and coming, and I filled a large bin liner to the brim with the stuff. I was very surprised to see that the packing ; apart from a small amount, seemed to be in a brand new condition. I realized I had done all this for nothing as I expected to find all the packing in a very bad condition, so I stuffed the entire original stuff back in from where it came, poking it in with a stick iirc. I don't seem to remember it made any difference to the sound, and I think I re-riveted with aluminum rivets, which 15k miles later still appear to be perfect! Only just scraped in the noise testing at Brands for an evening session!
Must be down to how you rev them then because I changed a few at the back and they melted. Didnt even last 500 miles in fact. That was on my 999R suppose that could make a difference .
I'm not 100% sure about the aluminum rivets. I remember borrowing the rivet gun from one of my mates who's a builder, and he gave me the rivets. I will have a look tomorrow.
Sounds like the same experience as me then! Wish you'd posted this before I wasted my Saturday!! I have taken my silencer into work (large shed with a Boeing 747 in it...)and left it with some colleagues who will install some lovely Monel blind rivets for me using their hydraulic rivet gun. These are designed specifically for high temperature applications so I reckon they should be fine. One of the reasons I wanted to repack the silencer was because I have been using billet ally Db killers but after my last outing at Brands they cooked the carbon shroud due to the heat sink effect of having blocks of ally in the exhaust gas...looks like I will need to continue to use these as they are the only things that bring the noise down to passable levels. Doing Brands GP on Monday so hope it will pass....
i am about to try repacking my exhaust but this does put me off. not only for the trouble but also the small improvement. at track days i now get readings of between 102 & 103 db. so i just need a reduction of about 2 db. as people suggest db killers for 749/999s aren't very good. i have thought about asking a local race fabrication shop if they could suggest a good way to reduce the noise as they make all sorts of exhausts. my main question is i remember seeing a detailed guide with photos for repacking a 999 exhaust but can't remember which forum it was on and hoped someone could offer a link to it.i did think it was probably from ducatisti .thanks if anyone can help
They must get bloody hot then! I've repacked 916 and Monster (Termi) cans using ally rivets with no problem. I'm pretty certain the originals were ally too. Stainless rivets will be a pig to remove on the next re-pack as they'll pick up on a drill. Before re-assembly I wrap the whole package in aluminium tape (Termignoni use a few wraps of paper masking tape) as it allows you to 'shape' the wadding making it easier to get it in the can, plus the aluminium gives another layer of heat insulation to the carbon if/when the wadding burns through.
Don't do it! - is my advice. There was absolutely no discernable difference in noise after I went through the hassle of repacking my 749 silencer. Any advice received from people who have standard 9*6 or other "round cylindrical" silencers is pretty useless. I have done my 996 and it was a piece of piss whereas the 749 Ti Termi box is a completely different beast. My recommendation is "plug" type dB killers - I have a set that are made of machined ally with two outlets. I stuff the hole with a bit of wire wool and then put the killers in. They bring the noise down from 107dB to around 102dB. They completely muck up the way the bike revs (big flat spot and juddering when coming out of it) but after a lap or two the wire wool gets blown out and the throttle response is ok but not 100%. Also, they get farking hot and have overheated the CFRP shroud around the box. This is why I went down the repacking route but it just didn't work! Solution: do more Donnington unsilenced days! I did one in October and it was a joy to ride the bike without the restriction of the dB killers! Cheers, R
thanks Ricky i made a set of alloy plugs which fit in the end . they are 12mm thick and i machined in 2 smaller ovals . they look quite good , but at snetterton i still just scrapped through at 101db with a bit of help from focused events who helped at the noise testing station. they told me to rev the bike but put it in gear and get the clutch to just bite. unfortunately i took the plugs out and when i got fuel latter in the day the pump man who is also the noise man kindly removed my pass sticker. the organisers were again very good and we agreed to monitor my bike on the ride by meter which i had no problem with.this is probably a ducati thing static test = very loud , ride by = glorious but a softer sound. i didn't ride with the plugs in as they were being developed and at the time had no fixing in screws. i might make a second set but make them deeper.
