After Market Exhaust questions

[firstGSrider]

Hey everyone.
I just recently purchased my first GS which is also my first bike. I am looking forward to working on it over the winter and have some questions regarding replacement of the exhaust. The pipes are rusting thru on the bike and I'd like to put a whole new system on it. Now I found a 4-2 from MAC but they claim it fits up to 1980. And I found Vance and Hines 4-1 Megaphone system. Will I have trouble putting this on my bike? I can't seem to find one that includes 1981 but I don't think there is really any difference.
I want to replace the exhaust clamps on it and just curious if I need to purchase these seperate or if they usually come with a new exhaust? And will I need exhaust gaskets as well? Which will offer a better sound and performance 4-1 or 4-2? I plan on putting pods on to replace the airbox as well. Possibly a Dynojet stage 3. Any suggestions would be great.

[MisterCinders]

What bike?

If you change to pods and that pipe, you will need to rejet. Dynojet kit will get you close, but they are not available for all models, namely those with VM carbs.

[koolaid_kid]

My money is on an 81 850.

[MisterCinders]

It's an 81 something.

[firstGSrider]

Koolaid kid gets it and you can tell i'm new to this. It is a 1981 GS850GL and I will be doing pod filters and planning on the dynojet kit. Should that be a stage 3 kit? And are the sizes they include in that correct for the most part or is it possible i could need some adjusting? Which pipe will sound better 4-1 megaphone or 4-2 turnout from MAC? I just got the bike home today and it idles kind of erratic. The choke cable is frozen and I already have a replacement one. I think maybe the throttle cable is rusty because when I rev it it takes a sec to come back to idle or could it be the carbs still dirty or old gas? I haven't started taking stuff apart yet so i'm not really sure. I know it needs intake boots because there is sealant on all of them and the boots look to be orginal. I've got my work cut out but all winter to do it.

[hikermikem]

A complete carb disassembly & clean is in your future.
The beginnings of a wonderful learning experience.
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