Here are a few answers to the questions plus a little more of the changes we made.
yes we are heading for Ushuaia and hope to make it and back to Buenos Aries before the ship leaves that is taking us and the bikes back to the UK on the 29 th. Feb.
Heidenau tyres I purchased were 3.00 X 21 front and 4.00 X 18 rear. the other 2 guys got thees later and fitted 90/90 X 21 and 110/80 X 18. both work fine.
The Cylinders were worn out by the French Gendarmarie, we don't know the mileage covered but it was certainly in sandy and dusty conditions and probably had excessive overheating which I think caused the problem in the Nikasil coating.
We all 3 fitted a new starter motor from Nippon Denso which weighs far less uses less current and spins the motor faster, modern technology is good sometimes.
you can see some of the fabrication done for us at the web site:-
www.overland-solutions.comI will post photo's on next entry.
thanks
Bob