It's the Economy...
 

I also always measure volume over distance (with odo correction off GPS or autoroute markers); an old habit predating digital consumption read-outs. Though I do wonder about dodgy fuel bowser calibration sometimes.

Maybe the venting problems affected this particular bike.

I'd imagine 70 is as good as you'll ever get from a relatively powerful 790.

This talk of the 'CRF800L' using an NC motor could be interesting wrt economy, though it probably wont't be any kind of KTM in the dirt.

I wouldn't want to own one, but the 310 appears to be an exceptional economical machine; even on a Himalayan I only ever averaged 78.

The more I think about it, the more a 690/701 fills a sweet spot for an all-terrain travel bike: enough power for the highway, great mpg and as light as can be expected. Maybe the PR7 is the same. Modern Teneres.

I also thought about the KTM 690 enduro R as my next adventure bike but new AT850 could be as well if they not go cheap on suspension like Honda usually does. Advantage of new Africa is better reliability, better wind protection, better carrying capacity and better economy all which are beneficial on long hauls.

I don't like having to make loads of modifications to a bike, which was why a decade or so back I liked the XT660Z Tenere as it was ready to go 'out of the box'.

If I was buying now I would be temped by the 701LR with its 25 litres of fuel capacity. It's a pity Husqvarna didn't go the whole hog with a rally cockpit. And the instrumentation has taken a backward step on the 2019-20 models of both 690/701.