It seems unlikely that the fuel pump itself is the problem here. If it were, then I suspect the engine would not be running as the fuel injectors will not run without adequate fuel pressure.
But even low mileage bikes can have a plugged filter. All it takes is one batch of dirty fuel and it's all stopped up. For some odd reason, however, Kawasaki doesn't list the filter for the C14 separately. But other models use the SAME filter and it's fairly easy to replace it. The Kawasaki PN for the proper filter is 49019-0013. It's under $15 as I recall. I suggest getting the genuine Kawasaki part. There are knock-offs on EBAY and Amazon and they are definitely lower quality.
The sender or the float could also be bad, but that's a separate assembly. There is a procedure in the SVC MANUAL for testing the fuel sender.
as for the 'fuel level' sendor, vs the 'low fuel level' indicator, the low fuel switch is a solid 'chunk' thing, and no adjustment can be made to it, but it comes as part of the pump assembly...
the fuel 'gauge' sending unit, seems to be working, as you are getting 'bars showing', so maybe a slight 'bend' of the wire arm will correct it's function, and result in a full when full reading on the gauges.
we just recently re hashed this whole thing, and I supplied very pertinent part numbers, and resources for the filters, pumps, and other stuff...
as for the Kaw microfiche, and the filter... you simply did not check the more recent model releases of 'available parts, and lists', it's been placed on the current models now, and can be easily found.
so don't spend big $$$$ on a pump, you can get them cheap, ( for like $70...) and they do work correctly,(we have positive feedback from a few people that have bought, and installed them), as for the filter... it's just a sump 'screen' sock, and whatever you use works... same place the pumps are sold from also has filter socks, cheap, and they function.
I'll just ad a 'copy/paste' of what I posted on the 'other site'....
I had forgotten about this post of mine from last year. Figured I would fill everyone in on the outcome. As the weather cooled off last year, the problem went away and I forgot all about it. I ride almost every day and it never happened again.....until two weeks ago. I had gone to my place in the mountains for a few days and was out riding with a buddy. I took off fast and about 7k rpms in second gear it fell on it's face hard. It came right back and ripped on up to redline and then didn't do it again the rest of the weekend. On the way home after running 90-100mph on the interstate for about an hour, the problem came back very pronounced and stayed. The bike would barely maintain 60-70mph and ANY increase in the throttle would cause it to stumble. I babied it the last two hours home and went straight to the dealership to drop it off. Fuel pump wound up being bad(which was my suspicion all along) and they said the fuel filter was very clogged. I think the 95 degree temps, coupled with my spirited riding style just finally did it in. Anyway, sorry to bring back such an old post but I figured I would give it some closure. 
Thanks for posting that . Another person contacted me about the same symptoms, and yup, it was the fuel pump. I guess nothing lasts forever! Steve
bummer, but there is a good source for fuel pump assemblies now, for pretty cheap...
http://forum.cog-online.org/fuel-cooling-and-oil-systems-59/repacement-fuel-pumpfilter-combo/msg636925/#msg636925IMHO, it's kind of a 'chicken or egg' thing, like which comes first...
I think that when the first symptoms surface, if the pump is pulled, and filter replaced, the pump will live on for a long time... trouble is, it gets passed off, and by the time the blockage is sooo bad it can't flow, it stresses the pump to the point of failure. This is based on what I've seen in years of car/truck issues, where this occurred (to me personally), and because I waited sooo long to replace a filter I have a truck sitting right now, which ran after I replaced the filter, but much too late, and the pump failed about 2 months later... now it sits, because I can't pull the truck bed off to replace the pump all by myself.. and dropping the tank ain't happening..
When it occurred on my other truck, same engine and manufacturer, I immediately replaced that filter, and the truck is fine, 3 years later... periodic filter replacement is easy, compared to cost and p.i.t.a. fuel pump replacement.
Kaw clearly caught on to the symptoms, and the issues, as they actually now have a pump filter and o-ring 'kit', for curing the problem when someone brings one in... unfortunately, It never hit the MicroFiche untill 2017... and anyone bringing in a pre '17 bike, they will gouge you for the 'full monty' pump assembly, because they never read those 'service bulletin updates'..
well, they probably do read them, but when they type in any bikes date pre '17, they can claim ignorance...bummer...
I've had mine apart a couple times, to 'flush' clean the filter, and replace it, never needed the expensive kit with the o-rings, and tiny screws (in kit, because they figure you will loose one, or the TECH doing the work will at least..)
kit is
99999-0521 KIT,FUEL FILTER
$62 from RonAyers... for like $15 worth of parts...
a bit pricey, but hey...
the COMPLETE Quantum pump, referenced up top, runs $70, and has a filter in it... they also sell filters for $15 for 3 filters.
filters are cheap, and easily sourced.
Kaw p/n 49019-0013
or
https://tinyurl.com/y7c2zhh2best of luck.
hope this clarifies....
