cl/cb360 exhaust question

[XsjadoTwin]

I'm trying to eek out a little performance gains from my 75 cl360. Now ive creeper around on the forums a bit and tend to ask a lot of questions. But I have noticed a couple threads on here saying how a 2-1 exhaust is better performance wise than the factory 2-2.

Now I have several old guys in Tue neighborhood who love my bike and I made a deal with them. Idnlet them ride it if when I'm done if I could borrow some of their tools/skill now my neighbor has a pipe bender at home and a mandrel bender at work. I'd want to maintain as close to stock looking as possible with the high scrambler style look.
(Personally in my garage I have access to a MIG and TIG welders, as well as a plasma cutter and the 3 tool chest full of your every day needbe's, grinders, discs, files you name it when it comes to small stuff I probably have it)

My 2nd question would be, IF i would experience any sort of performance gains by making the 2-1 exhaust where would be the optimal place to make my splice where the 2 pipes meet? or is there any way for me determine the most efficient way of making a 2-1 set up?

I know this is a very niche question but I figured id ask here first rather than call and wake up me neighbor, hah.

Thanks guys(n gals?)

 

[XsjadoTwin]

Bump- anything, 80 views and not a single peep. Dont be shy guys I'm looking for a little exhaust 101 and from what ive read going 2-1 is better (Honda apparently did it in the following years if I read correctly)

Any advice guys, or anything I could be reading up on?

Thanks again,

Joe

 

[D4N63R]

If I was you I would look at every angle of a Mac 2-1 or any other decent exhaust installed on a bike and try to replicate it. They've done all the R&D already.

A 2-1 promotes scavenging a lot better then 2-2. It's same reason cars run 'X' pipes.

Edit: that's not to say a well built 2-2 can't perform. Don't need to start a big war in here. Hahaha

 

[AlphaDogChoppers]

Well, for one, I wouldn't necessarily think Mac did any R&D beyond just making their pipes fit the bike.

As far as performance gains go, whatever you do won't make enough difference to matter. Just fabricate a collector for your existing pipes, and experiment. Don't make the collector too large. The whole idea is to maintain exhaust velocity, so the collector should barely be larger than the header pipes. If the collector is too large, when the pressure wave hits it, it'll be like an open ended pipe, and the pressure wave will reflect back. (reversion) Smaller collector, means higher velocity, and the pressure wave will assist in scavenging the other cylinder.

Ideally, the headers should be the same length, but that isn't really going to happen. What length should the headers be? That is basically what you are asking. I would shorten them about as much as the length added after the collector, not including the muffler.

In the end, you are building a custom bike, so build what looks good. You aren't racing it, you are riding it.

Now, spend a little time Googling, because there is a shitload of information out there. I started to do it, using search terms like "exhaust basics," and "exhaust 101." Then I thought, "Shit, you can do your research yourself."

Do you really want performance? Any gains you get from building a custom exhaust is going to be trivial. Where you can really get some gains is on the intake side. Contact Murray Carbs and see if they do a kit for your bike. A Murray Mikuni carburetor kit will make a World of difference. They will come with tuned length intake manifolds and a pre-jetted set of carbs. This upgrade you will DEFINITELY feel a difference. (if available.)

Oops. Forgot the link. His Web site sucks, but his carb kits rock.
http://www.murrayscarbs.com/

 

[D4N63R]

Do you really want performance? Any gains you get from building a custom exhaust is going to be trivial. Where you can really get some gains is on the intake side. Contact Murray Carbs and see if they do a kit for your bike. A Murray Mikuni carburetor kit will make a World of difference. They will come with tuned length intake manifolds and a pre-jetted set of carbs. This upgrade you will DEFINITELY feel a difference. (if available.)

Oops. Forgot the link. His Web site sucks, but his carb kits rock.
http://www.murrayscarbs.com/

doesnt make kits for my bike :-[ thats it! throwing it in the garbage!

 

[AlphaDogChoppers]

Oh, well. You'll just have to make do with the stock carburetors.
These bikes don't have a lot of performance, but they are OK. If you want a faster bike, you will have to buy a faster bike.

Enjoy it for what it is. Build an exhaust system that pleases you aesthetically. Then ride the bike.

Too many guys get all hung up in customizing their bikes and forget the reason we have bikes to begin with. That is, to fuckin' ride 'em!

I am guilty of this myself.

 

[Sonreir]

http://www.dotheton.com/forum/index.php?topic=39814.msg471764#msg471764

You're welcome.

 

[XsjadoTwin]

Well, for one, I wouldn't necessarily think Mac did any R&D beyond just making their pipes fit the bike.

As far as performance gains go, whatever you do won't make enough difference to matter. Just fabricate a collector for your existing pipes, and experiment. Don't make the collector too large. The whole idea is to maintain exhaust velocity, so the collector should barely be larger than the header pipes. If the collector is too large, when the pressure wave hits it, it'll be like an open ended pipe, and the pressure wave will reflect back. (reversion) Smaller collector, means higher velocity, and the pressure wave will assist in scavenging the other cylinder.

Ideally, the headers should be the same length, but that isn't really going to happen. What length should the headers be? That is basically what you are asking. I would shorten them about as much as the length added after the collector, not including the muffler.

In the end, you are building a custom bike, so build what looks good. You aren't racing it, you are riding it.

Now, spend a little time Googling, because there is a shitload of information out there. I started to do it, using search terms like "exhaust basics," and "exhaust 101." Then I thought, "Shit, you can do your research yourself."

Do you really want performance? Any gains you get from building a custom exhaust is going to be trivial. Where you can really get some gains is on the intake side. Contact Murray Carbs and see if they do a kit for your bike. A Murray Mikuni carburetor kit will make a World of difference. They will come with tuned length intake manifolds and a pre-jetted set of carbs. This upgrade you will DEFINITELY feel a difference. (if available.)

Oops. Forgot the link. His Web site sucks, but his carb kits rock.
http://www.murrayscarbs.com/

I honestly appreciate the information, really. Sorry I didn't google before hand. I was posting mainly to confirm whether or not 2:1 was more efficient than a 2:2 on this specific motor. But the information you provided is a huge help and I will continue to do my research should I decide to change out (I won't call it an upgrade, because by the looks of it I won't be gaining much more than an audible change)

 

[crazypj]

It depends what you mean by 'more efficient'
Being a 180 twin and not a 360 twin the exhaust pulses don't tend to 'work together' very well except at very very specific rpm.
2:1 should be significantly lighter than 2:2
My modified 360's use 2:1, MAC did design work on XS650 exhaust then used same shape for 360 :
It can be made to work but won't look the way you want it.
The pipe diameters also need to be right, the larger you go for looks the less power you may make and the more fuel you will use
Loud isn't fast on 360 until exhaust length and diameter allow the harmonics to work
I'm pretty sure you cannot get max possible power with a high level pipe, there just isn't enough space to get the needed length