Retro fitting standard pipe
 

I bought and fitted a standard exhaust to mine today and initially it really struggled start
Any one have an idea why this would be? It seems okay now though thankfully. I'll try and give it a test run tomorrow, beer got in the way tonight!

It was probably full of cobwebs! ;)

If it's going fine now, then I wouldn't worry about it.

I'm wondering if the insides have been tampered with as it seems louder than it should, hard to judge without hearing others
I'll see what it's like tomorrow

Is/was there any evidence of the top of the silencer having been cut open and welded up before you fitted it? If so, it may have had the catalyst removed, which is a fairly common modification.

Joking aside, I still think that the trouble you had initially would have been debris inside the silencer. During storage all the built up soot tends to flake and come away from the internals and will clear out on first start up.

Only issue I noted were the loose end caps, I drilled out some rivets and replaced them. Everything else looks standard and aged

Probably just loads of soot and debris that had flaked off the insides during storage then and just need blowing through.

Just been for a 100+ mile ride wig the standard pipe with no issues, still has a nice subtle burble on the over run. One happy camper!
Now to eBay the old one...