Just back on the road after the winter layup...........I take no pleasure in salty/icy/wet poor visibility on crowded roads..........It wasn't till I removed my ear plugs and started the bike up to pull it forward into the garage that I realised the fuel pump had become very noisy. Certainly wasn't there at the initial warm up. left it to cool and went back out to start it, just the usual hum of the pump. I've since noticed it comes and goes but there is no drop in performance. I can't really establish a pattern but if I were being super-analytical it seems to be more prevalent as I come off the throttle. Fuel filter was changed about 1500 miles ago and looking in the tank I can't see anything untoward.

Any thoughts??

clips that hold the damper down have come unsprung ?

did you drain the tank after the layup and put new fuel in ?

just a couple of thoughts

Back in late '13, after an 18 month layup in my storage shed, my K-RS's fuel pump became noisy to the point of screaming when hot or on a longer ride. The fuel had turned nearly brown but did not smell too bad. I reckon it was the rubber breaking down due to some ethanol-laced petrol I had to use once or twice whilst travelling. I used the recommended dose of Sta-bil in the fuel during the sleepy time. But out on the road it nearly left me for dead in a threatening thunderstorm (that dropped record rains that night) in the rainforest up on the Great Dividing Range in NSW. The symptoms were that of cutting out like a rev limiter and incessant stumbling. I limped it home on a rainy arvo from Grafton to just south of Brissy next day after a night in a welcoming pub.

A year later when I returned home for another long ride, I brought a new pump and ancillaries along with me on the aeroplane and replaced it. 5000 kms later she hums like she should with nary a stutter or stammer.

Charlie, tank was empty bar a couple of litres on lay up. I'll check the damper clips once I've got the fuel level down a bit.

TWB my fear is that the pump just packs up and I do have a good spare but I've also read that it might be the pressure release valve kicking in due to kinked hoses. I've just replaced mine with FI appropriate hose but obviously not the proper shaped BMW ones. I'll check to see if there is a slight kink causing the problem.

mine grumbles and always has ...for at least 70,000 ...but then again I have taken a couple of topples
just recently I opened the tank again and found the clips had released ....has been a lot quieter just recently ...but as the fuel load gets down ...more noise is apparent ...that's why I thought to suggest it..  if your on a rs ..it might be harder to hear it  rt-lt  s tend to collect noise in behind that big wind breaker

good luck

Thanks Charlie, mines a 'naked' early k100. I'll post back once Ive done a bit more investigative work.

It seems that I upset my K100 with the replacement fuel hose I used. I made the return hose a couple of c/m longer to facilitate tank removal, this has caused a slight kink. When I press on the kink to effectively straighten the hose, the pump defaults to the usual low level hum.

sounds like your onto it ...

good luck

Cheers Charlie.

Well it seems that I was a little premature with regard to my screaming fuel pump and that pressing the hose was coincidental to the noise going.

I replaced my 'replacement' hoses with genuine articles and still got intermittent screaming, it seems worse when you rev and quieter on tick over.

So I drained the tank and checked the fuel filter against a brand new one I had. Whilst I could easily blow through the new one, the removed one took a bit more effort suggesting it was getting blocked. So I fitted the new one and the pump was immediately quieter with the odd screech. The filter I removed was only fitted 1500 miles ago so I thought maybe the rubber damper was breaking up (as has been suggested) but its intact with no flotsam in the coarse filter at the bottom of the pump. I'm now wondering excessively dirty petrol.........I tend to buy from the same source but the cars and other bikes have not suffered.

The pump is a lot quieter now but still does not seem as quiet as it used to be, although the screeching does seem to be diminishing. I do have another pump taken from a spare tank but I'll run the fitted one for a few miles to see if everything settles down. My fear is I've damaged the existing pump.

No drop in performance, suggesting its not the FPR, in fact the bike is running extremely well.

The screeching is often a sign of just plain and simple wear. The rollers in a roller cell pump do some amazing amount of work and last  a very long time. Eventually the rollers wear and then chatter as they revolve and screech is the exact term I would use to describe the noise.