the "core" is broken off of the inlet piece. If it's not connected or lined up exactly will it still function enough to ride
Hi..1st post here. I just bought a KX500 ice racing motorbike. I was not totally impressed with the power at 1st, though it was certainly entertaining enough. I noted on my 3rd day on the ice that the core of the silencer was broken off at the end cap and moving about inside-just like yours. None the less, I took it out to the ice the following day where i was rewarded with an even slower bike....and getting slower with each lap....to the point where it would not rev out or even wheelie. examination showed a large piece of muffler packing occluding the end of the pipe. I removed this and went back out-bike seemd healtheir but not all that impressive until it "coughed out" a big wad of packing at which point it became faster than it had ever been before-much more of a 2 stroke hard edge and more over rev ythan previously. further inpection reveleled not a spec of packing left in the silncer, hardly a optimal set up but still quite a bit better than it had been power wise.
So...i took it apart and found that the core had been loose inside the silncer long enough that about 2 inches of it had been battered off while vibrating against the stubb of core left on the end cap-so in fact i doubt the core was ever lined up with the end of the stinger very well while I was riding the thing. subjectively I would say that not having the core lined up in there is probably not great for power.
what did i do? my silncer looks similar to yours, a Procircuit. as i mentioned the core being so short it wasnt possible to just weld the thing back on as it would be floating on the one end and no doubt resiult in further problems...so i bought some copper plumbing pipe (about 4 inchs) which fit pretty tightly over the stub of core and also fit tightly into the channel around the ouside of the stub-in your piture I don't really see such a channel, but anyway, I jb welded that together even though it friction fit quite tightly. then I drilled a few holes i n the copper pipe and measured how long the core would have to be to fit tightly in the stinger end of the silencer-essentially making up for the missing 2 inchs of core. stuck the core into my copper pipe leaving the two inch gap , I then drilled through my holes in the copper pipe to make the holes in the core big enough to except pop rivets and popriveted the core into the copper extention. all pop riveted tight and the core fitting tightly between the to ends of the silencer I feel like the glue was probably overkill.
result- bike is even FASTER now!
would it have been more pragmatic to pay 100 bucks for a new silncer? probably, but i wanted to ride the next day, and my brief examination of dennis kirk suggests procircuit is only making spark arrester versions of thier KX500 silencer and also with a tuned down end pipe. since the bike was set up by Erik Gore originally, I hate to mess with that set up even a little...hopefully the little pop rivet stubs wont cause turbulance and loss of power...nor will any black cats cross my path...
anyway, if you leave the core loose inside the silencer body, you will probably be rewarded with less power and also blown out packing eventually. also, if you run it like that chronically, the core pipe will probably be beating the crap out of things inside and you may end up like me with nowhere to weld the core back on.
