Any 3/8" duplex chain from a reputable source & of genuine manufacture will be fit for purpose. The chains I have, & have fitted, include Iwis, Regina, Renold, TDCross & Morse. I rate Iwis no better, or worse, than the other manufacturers mentioned. As a design engineer, I have incorporated many power transmission components that have had to conform to rigorous Standards, & chain is no different if it is genuine, which it is more likely to be if obtained from a power transmission specialist, rather than from many a ‘Lambretta specialist’
I have made up chains from 79 to 83 link using either proprietary ‘one & a half links’ & connectors or by riveting in half links. None of the many I have made have failed or stretched to excess. On the other hand, I have witnessed a couple of occasions where chains made up by a ‘top tuner’ have failed due to the nature of the jointing method. The decision on brand depends upon the cost of, say, a five-metre pack when required, & I am fortunate to have some good contacts.
Timing chain stretch is not the stretching of the timing chain, it is an elongation of the timing chain caused by wear to the chain’s components. That is where the quality is designed & built in.
The Indian manufactured chains called Rolon are dire. I loaned one of my own chains to a race team @ a meeting (as we used to do to help others out) & got a brand new Rolon back in exchange. Never again….
