found this in my exhaust

my bike has seemed choked up since i got it so today i decided to see if maybe Yamaha screwed up and left something loose in my exhaust (like a tampon or something). i pulled off the mufflers and blew thru them and they seemed reasonable so i checked the header. sure enough there was a big restriction. well after contemplating for a while i decided to do what the boys on myth busters would do. after contacting the bomb squad they told me they don't come to peoples houses and blow things up that only happens on TV! well on to plan two,so i hooked up my compressor and pumped it way up and then dumped the pressure into the pipe. nothing happened so i tried it again. well wouldn't you know this round thing popped out. so i tried a few more times and another round thing popped out. i was excited then but after a bunch more tries i only got the two of those round things out. i don't know what they are probably some kind of fixture to keep the pipe round when they weld it together. musta been a friday or monday pipe and they forgot to blow it out after it was done. i enclosed a picture so that if any one else thinks their bike is choked up they can blow out their pipe. there only seems to be two in there. you need a really big compressor for this and a few other special tools. if anyone is interested in specifics they can pm or e-mail me. the bike is slightly growlier and seems to rev easier. now i'm gonna hafta see if Yamaha left anything in my intake tract.



friday :yahoo: :yahoo: :yahoo:

Looks like part of a catalytic converter.

Since you posted this at ten minutes to Friday, I think it's one of your cylinder heads.

:lol:

Crap, I just noticed your hometown. Now it KNOW it's prolly all that's left of your engine after all the damn salt they dump on the roads had its way with you. I'm from Syracuse, where no car survives three winters. I'm pretty sure even FJRs don't either.

It looks like a peestun. Dam feeger threw a peestun dawn the exast. Dat can't be gud. I adviz stuffin back in pipe

I'm also considering the cat removal. Prolly next winter...

You found the factory installed rodent stoppers that keeps them from living in the exhaust chambers. Usually these rodent eliminators are referred to as Cats.

Oh, if only it was that easy...

You mean ALL the exhaust passes through these? One in each header, so there are 4 total? You have 2 remaining? Or only 2 to start with? If 2, which headers? That's disgusting, making all that wonderful exhaust gas pass through them little tiny orifices.

dcarver said:

You mean ALL the exhaust passes through these? One in each header, so there are 4 total? You have 2 remaining? Or only 2 to start with? If 2, which headers? That's disgusting, making all that wonderful exhaust gas pass through them little tiny orifices.

Click to expand...

Only two to start with. But you knew that.

Exhaust system is 4-2-1-2...4 header pipes into 2 collectors, into 1 chamber, into 2 mufflers. The cats are in chamber, located in the inlet sides of the two midpipes headed to the mufflers.



Oh, the correct word is "ORIFII"

That's the muffler bearing.

well after a day with this (about 260 miles in cold rain) not noticeably louder but a little raspier exhaust note. i like it. seems to rev better and definitely didn't lose any power. i used to have a shudder/ vibration at heavy throttle low rpm that would make me let off the throttle. that is gone now. that was unexpected and i will have to see if it is only from the weather or something. here are some more pics of the operation. i cut out a lot more than i needed to because i didn't know what was in there. should have looked it up so i would have seen the other posts on it. if someone plans on doing this themselves you want to be a fairly proficient tig welder or know one who owes you.if i do this again i would only cut the area directly over the cats on both sides.

Now to the metal scrap yard to pick up some extra cash?

Nice job - beyond my skills...

RadioHowie said:

Only two to start with. But you knew that.
Exhaust system is 4-2-1-2...4 header pipes into 2 collectors, into 1 chamber, into 2 mufflers. The cats are in chamber, located in the inlet sides of the two midpipes headed to the mufflers.

Oh, the correct word is "ORIFII"

Click to expand...

Well, why don't you shove one of them, up one of your, "ORIFII"?

:jester:

dcarver said:

Nice job - beyond my skills...

Click to expand...

Whooo ............. News Flash!!!

This from the guy who can't flush a toilet without directions :dribble:

:haha: :haha: :haha: Yer Killin' me carver

:jester:

Hey exhaust geniuses...

As has been pointed out, this exhaust is 4 - 2(briefly) then 1 - 2. Wouldn't there be a low end torque advantage to putting a divider in the big plenum that forms the "1" part when removing those nasty cat guts. So it would just be a 4 into 2 exhaust.

So long as you aren't using the O2 sensor anyway that is...

Somebody did more than that, but I can't find it. Fabricated tubing inside the cat plenum. Made a true 4 into 2, even though it looked stock from the outside.

Yeah, I think I saw it. That is another way to do what I suggested, maybe even better since the exhaust flow would be smoother down the pipe. It doesn't seem like it would add too much complexity...

But the question remains, is it worth doing?

[Edit] Found it here It was Jaxon over on the other forum.

Fred W said:

Hey exhaust geniuses...
As has been pointed out, this exhaust is 4 - 2(briefly) then 1 - 2. Wouldn't there be a low end torque advantage to putting a divider in the big plenum that forms the "1" part when removing those nasty cat guts. So it would just be a 4 into 2 exhaust.

So long as you aren't using the O2 sensor anyway that is...

Click to expand...

I've heard the opposite from people complaining about the lack of cross-over pipe on the Holeshot headers. They say that a cross-over pipe would improve low-end torque.

Does anyone know the purpose of the cross-over between the pipes for cylinders 2 and 3 on the stock header?

As for the O2 sensor, I think hope it's safe to assume that the average of 2 cylinders will be close enough to the average of all 4:

Probably, yeah. But you'll never know, now will you?

PS - neither will I because mine's disconnected.

Not shure that i'm going to do this tomorrow but the neatest solution might be to circle the cat inserts (as it looks like you can see the 4 clamp/spot welds that hold them in place) with the zip which would totally cut off both rear pipes and with carefull before/after measuring tack and then reweld each side back on. Awesome work guys on this...as long as you don't feel too guilty about the extra HC's that we'll burn over the next year. When's the next shuttle launch btw.

Cheers

-Don