Unfortunately your claim is through them and they hold all the cards.
Strictly speaking a vehicle is only a write off if it would cost more to put back the
way it was at the time of the accident, than the
market value. The market value is that as quoted in Parkers Guide or similar and your bike should fall between the range of values quoted. Unless you have a new for old clause which is doubtful.
On top of that, generally, it will only be classed as a write off, if one of 2 things happen.
1) They pay you out for the vehicle and they keep it, or
2) If a police officer attended the scene and put a tick in the box marked "probable write off" (or similar) in his report book because he thinks it is at the time. This is to stop death traps being put back in the road.
Either of the above generate a form DVLA V23 write off marker registered against your bike at DVLA.
Have a look at
http://www.crimereduction.homeoffice.gov.uk/mso06a.pdf for a bit of info from the DVLA regarding classes of write off.
In short you are at their beck and call. You may be able to negociate with them a bit and you will need luck and good reason for that (for example: very good condition, factory accessories, low mileage). You need to bear in mind that their aim is to pay out as little as possible and yours is the opposite. They will make stupid offers that they want you to accept.
When I bought my last (and only) new car, I was advised to take out an extra insurance to cover the difference between what I owed on the car and the value after taking it out of the showroom (i.e second hand when only 1 day old). This was just in case it was written off when nearly new, as the market value was a lot lower, as a second hand vehicle (although new), than the amount I owed on it.
One other thing, you state you were knocked off the road, if you can prove this and the other party can be held to be 100% responsible, (and hence pay 100% of your claim,) you should not be liable to any loss of "no claims bonus" or future loading.
Hope this helps, others may be in the insurance industry and know more.
The bottom line is that no one ever wins after an accident.
Ray