Hi fellow TR1 riders!
If you need a carb diaphragm, a now discontinued part!
try:
NRP Carbs and Diaphragms
Unit 2, Station Approach,
Victoria Station,
Manchester
ENGLAND
M3 1NY
TEL/FAX +44 [0] 161 832 8646
http://nrp-carbs.com/
Manufacturers and suppliers of Diaphragms
and spares for Japanese carburettors and Fuel taps
They are friendly and helpful and can supply diaphragms, jets  and service kits for ANY Jap carb 1960's to 2005.
they are also cheap! £35 for a diaphragm (about 50 euro)you have to send them your slide and they fit a new diaphragm to it
hope this helps someone
Bob