I had a modern B-TH "mag" on my Meteor and it developed a misfire. I swapped out fuel, spark plug, plug wire, played with position of the high tension lead and made sure the kill wire was not grounded. By process of elimination, it seemed the fault lay within the BTH. I sent the BTH back to Peter Nugent in the UK (from my home in Texas) and he proclaimed it perfect. He sent it back and I reinstalled it. The bike still misfired once up to operating temperature. We installed a used, stock Lucas magneto from another Vincent single and the bike ran fine. I sent the BTH back to the UK a second time (each round-trip to the UK costing over a hundred dollars in shipping) and Peter offered to rebuild the unit for free. He returned the rebuilt unit to me, we reinstalled it and the bike continued to misfire. I eventually bought and installed a rebuilt Lucas magneto from a fellow Vincent owner and the bike has run fine since then. I'm now left with a very expensive B-TH that I don't feel comfortable selling to anyone else because I can't vouch for its performance. I told Peter Nugent all of this and he didn't respond or offer to make things right. Very disappointing. His bench test consists of spinning the "mag" with an electric drill while it's connected to a spark plug and using a timing light to determine if the unit is firing the plug. It's an inadequate test given that the demands on the "mag" are much greater when the plug is experiencing elevated temperatures and pressures found in a combustion chamber of a running engine. The whole experience with B-TH left a bad taste in my mouth. Caveat emptor.
