GRiSO 1200 Header damage

Hi to all. Take off headers to polish it and found out that the inner layer of the double layered left head header is totally damaged. I wonder what could cause that. Also noticed sufficient lack of power after 7000 rpm.
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It certainly wouldn't help performance. Best bet would be to source another second hand pipe. I've got half a dozen but getting one to you would be difficult and pricey. Try one of the European suppliers like TLM.

Oh, and out of interest what do you mean by the rev limiter being set at 7,000? Do you mean the warning triangle flashes at 7,000 or is it that the engine stops pulling about there?

I have a set of stock headers if need be. Just needing a polishing.

Pete Roper wrote:

It certainly wouldn't help performance. Best bet would be to source another second hand pipe. I've got half a dozen but getting one to you would be difficult and pricey. Try one of the European suppliers like TLM.

Oh, and out of interest what do you mean by the rev limiter being set at 7,000? Do you mean the warning triangle flashes at 7,000 or is it that the engine stops pulling about there?

Thanx for reply. I have already ordered a used pipe (new piece is too pricey) and tried to install the normal pipe from my mates bike - much better pull after 7000 rpm to 8500 rpm. But still it feels like it could be better. 
Triangle flashes at 8400 or so.

That's like looking down someone's intestines....with polyps...

Can’t imagine why did it brake down

Manufacturing fault? I've never heard of one collapsing internally like that. Your guess is as good as mine.