Single or Dual Crossover?

[BMWzenRider]

Ok, 'nother question for the group to ponder, opinionate, and argue over... ;)

I have a 1982 R100RT with a Dual Crossover header that is in pretty sad shape. The previous owner used two rear crossover pipes on it, making the front too short to reach, so he just angled things in and goobered up [pinched, bent] the stubs on the headers and managed to tear off the bolt bosses from the crossover. Plus, there is not enough room now to get the oil filter cover off from the header being angled in, they are rusty, etc...

My Questions:
Does it make a difference in performance, mileage, smoothness, idle, noise, etc... if I use a Single vs. a Dual crossover header when I replace it?

What is the best exhaust nut wrench to use? Is Ed Korn's wrench nice? Do you really need to be able to put a torque wrench on it, which his seems to be the only one that is capable of doing?

What about going with Stainless pipes [and maybe mufflers]? How much is Stainless going to cost, who has the best deal? Do aftermarket stainless mufflers sound stock? [I hate loud bikes...]

There! That aught to give you all something to chew on for a little while.... ;)

[The_Veg]

I cannot answer most of your questions, but I can tell you some things about exhaust nuts. First, when removing them be VERY careful. If you encounter high resistance, stop right there and cut them off. A Rotary tool or hacksaw is all you need- cut through JUST until you get to the threads then use a cold chisel to open the cut and remove the nut. The reason for this is that the threads can be galled or otherwise damaged very easily and repairing this is WAY more expensive than a replacement set of nuts (which are fairly cheep). To prevent future problems, use plenty of anti-sieze paste on the threads when reassembling and don't use gorilla-force torque.

For more details from a true pro, read this. (http://w6rec.com/duane/bmw/exhaust/index.htm)

[bikerfish1100]

earlier R bikes had one x-over only (70's were in front of the engine, /2s back by trans), so I suspect that one x-over is probably fine, if that's your only option. with that said- those pipes are freakin' ugly rusty nasty- get rid of 'em. EPPCO makes nice replacement pipes, as does BUB. maybe Bob's BMW as a source, or Blue Moon.
Bob's sells a decent inexpensive (about $30) exhaust wrench. to analyze the quality- the more teeth on it, generally the better it is. there were some floating around a few years ago that looked pretty hillbilly- very few teeth- you don't want one of those.
in 10 + years of airhead ownership, i've never used a torque wrench on an exh collar. anti-seize is critical for re-assembly.

[TZOLK]

Ouch!! That picture hurts the eyes!

[lkchris]

Two crossovers are better than one.

Of course if you're really interested in saving money by purchasing fewer parts, you could install a 2->1 system and really screw up your performance.

Whatever you do, put the system together using antiseize not only on the head threads but also at every pipe connection.