R1150GS Remus exhaust - how much extra power?

[DaveGandT]

I'm thinking of buying a R1150GS 2001 this week (I have a 2003 Transalp, first bike which I've had for 2 years but it is time to get something bigger). The bike has a Remus exhaust fitted - looks like the Remus Innovation. In getting a quote from eBike insurance it asks about mods: the options for a different exhaust are same capacity, <5% increase and >5% capacity increase. For now I've ticked the < 5% increase - the Remus web site doesn't have any info on increase in capacity/power! - but I'm worried that I tick the wrong box and invalidate the insurance.
Does anyone know what difference the Remus exhaust makes?
Thanks in anticipation of any help anyone can give. Cheers.

 

[Steptoe]

The only power increase is in decibels

 

[Wreford Miles]

power to weight may be up a smiggen

 

[Dunk]

Don't worry mate, the power increase, if at all, is neglegible. I've always told my insurer (Carol Nash) that it wasn't 'performance enhancing'.