Muzzy Exhaust
How much difference does the Muzzy exhaust system make?
I have just finished installing my second Muzzy system. The entire system weighs just 5 1/2 lbs on my bathroom scale. The stock mufflers alone weighed 13 1/2 lbs. I didn't weigh the headpipes and centerstand but it's a few pounds more off the bike as well. The stainless steel head pipe looks great and fits perfectly. You can search the Ninja 250 board for installation tips if you need them. Less weight + more power = faster, better-handling bike.
The Muzzy is loud, but it has a deep tone; I don't think it is obnoxious. A good helmet keeps most of the noise out. Oil filter and drain plug access is fine.
Do I have to remove the centerstand to install a Muzzy exhaust?
Understandably, most people want to keep their centerstand when they put on a Muzzy system. Centerstands are very useful.
There are a few problems with this, however. First, the spring that holds the stand in place when retracted rubs the Muzzy's larger head pipe.
Second, there is no "stop" for the stand anymore when retracted (since the left canister is gone); there is nothing to keep the spring from pulling the centerstand up into the swing arm and drivechain. You could possibly fabricate a bracket to hold it in place, but it would involve some skill and is not a standard mod, so there isn't much information about it.
Lastly, the Muzzy is designed to increase performance a bit, sound good, and look good. One way it looks good is by really cleaning up the back of the bike; with the stock exhaust cans gone the swing arm is fully visible. If you leave the centerstand on, it will be quite an eyesore.
Without meaning to discourage anyone from trying, it's probably more trouble than it's worth to keep it. You can buy a nice swingarm stand for about $70-100 though, which will let you do most of the maintenance the centerstand allows. The only time you'll probably still use the centerstand is when you're doing rear suspension work; the stand can be loosely attached temporarily with two 17mm bolts, and put back in the parts bin when the work is done.
How do I repack the Muzzy?
I repacked my Muzzy last night using the manufacturer's kit. When I opened up the can, what little fiberglass was left in it had settled to the bottom half of the can so there was no sound absorbing material at all in the top half. It's no wonder it was so loud. I estimate that there was only about 1/3 as much fiberglass material in there as there was in the replacement kit. With the new packing the bike is quite a bit quieter than it was. For my taste, it's still louder than I'd like, but it's tolerable.
The repair kit consists of the perforated inner tube wrapped in fiberglass. I ordered this directly from Muzzy last fall. If you could get the right fiberglass material from a muffler shop or auto parts store, there is no reason you couldn't just replace this bit since the metal pieces were all in good shape. To install this, just drill out the rivets and remove the end cap (sounds simple, but there was the small matter of a broken drill bit and what seemed like a lot of blood at the time...). Only one end cap needs to come off and the engine side cap is easier to get off since the mounting hardware provides something to pull on. I removed both caps because I wanted to experiment with some additional baffling at the outlet end.
You can go to muzzys.com and order the kit. It's about $25. You'll need a pop rivet tool (about $10) and rivets (1/8" diameter, ~3/8" length) to put it all back together. The end caps are stainless steel and are reused.
I poked around the web and found packing for glass pack mufflers several places for about $6. If I were to do it over, I'd just get the packing. I suspect that auto stores or motorcycle shops probably stock this kind of stuff.
I've no idea where the old packing goes. I guess it just breaks into small pieces and blows out the tail pipe. I bought the bike with the Muzzy so I don't know how long it has been on there. The bike had about 10,000 miles when I got it and it's at a little over 16,500 now, so it looks like this is something that needs to be done pretty regularly.
