Mac 4-2 Exhaust System

Posted: Tue Feb 23, 2010 11:37 am

Hi, Anyone using Mac 4-2 model: 001-2609 exhaust system? Would like some feedback on this sort of system please.

cheers
Frank

Posted: Tue Feb 23, 2010 10:54 pm

Hey Frank, Yeah i put a set of those pipes on my bike over the weekend. Here's the good , great look and style really complements the look of the bike . the dual pipes kick up a little higher and stop a little shorter in the back, the exhuast port is twice as big as the stock not only looks cool but gives a great sound. For me not to loud. The sound is, if you can imagine ,listening to a four into one times two . after all it is a dual megaphone.The chrome is good . I didnt have to rejet and performance and power seemed the same . Now the bad . Hard to fit together . the inside header pipes didnt go easily into the muffler . I had to flare the ends of the inlet on them , to slide the header into the muffler .Where as the outside where a little loose.The weld on the seams left something to be desired. a little rough for such a nice design. I hoped that helped . If you have any other questiond just pm me Wink

Posted: Tue Feb 23, 2010 11:15 pm

cycleboy1200cc wrote:

Hey Frank, Yeah i put a set of those pipes on my bike over the weekend. Here's the good , great look and style really complements the look of the bike . the dual pipes kick up a little higher and stop a little shorter in the back, the exhuast port is twice as big as the stock not only looks cool but gives a great sound. For me not to loud. The sound is, if you can imagine ,listening to a four into one times two . after all it is a dual megaphone.The chrome is good . I didnt have to rejet and performance and power seemed the same . Now the bad . Hard to fit together . the inside header pipes didnt go easily into the muffler . I had to flare the ends of the inlet on them , to slide the header into the muffler .Where as the outside where a little loose.The weld on the seams left something to be desired. a little rough for such a nice design. I hoped that helped . If you have any other questiond just pm me Wink

Hi Doug, thanks for the feedback. Any chance of posting up some photos?

Cheers
Frank

Posted: Wed Feb 24, 2010 1:14 am

Hey Frank I'll borrow a camera and take some pics tomorrow. If you don't mind posting them for me I'll email the pics to you . I hav'nt figured out how to post pics yet .This will give me an excuse to shows off my bike Laughing

Posted: Wed Feb 24, 2010 1:23 am

cycleboy1200cc wrote:

Hey Frank I'll borrow a camera and take some pics tomorrow. If you don't mind posting them for me I'll email the pics to you . I hav'nt figured out how to post pics yet .This will give me an excuse to shows off my bike Laughing

No worries. Just send photos to frankie.chan@ibikes.com.au

Posted: Wed Feb 24, 2010 3:14 am

Great , I'll borrow the camera from work and take the pics at lunch. And then when the boss isn't around I'll send them . I think you'll like the way the pipes look .I wanted that dual pipe look. To me it looks more balanced. And that sound , man they sound good Very Happy

Posted: Wed Feb 24, 2010 3:32 am

cycleboy1200cc wrote:

Great , I'll borrow the camera from work and take the pics at lunch. And then when the boss isn't around I'll send them . I think you'll like the way the pipes look .I wanted that dual pipe look. To me it looks more balanced. And that sound , man they sound good Very Happy

i can't wait to see your bike. And yes I'm with you regarding the dual exhuast pipe and totally agreed.

cheers
Frank

Posted: Wed Feb 24, 2010 2:07 pm

Hey Frank, I just got to work . Its 8 am here. At lunch i will take pics and send them. Cheers. Gotta get back to work before the boss walks in on me.

Posted: Wed Feb 24, 2010 2:13 pm

cycleboy1200cc wrote:

Hey Frank, I just got to work . Its 8 am here. At lunch i will take pics and send them. Cheers. Gotta get back to work before the boss walks in on me.

Once I received the photo I'll post it up for you. It 1am here Sydney, Australia.

Posted: Wed Feb 24, 2010 8:07 pm

I sent the pics to your email Frank , This is what the pipes look like Very Happy

Posted: Wed Feb 24, 2010 11:04 pm

cycleboy1200cc wrote:

This is what the pipes look like Very Happy

Doug's CB1100F fitted with Mac Exhaust System.

Nice exhaust Doug Wink

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Posted: Wed Feb 24, 2010 11:11 pm

Not bad looking at all lots of room when changing oil fillter

Posted: Wed Feb 24, 2010 11:56 pm

Hey Frank , did you get the pics I sent from my computer email or just these two from my I phone?

Posted: Thu Feb 25, 2010 1:31 am

More pictures of Doug's CB1100F with Mac exhaust system.

Posted: Fri Feb 26, 2010 3:00 am

Frank, I have to revise what I told you about no performance change with these pipes .Evidently i didn't ride long enough for the engine to get to a more normal operating temp the other nite after getting my pipes on . The engine is more cold natured with these pipes for some reason , and with the cold temps I have to ride several miles to warm it up . Anyway tonight after the engine was good and hot I definitely noticed the bike pull harder in the upper rpm range like from about 4k on up . The power band before was more leanier across the rpm range. In other words It was like it pulled the same from low to the higher rpms . When I first noticed the faster rpms I though my clutch was slipping that's how much of a change there is.

Posted: Tue Dec 11, 2012 12:15 pm

Hi Guys,

BTW, good looking bike you have there.

Do you guys happen to have pictures from the left muffler? I would like to see how the center stand fits into the picture when it is in folded-away position.

I'm planning to buy this exhaust for my CB750F -81. So far Marving 4-2 system has been a disappointment since it requires modifications to center stand or the muffler to fit properly.

Thanks in advance!

-Metu71-

Posted: Tue Dec 11, 2012 11:19 pm

The entire problem with MAC and why they should be avoided at all costs is the way they form the flange on the end at the head.

It is simply upset metal and "rings off" quickly. You get an exhaust leak and think you can fix it by further tightening the nuts which then twists off the studs.

A good pipe has the flange made by another piece of metal installed on the main pipe and welded thus being a lot thicker.