[fizzwheel]

If you can't afford to insure the bike with modifications, then don't do the modifications in the first place.

TBH if you crash, most companies will only pay for the bike to be put back to standard anyway, however if its pinched and the mods you've done make it more desirable cosmetically wise, then you might find that the insurance comany may well refuse to pay out.

I'm not sure of exactual technicalities, In my opinion its best to declare it all and then you dont have to worry about it, if anything does happen.