How much backlash?

[Donut 77]

I have the bike in 6th gear on a paddock stand.

Plugs are out.

First thing is I can only just about push the back wheel round.., then it will suddenly roll a bit as the cam lobes settle on. This is probably all fine, although I was expecting it to be quite a bit easier in 6th with no compression. Also, when I roll the wheel backwards (not sure if this is a good idea) but I can hear the gears slightly more? Why is this?

Second thing; there seems to be about 50mm of tyre rotation between the gear engaging going forward and backward. I think this is called backlash. Is this amount normal? I would expect this to be quite tight, with some allowance for chain slop, but not 2”

If anyone has their bike on a stand, could you perhaps put in top gear and see how much the wheel rotates before it makes positive contact between forward and backwards please?!

Many thanks as always.

[tony.mon]

It's ok. Check the cush rubbers in the rear wheel hub.
That's cumulative backlash in the rear wheel, chain, transmission and primary drive, also the cam chain slack.
It all adds up.

[Donut 77]

Hi Tony. Cush rubbers are tight - I put some plastic packers in there. Drive chain is brand new. This is just transmission I think (as in, everything else you mentioned)