Its got to be worth a shot 
I would get on the phone to the RAC and speak to whoever issues the Carnet. Be careful what you tell them on the phone as your dealing with an 'official' document and if they think your telling porkies, they may refuse to issue one. I would be asking what the indemnity insurance is for/does and what happens if something happens to the bike in Iran. Based on what they tell you, you can work out if its worth the risk of undervaluing your bike to £1000.
Bear in mind, Iran on the whole is very safe but riding in the cities is mental, I would put it 'up there' with Delhi for sheer nuttyness!
Good luck, its definatly worth the effort
I would get on the phone to the RAC and speak to whoever issues the Carnet. Be careful what you tell them on the phone as your dealing with an 'official' document and if they think your telling porkies, they may refuse to issue one. I would be asking what the indemnity insurance is for/does and what happens if something happens to the bike in Iran. Based on what they tell you, you can work out if its worth the risk of undervaluing your bike to £1000.
Bear in mind, Iran on the whole is very safe but riding in the cities is mental, I would put it 'up there' with Delhi for sheer nuttyness!
Good luck, its definatly worth the effort