Harley Pipes on a 78 GS550?

[liv2wrshp]

I want to put stock Harley pipes on my 1978 GS550. Is this a simple job or am I going to have to weld and cut? I did a search and could only find people who did this on a 400 and a 1000. Thanks for all the help.

[Tarbash 27]

stock exhaust is 10 times better than harley exhaust.

[bradleymaynar]

The only thing I've ever heard of being done was to use HD mufflers on 4:1 headers. I'd think if you were going the route of a loud exhaust, you'd be better to find aftermarket pipes. Otherwise you're going to have a lot of bending and welding ahead of you. Not to mention the nightmare of getting the carbs dialed in.

Brad tt

[Tarbash 27]

harley mufflers are really quiet, not loud at all

[ruddy]

I installed a pair of H-D DynaGlide shorties on my wife's Kawasaki 440 LTD and a pair of Softail mufflers on my 850G.

Turned out that they were a perfect slip fit on the Kawasaki pipes (on Suzuki pipes, too), but there wasn't enough pipe left after cutting off the original mufflers to slide them on far enough for clamps. The crossover pipe stubs were too close to the end, so I ended up welding the mufflers on (I had to do this on my GS850 also.). Worked out well. I used 4" Stanley straps (hinge section at the hardware store) for the rear hangers after enlarging the end holes. In addition I used two 5/16 X 1" long carriage bolts with nuts and washers. The mounting provision on these mufflers allows a lot of leeway for adapting to different bikes. Total cost was $5.61, since the mufflers were free. That doesn't include the six or seven hours of work, of course. I was able to line up two of the muffler mounting holes with two of the mounting holes on my 850, however.

The overall exhaust system ended up being about 1 1/2" shorter than the originals (these were shorties), but it looks great. Since the mufflers themselves are so slim, the bike almost looks like it's running drag pipes. By the way, I did not remove the baffles. The mufflers are stock. If you get the longer H-D mufflers, they will work just as well as these did. All of them are for the same basic Harley engine, so it doesn't really matter which ones you end up with. The longer Softail mufflers on my 850 worked out great, too.

On the road the pipes sound different than the originals, but they do have a nice tone. When you really wind up the revs, they produce a sharper note, similar to a typical sports car exhaust. At cruising speeds, they're quite mellow, so you won't need ear plugs. The engine seems to rev quicker than before, and I did not have to rejet.

I say: Go for it! (Especially if you can get them from a Harley dealer for free like I did!)

[nichols750]

i am going to do this, i just got a pair of harley muffs off of ebay for $10 plus shipping, everyone who owns a harley is selling stock stuff on ebay. you can get them for dirt cheap. i tried my local harley dealer and they were jerks about their take-offs. said only our customers can have the takeoffs or else we destroy them, we never resell them!!?!? idiots.

[Tarbash 27]

I tried a pair on my gs750 and they didnt make a difference and i think they sounded bad. so i made my own mufflers and i love it.

[liv2wrshp]

How'd you make your own?

[Tarbash 27]

well its more of a exhaust tip with a reducer inside. i cut stock mufflers off right before it started to become a cone. so i had open pipes that anded near foot pegs. took piece of fence pipe, cut it about 8 inches long and slash cut the ends. welded in a washer with a smaller hole so i had backpressure and it wasnt rediculously loud. and painted it. its alot louder than stock but no where near harley loud. its just the right tone i was looking for. click on my picture and you can get a better look at what i made.

[Jason Adam]

well its more of a exhaust tip with a reducer inside. i cut stock mufflers off right before it started to become a cone. so i had open pipes that anded near foot pegs. took piece of fence pipe, cut it about 8 inches long and slash cut the ends. welded in a washer with a smaller hole so i had backpressure and it wasnt rediculously loud. and painted it. its alot louder than stock but no where near harley loud. its just the right tone i was looking for. click on my picture and you can get a better look at what i made.

Did you have to rejet? How is perfomance, and how many miles have you put on since you did this? This is exactaly what I wanted to do, and everyone said it would screw everything up...

[liv2wrshp]

So, if I put stock harley pipes on mine, do I have to rejet or anything?

[satchmo]

You will have to change some stuff as airflow, jetting, etc. will be completely different. Harley pipes are designed for Harley engines, not Suzuki ones.

[liv2wrshp]

So, in your estimation, if I just put these on my bike, it will run worse? I don't know much about mechanics at all and don't want to make my bike worse. My pipes are just rusted out and have a blow hole in the side of one.

[satchmo]

So, in your estimation, if I just put these on my bike, it will run worse? I don't know much about mechanics at all and don't want to make my bike worse. My pipes are just rusted out and have a blow hole in the side of one.

It sounds like your pipes are in rough shape, so I'm not sure how well your bike is running now :-)

But yes, putting new pipes on, that are not stock, without rejetting and or changing the airflow will most likely make your bike run worse.

[liv2wrshp]

Is it hard to change the airflow? How do I guage that?