Frequently check:
1. running of joints (links must move freely)
2. plates, rollers, pins and o-rings are not damaged
3. presence of all o-rings, all rollers and the clip (where foreseen)
4. clip (where foreseen) is not too much wear

TENSIONING CHECK AND RE-ESTABLISHMENT.

After first 80-100 km with a brand new chain, it is advisable the check and re-establish the correct tensioning, and subsequently every 300-400 km.
This check is done after having aligned on the same line the front sprocket, the swingarm pivot and the rear sprocket, and by verifying that the chain can freely oscillate a total of 10-15mm up and down (while the upper strand is tight).

CHAIN WEAR INSPECTION.

Place the chain upper strand under tension.
Measure chain length with a caliper or a precision drawing rule
for 520, 525, 530 and 532 chains a number of 16 links and verify that it is not longer than 259 mm (traditional chains) and than 156,5 mm for sealed chains
for 415, 420 and 428 a number of 23 links and verify that it is not longer than 298 mm for traditional chains and than 295 mm for sealed chains.
Correct measurement of indicated number of links is carried out from centre to one pin to centre to 16th pin (or 23rd pin) following, according to chain length.

Note: present chain manufacturing characteristics have produced absolutely ineffective the old check procedures, as i.e. the side arrow or, even worse, the upper strand shaking. These systems make appear as work also a new chain.