I have recently acquired a 1966 bsa spitfire mkII with borrani race wheels. as ive been told this is to be a factory race bike only available to top dealers or factory sponsored riders?
Do you mean this model of bike or the particular bike in your posession? If it can be proven that the one you have was specially tuned and/or raced by the BSA works then it will naturally be worth more to collectors.
However the unit-model Spitfires themselves weren't produced specifically for racing, more as a super-sports model to surpass the Triumph Bonneville/Norton 650SS range of the market.
A lot of things affect this particular model's value, but bear in mind it is an intrinsically sought-after bike. The immediate downside to yours is the excess chroming - people nowadays are tending to favour originality more. What can drastically change the value without even seeing the bike in question are two items: a) the wheels; and b) the carbs.
The mkII spitfire came out with the BSA racing front hub - the '190mm' as it is referred to - laced into flanged alloy rims. I'm not sure off the top of my head whether the rims were Borranis or Dunlops, but that's not so critical as the hub. If you don't have the 190mm brake the bike's worth less to buyers (worth less not worthless haha).
More importantly though is the carbs. When released the mkII spitfire had a pair of Amal GP carbs with a central float that looked something like a small hip-flask. These are now all but impossible to replace and in many cases they have been removed and replaced with more sensible Concentrics. No GPs diminishes the value.
But apart from these two especially racey items the overall factors governing value are the usual - what condition it's in, how much of it is there and so on, but as I said previously genuine MkII BSA Spitfires are a sought after and valuable prospect, so expect a few dollars even with a chromed frame.
