Some things I know about circlips
1) Seegar circlips are crap. they loose there tension ,plus the the ends with the eyelets can break of from vibration. I learnt that from a 250 ccT70 that had them at the gudgeon pin. That thing revved.
I always grind a chamfer on the end of the gudgeon pin for use with wire circlips.
Never use wire circlips with the ends bent 'round for fitting/removal on pistons. They brake off at high revs. On other applications the tags can actually lever the clip out of the groove. The chamfer on the pin wont reach the wire.
On larger circlips in gearboxes, fork legs etc flat circlips should be squeezed by hand across their diameter to tell wich way they dish, so that they can be installed the way that wedges them into the circlip groove.
Circlip grooves are machined round for wire circlips and square for flat circlips.
When installing flat circlips, look at the way the ends are cut, they are at an angle to assist circlip pliers to grip.