BSA A65 Wont start when warm

[A65rider]

I have a 1966 BSA A65 the engine of which had a complete rebuild by SRM in Dec 2016 (1800 miles ago) and is fitted with new Amal Concentric carbs. When the bike is cold it will start first or second kick. Of late, once the engine is well warmed up (12miles +) and is then stopped it is very difficult to restart. I've tried all sorts of starting methods but normally if I put it on its mainstand leave it another 5mins or so (irrespective of how long its been standing but usually less than 30mins) it will go. I've changed air cleaners and plugs etc but this made little difference. Anyone any thoughts. Rgds

[iansoady]

I would be looking at either over-rich carbs (does it start from cold without air lever / flooding) or something like capacitors / coils breaking down. Does it still have its points or Boyer etc?

[A65rider]

I never need the choke (even before SRM rebuild) but starting from cold flood both carbs using the ticklers. The bike has Pazon ignition. Rgds

[chaterlea25]

Hi,
Are there tufnol heat insulating spacers between the carbs and head?
I know that theres not much room on the A65 for them, but you can get ones about 5mm thick that should fit
The carbs heat and the fuel vaporises without the insulators, causing hot starting problems

John

[A65rider]

Yes the insulating gaskets (green colour about 5mm thick) are installed. Rgds

[iansoady]

Have you checked for a spark (should be a nice juicy fat one with Pazon) just after it's stopped when warm?