OK, first one is how do you decide on the correct chain tension? Am using a chaintug.

Second one – rear wheel has a qr which runs through chaintug so there is obviously less skewer. What amount of skewer would be OK as I’m not sure whether I need a longer one.

As always, thank you so much. 🙂

Is the tug sprung or one you just pull down into position on the chain and then tighten the QR?
If the latter then just take up the slack in the chain, do up the QR and turn the cranks. You will feel if the chain is too tight as you turn. In my experience, those type of tugs dont stay tight enough to keep the chain over tight any way so you cant really go wrong. You want about half an inch of movement in the middle at the chains tight spot (meaning the naturally tightest spot when you turn the crank as chainrings are uneven and slightly off centred so they have a slight camming effect on the chain which will cause uneven tension)
As far as the thread on the QR, it should really be most of the way if not all of the way through the thread.
Pics?

Chain tension varies as your rings and sprocket won’t be exactly round.

So find the tight spot if there is one, and make sure it’s got a bit of slackness at that point. It’s hard to judge and describe in words… 10mm of easy play in the chain sounds right to me, but if it’s not jumping, leave it where it is.

With the QR I doubt you’ll have any problems. I’d bet the QR nut is mostly full of the threaded end of the QR, if you see what I mean. One chain tug won’t make the slightest difference.

Thanks for replies. Sorry, I know it’s difficult to describe chain tension but I took it for a wee pootle. Haven’t ss’ed for at least 6 months so it was hard work but chain didn’t feel loose or jump. New chain so will take time to bed in I guess. It’s a Surly chaintug that is tightened before qr is.

Amount of skewer showing before nut went on is about 2cm but I will measure this.

You’ll be fine if there is 2cm of thread showing… I have less than that showing on my 5 Spot and that gets a lot of abuse and hasn’t caused any problems.