Mac Performance Exhaust Installation Help (PICS)

[ddaum]

1980 GS550L
25,000 mi.
stock

Hello. I'm having a bit of trouble installing the new MAC exhaust system that I bought. The system didn't come with any installation instructions and minimal hardware. I removed the old system, replaced gaskets and hardware and left the header loose while trying to hang the muffler. The problem is that the brackets supplied with the system seem inadequate to mount anywhere properly. For argumentative purposes, I managed to hang the muffler from the only place that I could find feasible; the lower shock mount. Now, this is connected to the swing arm, and in this configuration it would cause the exhaust pipe to travel up and down with the swing arm while riding. Wouldn't this put unnecessary stress on the pipe? I've been working on this for over four hours and the muffler will not twist to mount to anything including the original muffler mount, at least not with these brackets. Can someone please guide me in the right direction? Pictures would be great! Thanks!

[Chris Daniel]

I would definatly NOT ride it with the muffler connected to the swingarm. It WILL break something, most likely the exaust bolts/studs in the head..........not good.

Judgeing by the pictures it looks like you can slide the bracket back and forth on the muffler (am I correct?).

If so I would spin your bracket around 180* and try to bend it to make it fit the original mount. Another possibilty would be to make a strap of sorts that you could wrap around the muffler and then bolt to the original mount.......

Other guys would probably be a little more helpful here.

Again, I would NOT ride it at all with it connected to the swingarm........it WILL break something.

Good luck and I hope this helps.

[focus frenzy]

flip it and bend it.
or fabricate one that will fit.

[Buffalo Breath]

mac

make sure you have the muffler as far up on the collector as possible

[mixongw]

The proper placement for the muffler bracket is on the passenger foot peg bolt (inside). I had to make an extension for the bracket. It was simple, just a piece of flat stock with a hole in each end.

[ddaum]

The proper placement for the muffler bracket is on the passenger foot peg bolt (inside).

You can see in the lower right portion of the second pic that there is no passenger foot peg bolt, only a pin secured with a cotter pin. The peg mount is welded to the frame. Any other ideas?

[GARYEIN1]

MAC EXHAUST

IS YOUR SYSTEM A FOUR INTO 1 UNIT
OR IS THERE 2 MUFFLERS

MINE IS A 85 GS550L
WITH 2
GARY

[mixongw]

The proper placement for the muffler bracket is on the passenger foot peg bolt (inside).

You can see in the lower right portion of the second pic that there is no passenger foot peg bolt, only a pin secured with a cotter pin. The peg mount is welded to the frame. Any other ideas?

I guess the setup is different on my 1100GL. Sorry for the inaccurate post.

[ddaum]

IS YOUR SYSTEM A FOUR INTO 1 UNIT
OR IS THERE 2 MUFFLERS

The system is a MAC 4-1 for GS550L 1980

[JayH]

Don't ride your bike w/ the exhaust on the lower shock mount. The MAC 4-1 exhaust I had for my old Honda CB550 didn't line up exactly either.

Find a good sturdy piece of steel and make a bracket. The bracket should extent from the lower part of the passenger peg back to the mounting point that MAC provides. Just keep in mind that not only will the exahust try to move in all planes so make sure the bracket is hefty.

[ddaum]

Just so everyone knows, I haven't been riding the bike with the exhaust mounted as in the picture. I put the bracket on there only for the picture so others could see the bracket and where it might be able to reach. Thanks for all the replys, but i was hoping that someone with a 550 and a MAC 4-1 like mine could post an example picture of their muffler mount. I'll be off tomorrow to fab my own bracket to mount on the original muffler mount. I'll post a pic when I'm done. I just don't understand why MAC would advertise this system to fit my bike and provide brackets that don't work. :x
Thanks everyone!

[ddaum]

Well guys, I feel like a bit of a meathead. Although I did have to tweak the MAC bracket a little bit in the vice, I was able to make it fit to the original frame mount today. I loosened all the header bolts, and muffler clamp again. Then I slid the muffler as far up the header as it would go. After bending the bracket in the vice a bit it still took a little persuasion to get the bolt holes lined up. I guess MAC can't be perfect, but for the price I paid, they SHOULD be! Here's the pics.

[Chris Daniel]

Thats great to hear/see.

Most of that aftermarket stuff has to be "tweaked" to make it fit just right.

For example my MAC 4-1 system on my GS650 was rubbing the rear axle on the swingarm heavily. I tried every type of bending and repositioning I could possibly try and ended up having to put a rather large dent in the muffler to make it quit rubbing. Other than that it is great .

Anyway, good to see you have it fixed.

[JayH]

Good deal! It looks good.