Erratic fuel gauge

Okay, here's the thing. I am a new to Silverwings virgin and when I got the bike last weekend, the fuel gauge was flashing just one digit at the bottom. So off I go to the local rip off garage and fill the tank. Surprised to only get about £12 worth of the good stuff in, after which a mate tells me he can get about £16.00 from empty.
Gauge showed full for the return trip to the garage.
Rode the bike the other night, only about 50 miles, but during that time, the gauge was again flashing just one digit, although it did show full for a bit of the journey.

I am assuming that it is the sender unit inside the tank that is playing up, unless someone can tell me otherwise?
Next question is, how do I get to access the tank and whatever may be playing up?

If, IF, you were on this side of the pond I'd suggest that you do multiple half-bottle Chevron Techron treatments to the next several tanksfull of fuel. More than likely the fuel sending unit has varnish deposits which are causing the erratic fuel gauge condition.

Use the blue tab Search function, above, to find what others have posted regarding fuel gauge issues.

Best to review the fuel tank removing procedure in the FSM. You do have the FSM, don't you?

Tim

Yep it's in the tank, the 'fun' bit's..........

Remove saddle
Remove sparkplug cover
Remove floor mats
Remove lower skirts
Remove passenger footpeg mounting plates
Remove central floorboard section

If it's been standing for some time with little fuel in, the sender might have become 'sticky', might be worth running some fuel addative for a few tanks, see if it frees off.

Typed that ^^ while Tim was also typing, concensus is much the same IIRC there is a Redex product that cleans gum from injectors, that or something similar might help

Ohhh as reccomended by Tim (&similar price to Redex), Techron is over here as well bud ............

https://www.ebay.co.uk/itm/NEW-Techron-PEA-Concentrate-Plus-Petrol-Fuel-Injector-System-Cleaner-350ml-/273243314715?_trksid=p2385738.m4383.l4275.c10

Thanks guys, sounds highly likely that it is varnished up, since it seems intermittent. I will certainly give it a try with additive, since I have some good stuff that has worked successfully for me before, Forté which I pretty much swear by.

Highly likely that the bike has been standing for a good while, as the PO was a bit of a wheeler dealer and has a good few bikes.

I don't have a FSM as yet Tim, having only just got the scoot and not 100% sure I will be keeping it yet, I am not going to spend too much on her, until I am sure. I have shelves full of Honda, Clymer and Haynes manuals, but not one for an Swing..... yet.

Cheers for the advise lads.

Rumor has it there is a FJS600 FSM online. But you'll need to search

i replaced head light bulbs and in doing so had to unplug the dash.. fuel gage had not worked for weeks maybe months while the plastic and dash was out i cleaned put dialectic paste in all connectors ... gauge has worked from then on.