Valuing a bike that has a fault is always going to be a tricky one, especially one with an �unknown� problem. A bike with a known fault, say for arguments sake a broken gearbox, is going to be easier to sell in many ways because a potential buyer can assess the repair cost with some degree of accuracy, factor it in against the market value and pay accordingly. In other words a value can be calculated.
However, with a bike like yours, the problem could be cheap to fix, or it could just as easily be very expensive. It is almost impossible to work out a value. The bottom line is, it is only going to be worth what someone is prepared to pay for it. There will be folk out there who will be prepared to take a gamble on the fact that it might be cheap to sort and pay a generous price, but there will be just as many (if not more) who will only want to pay a pittance because it could potentially work out very expensive. The question is who�s out there at the time you advertise? You may get lucky � you may not? It�s in the lap of the gods.
Breaking or dismantling the bike for parts is potentially going to bring in more money and be a more certain proposition. A mate of mine who is into automotive recycling, always works on the fact that he reckons the sum total of a non-functioning bike�s parts is going to be about equal to its retail value in good working order. There is a catch though, once you factor in the time it takes to dismantle a whole bike, clean, catalogue, photograph, package, advertise, sell and mail the parts individually this idea suddenly becomes a slightly less attractive proposition! There�s another catch too � it could take months, even years to get shot of all the parts and see the full financial return.
The final option is to try and fix it. If you were me (which you�re not), I�d try this option first but, and this is key, I�d set myself a maximum time limit and budget to get it running � and stick to it rigidly. If I couldn�t do it within time/budget, with a wife, kids and a job to worry about, I�d call it quits and stick the whole thing on ebay, cut my losses and walk away.
The above of course is just an opinion, but I hope it helps. Sorry I didn�t mention any figures; I wouldn�t want to suggest a value because that would just be guessing!
Only you can make the choice�