starting problems/disk break upgrade

[andreasb]

When the outside temperature drops below 65degrees F my bike (R80GS/1992) does not start up easily.... I have to use the choke and turn the starter for at least 5-10 seconds before it kicks in....sometimes one cylinder at a time...
Recently I had a lot of work done on the bike (a Greek mechanic using a Greek 'torque wrench' had over tightened one of the rockers and eventually the bolt holding the cylinder ripped right out of the crank case/engine block).... it took a lot of patience and three days to fix (threads recut, piece of metal welded to end of bolt and threads recut as well, refitted) and at that time I changed all the oils, replaced or cleaned filters (except for the K&N reusable air filter...only knocked out most of the accumulated dirt)etc.
Also had the carbs balanced, spark plugs replaced but still no improvement...wonder if the starting difficulties could be electrical? Too weak of a spark...(spark looks ok).... and if yes, what can I do to check it (do have a voltmeter)
And to make things even more 'complicated' I have noticed that the plugs end up looking rusty red brown even after hours of riding at medium rpm (4000)...fuel consumption is good though at around 5.5 liters/100km....
Once the bike has warmed up it runs smoothly and without any problems...it is starting the bike cold that is difficult.

On a different note...my floating front disk break started to make terrible noises and I head the rivets slightly tightened (but still loose) to get rid of it...now they are screeching at times...and I am thinking about 'upgrading the disk breaking system' completely... since the breaking power is pretty poor with loads of weight.
Does anybody have a suggestion on how to get more breaking power and at the same time NOT spent an arm and a leg...was quoted $1000 for a new, dual disk breaking system...but there must be options, right? Unfortunately, the disk might have to go....
Andreas