You Know Your MAC's have no Baffel Material When.....

[Night Vision]

depends how often you like to pack.... ceramic wool will last lots longer than stainless

[YellowJacket!]

Got some performance Fiberglass wool packing today for a few bucks at the local bike shop.  Patched a couple holes on the MACS that were previously undiscovered - rear pipe.  Sanded the rusty spots and painted them with high gloss header pipe black and they look almost brand new except for one small paint run that I'll sand out and spray again.  Got all new bolts too as the old ones were pretty cruddy so it looks almost like a new system. ;D

Will wait until exams are over then finish the job.

David

[Walt_M.]

Hmmm, ceramic wool used to insulate kilns? Wonder what rpm those kilns turn and how many pressure pulses per second they damp? I think SS wool will last longer in a motorcycle exhaust. My 2 cents.

[YellowJacket!]

Well, i got impatient and it was too hot without any AC so I went out to the garage where it was coooler and finished the job.  MAC's sound a lot better!  Still have the bark but not as much bite.  Overall the pait looks great and everything looks much better than before.  I still have a leak at the junction between the y pipe and the rear muffler so I'll have to work on that a bit. 
Wrenching is out of comission for a bit because my hand sipped while I was tightening one of the bolts and I slammed my pinkey into the frame.  Looks like a dog leg and is swollen but I don't think its broken.  Its about as big as my thumb now though.
I'm going to have to figure out a way to tighten up the rear muffler though as there is nt much room to work with the center stand and swingarm and I can't tighten down that bolt enough.  I used exhaust pipe sealer putty too.

My AC unit in my house was replaced today too.  Just now starting to cool down to the 80's inside.  ;D

David

[Lucky]

both the side & center stand come off easily, pick one :D

[YellowJacket!]

both the side & center stand come off easily, pick one :D

Ahhhhh Master Grasshopper...I didn't think of that!

You know if I do that I'm gonna have to put that 83 monoshock on and then I'll be painting my swingarm......

David

[Night Vision]

Hmmm, ceramic wool used to insulate kilns? Wonder what rpm those kilns turn and how many pressure pulses per second they damp? I think SS wool will last longer in a motorcycle exhaust. My 2 cents.

for the sake of all the poor stainless sheep.... consider this:

*"ceramic wool is an industrial insulation for hi-temp applications such as turbocharger blankets on large gas compressors (2000+ HP). It is also used to wrap steel pipe prior to stress-relieving weld joints. It is a "Refractory Ceramic Fiber product" made from "Crystalline silica formed at over 1800 deg. F''

* according to the manufacturer

[Brian Moffet]

A long time ago, some might say a lifetime ago, I used to build heat-treating pads.  These were nichrome braided wire core, a series of ceramic beads, and then a nichrome braid on the outside.  The beads made the ropes somewhat flexible. These were attached to high-current systems and would heat metal up to just below the point where you would lose elasticity.  The pieces would be welded together, and the cooled off in a very controlled a slow manner.  This was to prevent crystallization in the metal. 

We also built pads out of these, which were a cabled looped and attached to a ceramic mat.  These could be wrapped around something small and used to heat treat the piece.  I think they held up normally  up to about 1500 degrees F or so at the core.  Most of the time they were not run that hot.  The ceramic pad had no problems dealing with that at all.

However, I suspect that the airflow through the pad would be different than the airflow through stainless.  Might make a difference in jetting.

Brian

[YellowJacket!]

OK, this is one of those WTF?? moments.  A while back I posted that there was a big difference in the pressure coming out of my MAC's and that the pressure from the rear was significantly stronger than that of the front.  Well, today I found out why.

Feeling a little better and suffering from major cabin fever, I decided to try to finish  the job on YJ. I had painted the pipes and mufflers a couple days before I got sick, so they had plenty time to cure.  I stuffed the baffels with packing material and started the bike up.  Great pressure from the rear pipe but almost nil from the front.  Started thinking bad valves, lost compression etc...but the front headers were getting hot.

So, in a moment of genious, I decided to stick a pvc pipe up the front pipes baffel and it stopped dead! DOH!  It was blocked!  Did not notice it after I took the baffels out and did not even think of looking through it but apparently there was a wad of the old baffel material or some sort of wadding vulcanized inside the pipe.  Knocked it loose and lo and behold could see right through my baffel.  That crap had been stuck in there since I got them and I never noticed it.

So, I gently repacked the baffel, slid it back in the can and bolted it back in place and fired YJ up and WHAM!! THATS how a V-Twin should sound!!  I can now put my hand over both exhaust ports and feel the gas smacking my hand equally.

Now I just have to get over this chest crap so I can get out and ride and feel the difference without coughing a bunch of snot all over my visor.

The only question is how the heck did it get in there and get lodged the way it did?  COuld it have been something someone stuck up in there as a prank some time ago to the person who owned the MAC's before me?  It was a ball of compacted fiberglass and a little aluminum foil and it was stuck pretty tight.  Exhaust was able to still flow through the vents in the baffel but not straight down the tube like they are supposed to.

NOW, this is gonna be a fun ride!

David

[h2olawyer]

You might want to check your mixture & synch after removing that obstruction.  Could have been having adverse effects at the intake end of things.

Thought I felt the ground shake a while ago.   ;D

Glad you're starting to feel better.

H₂O

[67GTO]

I'm surprised the bike did not overheat!

[YellowJacket!]

I'm surprised the bike did not overheat!

Everything surprises me about this bike!

Rode the Dragon with 1/4 fork oil in one fork and almost none in the other.
Rode the bike for several months with my jets reversed.
YJ likes to run. She has Soul!  ;D

As far as overheating, she does run on the warm side.  I have a digital temp readout and it is usually above 210 after riding for a while or sitting at stoplights.  Cools down below 200 while cruising.

Even Lucky was "baffled" by the exhaust pressure difference a couple weeks ago.

David

[QBS]

H2Os' counsel exhibits wisdom.

[YellowJacket!]

H2Os' counsel exhibits wisdom.

Good point.

Last time Lucky and I tinkered with it was before I had taken the baffles out.

Thanks. ;D

David

[Tiger]

The only question is how the heck did it get in there and get lodged the way it did?  Could it have been something someone stuck up in there as a prank some time ago to the person who owned the MAC's before me?  It was a ball of compacted fiberglass and a little aluminum foil and it was stuck pretty tight.

;) Just maybe...Lucky was slowing the competition down a bit, eh  :o LOL ;D :D :D :D :D :D :D :D :D... ;)

                   8).......TIGER....... 8)

[h2olawyer]

H2Os' counsel exhibits wisdom.

Good point.

Last time Lucky and I tinkered with it was before I had taken the baffles out.

Thanks. ;D

David

Funny, but it was my initial thought after reading your post about the 'plugged' baffle.

Not really wisdom, QBS, just an abnormally lucid moment.   :D

H₂O

[YellowJacket!]

The only question is how the heck did it get in there and get lodged the way it did?  Could it have been something someone stuck up in there as a prank some time ago to the person who owned the MAC's before me?  It was a ball of compacted fiberglass and a little aluminum foil and it was stuck pretty tight.

;) Just maybe...Lucky was slowing the competition down a bit, eh  :o LOL ;D :D :D :D :D :D :D :D :D... ;)

                   8).......TIGER....... 8)

heh heh heh....

I've been thinking about that for a long time.  Only answer I can get from lucky is a crooked smile.  ;D

David

[YellowJacket!]

Forgot to mention....OH MAN DOES IT SOUND GOOD!!!!

;D  ;D

David

[h2olawyer]

They must be working right since you now have to yell!   ;D

H₂O

[YellowJacket!]

LOL  ;D H2O

Kinda makes me think of Lucky's dirt dauber in the carb.  Not something that you would usually think of being there but it was.  I almost think mine was deliberate.  Looking at the baffle, there is no way that it could have gotten around the flange and back into the baffle tube.  It was wadded up into a ball and stuffed up in there.  Since it was about 3/4 the way up, the exhaust was flowing in the tube then out the vents to go around the obstruction then back in the vents in front of the obstruction and back out the tube.

My cold is almost better. Not coughing as much today but the sinus pressure is horrible and the antibiotics have wiped out any remnants of normal intestinal flora that I had....sorry tmi.  More importantly, the sinuses have cleared enough that my equilibrium is back on track and I'm in better shape to go for a short ride.  Have to go to the postoffice tomorrow and its only a mile away so YJ will be on the road again.

Oh, and I sold enough old textbooks to pay for this semesesters books as well as a new windscreen.  ;D

David