I agree with most on here, any or a combination can cause a chain to have more noticeable tight spots than is ‘normal’ for a chain in use.
I know all the bikes I’ve had in the past had tight spots in both primary and rear chains, well - that is except my Velocette LE (shaft driven
). I’m sure you know this Richard, you rotate the wheel to get the tightest spot in the middle of the top run and adjust it to have 1.25” slack at that point. My point here is that the very fact that the instruction books say adjust at the tight spot is confirmation enough that it’s fairly normal.
I agree with Kiwi GF I’d change the connecting link for one of the correct pitch. 0.030” = 1/32” whether over or under the correct pitch of 5/8” it won’t be great for the sprocket teeth.
Also bergers comment about after market parts not being what they should is something to consider. Most of us will have had traumatic experience of that.
A few years ago I bought a rear sprocket stamped 'Made in the UK' by LF Harris, along with a rubber sealed bearing for it. When I tried the bearing in the sprocket to my surprise it just fell in the hole. Assuming the bearing was imported and at fault it was a phone call and a drive to Monty's Classic Motorcycles in Cornwall. Luckily I took both the sprocket and the bearing with me. When I arrived Monty had already fitted the same type of bearing in the same type of sprocket to test it and he told me he had to press it in. I turned the sprocket I had, with bearing in hole, upside down on the counter and the bearing just dropped out. Puzzled, Monty got another bearing and tried that in my sprocket, that also was loose. It turned out the UK made stamped sprocket was the faulty part. Monty's face was a picture of disbelief, the Imported bearing - fine, UK made sprocket - not. For those who do not know LF Harris is a well known and respected supplier of classic motorcycle parts and it’s founder was Les Harris who started manufacturing Triumphs again. No doubt the parts are now sourced overseas.
