at present i am running a telemetrix speedo reading the bolt heads on the lobro joints (saves having to add the final drive ratio into the equation) but the clearances are to close for my liking at 0.127mm' a bit of play in the bearing and the sensors ruined. just been in touch with caerbont to see about the 4 magnet sensor only to be told they do not recommend the use of this type of sensor any more. but have modified the bolt head type to now read from a gap of 5mm.
regards
tony

Did they say why?

no but will try and find out why

Now this is isnteresting, since my speedo soesn't seem to work and is one of theirs with the 4 magnet sensor!

I think I'll be phoning them!

the reason is the magnets fall off at high speed and cause reed to stay open causing loss of signal to speedo.....even though the use of araldite is reccommended........any-one had any problems
tony

This is very interesting for me too. I´m running the speedo from Telemetrix with the 4 magnet sensor.
And the speedo goes wild sometimes and I´m now on my third sensor

Did anyone call them and got an answer?