What to use for loud exhaust?

Hi chaps,

I have taken the beast for a longer ride last week and glad to report it goes well, apart from the hesitancy at low end, which I will be addressing with help from you under another thread.

However, even though the custom exhaust is killer, it is just a tad too loud for (my neighbours) comfort.

I got some baffles to drop in but they make hardly a difference by themselves, so I think I need to wrap these and then re-insert them. If you google/Amazon/Ebay 'exhaust packing' all you get is fibreglass wadding. ... not that keen tbh.

So I'd rather use (medium) steel wool for this, but I read this is highly flammable?

What is everyone else using (if anything beyond stock) and is fibreglass OK, or steel wool?





Paul

Paul,

I have tried a few things including steel wool, which does not work well or last long and gets blown to one end of the baffle quite quickly.................then impressive sparks fly !!

The White Baffle Wadding as sold on Ebay is the best I have found, but wrap it tightly around baffle and use wire to keep it in place.

There are some good videos on YouTube showing how its done which are informative and good.

Pete F
UK

I don't know much about it, so I cant help
but.... the bike look amazing!!!

Look up "Acousta-fil" on Ebay, it's sold in sheets & expands to fill voids when heated by the exhaust. And because it's made of long strand fibreglass it's less prone to blow out.
Or you could try this type that forces the sound through a set of baffles thereby muffling it, I have a pair for my MT-01 when MOT day comes round, they do a fair job of muffling. They do various diameters & lengths, I would've thought this shortest one would be enough to take the edge off the noise. Although you'll need 6 of them which won't be cheap Edit: Unable to post Ebay link, look up item no. 151293112591

I had a 1974 KX125 that I raced and from the factory, the exhaust was 120 db. We couldn't race at the tracks in Ontario until we got the db's down to 110db. I ended up wrapping the baffle with fiberglass matt which is a long strand random laid and comes in a variety of thicknesses. 1/8" or 1/4" works well. Wrap it around the baffle fairly tight and try to wrap enough on so that it will fill the inside of your exhaust pipe. Once wrapped around the baffle, wire tie it to the baffle with stainless locking wire. Wrap the wire in a spiral wrap end to end and then cross wrap it on the way back. (Similar to the way a spool of string is wrapped) You only need the wire to create a diamond pattern with the diamonds about 1" long.
This worked for me and brought the db's down to 107 as I remember it. The inspector's at the track were happy.
Best place to get it would be a fiberglass lay up shop, like a boat builder (price wise).

I should have asked for a pic of the baffles you picked up and plan on wrapping. Depending on the design of the baffle, it may not perform as you might hope for depending on how the exhaust acoustics can reverberate on the baffling material. A pic would help here. Thanks
KB

Phil wrote: Look up "Acousta-fil" on Ebay, it's sold in sheets & expands to fill voids when heated by the exhaust. And because it's made of long strand fibreglass it's less prone to blow out.
Or you could try this type that forces the sound through a set of baffles thereby muffling it, I have a pair for my MT-01 when MOT day comes round, they do a fair job of muffling. They do various diameters & lengths, I would've thought this shortest one would be enough to take the edge off the noise. Although you'll need 6 of them which won't be cheap Edit: Unable to post Ebay link, look up item no. 151293112591

I had those for my 1976 Harley sportster XLCH which had thru pipes and I also had them just for the MOT as I found they restricted performance a great deal.

I have found these - £26 for six.



They are 14cm long and on their own don't do much as there are just holes, no baffles, so they need wrapping. The rear bit can be adjusted to restrict it even more, but I'll leave it on the longest setting for now to let as much air though as possible.

I just wonder if performance will suffer ... and if it does, will I notice it??

I will go for the fibreglass option with steel zip ties and post pics and vids of the result - next week probably. Ill also need to drill holes for the retaining screws, and for that the rear wheel has to come out. I have to leave the pipes on as the three sections (down pipe, collector section, rear pipes) are apparently glued together...

Thanks for the advice all!

Paul