Exhaust woes

[Dazlw]

Hi, I've got an 83 water cooled that backfires on engine deccelaration. The garage says it needs a new exhaust, which to be fair it does. Had a look underneath there are a few holes here and there and there's no clamps on it either. So to my point, from what I can see there is no heat exchanger on the right hand pipe. Question is do I need one and if not where can I get one without one fitted as they all seem to come with one?
Thanks for any help

[itchyfeet]

that heat exchanger is the hot air pick up for cold countries, it is diverted to the carb on choke, not really needed for uk but you can't get early exhaust without it, yours will have long since rusted off but if you look close you will see where it was welded on.

dosen't matter if you don't connect it.

E D I T sorry read that again, heat exchanger only on one side

[Dazlw]

Thanks itchy feet. Think I'll just buy a full system, least I know I will be alright for awhile.