Unlike most riders, I am curious to know what my bikes actually weigh – especially before and after a makeover. 
For years I’ve used the bathroom scales trick; balancing the bike with the scales under one wheel, then the other then add the two figures.

You will find this old thread on Advrider with the usual mix of sneering, humour, muddled thinking and bare-faced logic. Read to the end and you’ll see the single bathroom scales technique has been proved to vary at just 1% over other methods like recycling weigh stations or hanging scales. Also, the over-thought need to horizontally level one wheel to match the height of the other resting on the scales has proved not to be significant. But the ground surface must be horizontal and the actuating feet under the scales must all be in contact with the ground (or stick the scales on a board).

I went to a car park with lots of space and excellent horizontality. It can take a few goes to get consistency; eventually for my GS500R I got a reading:
Rear: 104kg
Front: 86kg
Total 190kg with half a tank of fuel, or about the same as a BMW Sertao.

That is about what I expected: a few kilos added over the 186kg claimed stock weigh following the addition of a DR650 fork, crash bars, the pipe rack, SV shock, screen, bigger bars and a handful of other bits. Don’t know how the 19-inch SM Pro wheels with Tubliss compare to stock GS500 casts. You’d hope a small weight saving but cast wheels have a habit of being lighter

Since then I got some Salter Razor (right), now only 14 quid off amazon. Who knows about actual accuracy but this one is much more consistent than the round one above and much easier to use.

BMW X Country ABS, full tank, plastic handguards
Front wheel 73kg
Rear wheel 90kg
Total 163kg – a very good weight for a pokey 650, if I may say so myself.