I have now managed to get a new one off ebay after having a search running for 6 months, but I would like to mention Peter Bowley of UKCarbs who has been very helpful and was going to repair the current one.
Before I had not found any way of fixing my carb (I posted here)and my BX was looking like a scappage candidate
If anyone has carb probs I am sure Peter will try to help, from talking to another forum member I know that they are sometimes a problem.
[email protected]
NB This is from personal experience and is not meant as an advertisement!