Upswept aftermarket mufflers

[Petrus Rocks]

I am building a Cal II into a cafe racer.  I am looking for a pair of mufflers.  It is hard to find mufflers that are upswept without paying $6-700.  I'm looking for a reverse cone, some noise, finish is not critical.  I can get them ceramic coated.  Emgos are OK but they are straight.  Not interested in the Lafranconis with the seam.  Used Contis if upswept, etc.
I've seen angled adaptors but they are smaller than 1 3/4" dia.
I have seen Cone Engineering but they would need adaptors too.
 Anyone have any ideas or old mufflers?

[NC Steve]

I had a chromed pair of these Bubs that might have worked for your purposes, but I gave them to a friend last year for use in his own project.  :(  Bubs are out there and can be found, that might be a good place to start looking for a set

[Perazzimx14]

I am building a Cal II into a cafe racer.  I am looking for a pair of mufflers.  It is hard to find mufflers that are upswept without paying $6-700.  I'm looking for a reverse cone, some noise, finish is not critical.  I can get them ceramic coated.  Emgos are OK but they are straight.  Not interested in the Lafranconis with the seam.  Used Contis if upswept, etc.
I've seen angled adaptors but they are smaller than 1 3/4" dia.
I have seen Cone Engineering but they would need adaptors too.
 Anyone have any ideas or old mufflers?

A custom upswept crossover is easy to or have fabricated. Then you could use straight mufflers. 1-1/2" sanitary SS tubing and tees worked out really nice on my 850T.

[Petrus Rocks]

NC Steve-Ill look for them.  Your picture is what I'm looking for.
Perazzi-I may go that route.  I was hoping something would show up already upswept.  My pipes are fine past the crossover, just need mufflers.

[Chuck in Indiana]

Speaking of crossovers.. ;D just how necessary are they on a Guzzi? Rosie has two, ferheavinsake. I read on another list that they would make little or no difference.. I would think that Guzzi wouldn't have spent the money to put them on if they weren't of value..

[Petrus Rocks]

Good question- I understand it helps scavenging.  many other manufacturers use them- don't have them on my Triumph T140

http://bettyparts.com/images/mcm138upsw_1.JPG  this is what I'm looking for.

[Triple Jim]

Speaking of crossovers.. ;D just how necessary are they on a Guzzi?

When I used an online header design calculator and plugged in the numbers from my Mille, it spit out head pipes almost exactly like the stock pipes it has, measured from the head to the actual crossover tube.  That makes me believe that when the exhaust pulse gets to that point and has two paths to take, it returns a negative pressure scavenge pulse to the cylinder that created the positive pressure pulse, increasing peak HP.  Without the crossover tube, the pulse would originate farther down the pipe, either in the muffler if it has a substantially larger ID than the head pipe, or at the exit of the muffler.  This would make the system tune at a lower RPM.  Worse than that, the muffler itself may diffuse the pulse to the point where it doesn't have much left.

Another effect of the crossover is to cause twice as many smaller pulses to come out each muffler than there would otherwise be, which is well known to reduce noise without adding restriction.

[Petrus Rocks]

Good info Triple J!  I understand some Guzzis have a silencer in he crossover as well.

[mgfan]

Set of upswept mufflers on fleabay right now. $199.   :BEER: