Just preparing my bike for the Dragon Rally, but not happy with the way the valve collets sit. They don't seem to go all the way down the retainer. Has any one got a photo of how they should fit.

Also, what are the best solutions for removing an old petrol tank liner and replacing the liner with a more ethanol resistant liner.

Kind regards

Pat

email (option): sacombsashtrees@hotmail.com

I haven't got a picture. But M20 collets are longer than most and give the appearance of not being fully home. They have an extra bit stuck out....There must be a reason?
As far as your tank liner is concerned. I have had to do it a few times and bought the removal solvent from http://www.auto-cycle.co.uk/
It's quite simple if you follow the instructions and possible to do it without damaging your paint. Ron

email (option): ronpier@talk21.com

Thanks Ron.

I have a Triumph T110 and BSA A10 and the collets don't stick out much at all. I guess the collets on the M20 aren't going any where as the springs force them in place. I will check the clearances once back together and again after a few miles.

Thanks for the tip on the liner. I have been running the bike with in-line fuel filters which don't look good, but keep the orange deposits from the liner out of the carb.

Kind regards

Pat

email (option): sacombsashtrees@hotmail.com

M20 collets are longer because BSA knew what they were doing.
The extensions make it a simple operation to remove and refit valves without disturbing the cylinder.

Think of the collets as having handles for your convenience.

email (option): n.gentner@bigpond.com

Hi Neale

Thanks for this. As I have removed the barrel, what is the best way to tighten down the one difficult nut that holds the barrel to the crank cases. I cannot seem to get a socket on it or a spanner. Do I grind/flat a good spanner?

Any ideas greatly appreciated.

Kind regards

Pat

email (option): sacombsashtrees@hotmail.com

A good quality ring spanner has always worked for me.

Do you have the correct nuts?

The correct nuts are reduced hex and slightly taller, "normal" nuts won't permit the use of a ring spanner.

There are many old bike situations where the use of sockets is impossible, when these things were first conceived, the socket had not been invented, let alone in widespread use.

email (option): n.gentner@bigpond.com

Hi

Yes correct nuts. Maybe my ring spanner is too long.

Kind regards

Pat

email (option): sacombsashtrees@hotmail.com

Yes I always manage it with a combination spanner, by little nips and sometimes by tipping the spanner up to the widest gap further up the mag to get enough turn to get the spanner on for the next bite. BSA actually made a special cranked spanner for the job. Ron

email (option): ronpier@talk21.com

Thanks Ron.

email (option): sacombsashtrees@hotmail.com

The M20 collets do look odd when fitted if you are used to OHV engines. In the past the exhaust valve and seat in particular needed fairly regular attention and with the barrel in place on the cases there wasn't the benefit of gravity when it came to replacing the collets...So it was all to aid replacement in that particular circumstance..I have to admit when in short supply for OHV motors I have removed the M20 'extensions' and converted them for use in those types....Ian

email (option): Ian@wright52.plus.com

Thanks Ian

email (option): sacombsashtrees@hotmail.com