Kerker 4-1 end cap/ diffusor help

[Guest]

When I got my bike it came with no end cap or diffusor.... just a big hole. You can see the baffle inside.
Does anyone have a picture of what the diffuser is supposed to look like and how it's shaped or how its fastened into the tailpipe?
I am going to make my own a
nd just wondering about the design.
any help would be appreciated
.

[koolaid_kid]

As it happens, I have my diffuser out for repacking, so here you are. Please note, this is a 1985 kerker for an off-brand bike.

Endcap on the bench:


Endcap installed on the pipe but not bolted in:


Another shot of the endcap and muffler. You should be able to see the Kerker name:


First shot of the diffuser:


Another shot of the diffuser:


I tried to get an end shot of the diffuser, but the camera batteries chose to die at that time. Basically it is straight through, no power robbing baffles. It is throaty, but not annoying.

[koolaid_kid]

Actually, when I have my end cap off the use my wideband, I use a tuna can. Almost the perfect diameter, honest.

[loud et]

Hey kool aid thanks for all the effort with the pictures..... I should have posted my own first, I don't really have a muffler type canister, but rather a megaphone.
I think the tip of the baffle sticking out near the end is just the finish look and that's it.
I have a vance and , hines that has some kind of plate at the end, but on this 1 that might be the finished product.

[koolaid_kid]

Yes, a megaphone is a totally different animal. I have always thought they look unfinished, and their main goal is to be much louder. Hence the title of megaphone. They are always open at the end, at least the ones I have seen.

[loud et]

So I did the #4 steel wool wrap of the baffle and added a few ss zip ties and put the baffle back in. Its still pretty darn loud, I dont know if a few exta layers of steel wool will muffle it down a bit more. I know its much more reasonable than it was with nothing in there!
At least I got the bike running, and fairly smooth too for a first firing on a rebuild of the engine and carbs.
I will get it on the road and work out the bugs before I worry about the exaust too much more.

[koolaid_kid]

Yes, congrats are in order.
They do make special muffler baffle packing, which may reduce the sound volume by a few extra dB. However, being a megaphone, it will always be quite loud. Just the nature of the beast.

[loud et]

Yes, Old School, RUNNING!
A little choke and it fired nicely.
so far no leaks or catastrophies!
Plenty of bugs to work out, and I will get to my rebuild update soon I hope to post my progress.
And KK, I am CHEAP CHEAP! lol I probably will do a proper and professional baffle wrap if I decide to keep this exhaust. I am not against a loud bike. An 1100 has a nice growl to it, thats for sure.

[koolaid_kid]

You don't have to tell me about cheap. My muffler packing is a fiberglass roll I bought at Ace Hardware. Works fine for my muffler; the only reason I am repacking it is I blew it out when I removed the cap and installed my wideband for tuning. Has lasted fine AFA I am concerned. Dropped my noise level by 10dB (by half) measured with a sound meter.

[cableguy]

I've tried a few different packs in my VH megaphone, and settled on the fiberglass (or whatever it is) wrap for motocross bikes from the local dealer. $12 for 2 pieces that are the right size for the baffle. I also tried woodstove pipe rope wrapped tight around the baffle, didn't really make it much quieter just took the sharp edge off a little. Tried no packing and that's too loud for the neighbors (sorry neighbors!). 2 sheets of MX packing wired firmly is authoritative without being offensive. I would love to find a good canister style, as I do prefer those tones over the megaphones.

[cableguy]

I read somewhere that if you wrap the baffle tightly with lots of layers you'll have the most sound reduction. I first thought that looser would absorb the sound more, but when I tried it, more layers more tightly wrapped is the answer. Wire is the key for even distribution. I just used regular mechanics wire, figuring it doesn't matter what gives out first I'll just replace everything when it does.

[loud et]

Well, I have what it came with, so I will make the most of it. Its a great thing to hear the bike running at all , after so much anticipation and effort. I will mess with the baffling if/ when I feel the need after she is on the road. Its a good GS day! Here is a poor quality video just after I packed it.

[oldpara]

Does this help ?