I HAVE HAD 3 MOTORS FROM ORIAN AND ALL THREE HAVE GIVEN ME PROBLEMS. THE FIRST THING TAT YOU NEED TO DO WHEN YOU GET IT IS REPLACE THE BRUSH SPRINGS. THE ORIGNIAL ONES JUST ARE CRAP.
Thats a bit of a sweeping statement as it depends on the wind and application and how you build them.
I think what you may be reffering to is the tendency for the spring to come out of the holder from std. This is easilly cured by removing the spring and gently opening up the last coil slightly so it seats in the holder much better. Not great I know but not the biggest job either.
In terms of springs, well the normal modifieds and tourings come with medium springs (41391) while the steenari and hara versions come with medium hard (41392) The newer reinhard winds - which I would highly reccomend below 10 turns come with the much harder MR035 inox springs (41386) a little too hard IMO unless running circa 7 turn on very tight circuits.
As for setup I would suggest the following for 6 cell modified touring cars on tarmac. This is based on the orion or peak touring range wich uses a 4mm rpm blank down to 10 turns and a 5mm torque blank below 10 turns. Also use the same setup for either the Orion Reinhard range or the Peak Spashett range.
12 turn open / fast circuit use medium hard (41392) on the -ve and hard (41393) on the +ve. Sprint edge brushes and 7mm timing, FDR of around 6.1/1
12 turn tighter / twisty circuit use medium hard (41392) on the -ve and hard (41393) on the +ve. Sprint edge brushes and 8mm timing, FDR of around 6.6/1
10 turn open / fast circuit use medium hard (41392) on the -ve and hard (41393) on the +ve. Sprint edge brushes and 6mm timing, FDR of around 7.2/1
10 turn tighter / twisty circuit use the MR032 inox medium springs (41382) on both the -ve and the +ve. Sprint edge brushes and 7mm timing, FDR of around 7.7/1
8 turn open / fast circuit use the MR032 inox medium springs (41382) on both the -ve and the +ve. Sprint edge brushes and 4mm timing, FDR of around 7.9/1 (if you need more top speed you can use the medium hard -ve and hard +ve setup with a FDR of around 7.7/1)
8 turn tight / twisty circuit use the MR032 inox medium hard springs (41383) on both the -ve and the +ve. Sprint edge brushes and 5mm timing, FDR of around 8.6/1. For really tiny circuits you may need to push up to nearer 9.0/1 but we have never had a need to run that low as our circuits here in the UK are usually pretty open.
Another good practice is to ignore the label and score a mark on the opposite side of the can exactly through center of the pressed ident on the can - thats 0 timing. Then take off the endbell and put a straight edge across the two enbell screw holes and file a small notch in the endbell - opposite side to the standard notch in the endbell. This gives you an accurate position to measure the timing from as the labels are not always positioned accurately. Then measure the timing using a soft tape measure in millimeters between these two marks . Far more accurate and repeatable on all motors then.........just make sure you file the notches accurately!
Hope thats of some use to you all