Mex Mex -
Google this or similar REP SPANNER 24mm + Tyre lever. Carry only one and use a spanner as back up lever.
I always carried a throttle cable.
Domino parts.
1/2 link and two splits - easy to repair chain.
A white piece of rag to put parts on if you have to dismantle, eg easy to lose float bowl nut in the heather.
Look for odd combo spanners from machine tool kits eg 10mm 13mm combo
Fuel?????????
Don't carry water unless you really need to, super warm week? - frequent fuel stops.
Some one said rubber band tool into groups - works well.
Remember, good bike prep is essential, thread lock the bolts you would not consider undoing in the field, if your lucky you wont touch any of the above all week.
Fred.(oops, Jacks account).