On my K100RS all the stuff in the tank had turned to a rusted mess after sitting for 15 years with gas in the tank.This is how I found the bike.So,in 2017 I replaced everything in there and got it back in service.It had 12,000 miles on it at that point.A short 3 years and 10,000 miles later the new fuel pump started blowing it's fuse.I nursed it to home with a 10 A fuse but if I hit the gas hard that would blow too.Took it all apart and found the new pumps damper fell apart from the ethanol in the gas here in the US. I figured bits of it were being sucked into the pump causing it to draw more electricity to operate due to increased internal friction .So,I got 10,000 miles and 3 years out of a new pump because of crappy rubber that is used to make this part. What I plan on doing is finding a material that will do the job and last so I can make my own damper . I don't want to be doing this job every 3 years at the high cost of parts that we have to pay for crappy rubber that fails after 3 years and wrecks an expensive fuel pump.I'm thinking neoprene fuel hose like what large pipe connections are made of .

Do you store with E10 fuel in the tank? 

My first brick, a '94 K75RT, still has the pump and damper I bought it with.  That was 7 years and about 45,000 miles ago.  When it's going to be idle for more than a month I fill the tank with non-ethanol fuel and a shot of StaBil.  So far, the inside of the tank and the stuff in there still looks like it came from the factory.

I've owned my Brick for nine years or so. It came to me with a clean tank interior and a Mahle fuel filter dated 1996; the pump holder and damper were intact. I changed the fuel filter. I've used nothing but 89 octane E10 in it since then; those components are still clean. In each November, I put it up for six-months with a full tank of E10 laced with Sta-Bil and its fully-charged battery disconnected. It has always started easily and run well in spring. The fuel hasn't separated and nothing has gummed up. I ride it for 6,000 to 10,000 miles a year.

We can't get non ethanol fuel here in the NY metro area.It is not sold. The tank was like new after I cleaned it with acid and then washed it out a few times so the ethanol is to blame.We have had this garbage gas for 20 years now you'd think someone would be selling a damper made of something that doesn't fall apart when exposed to this crap. This is how clean I made the inside of the tank before putting in all new parts.
When I removed the replacement pump after 3 years the rubber was falling apart and bits of it were floating around in the fuel.

Pure-gas.org lists these guys as having non-ethanol gas in Huntington as of October 31, 2021.

Huntington

SUNOCO

Automotive Technology

631-923-1675

116 Spring Road

If I couldn't source non-ethanol, I would drain the tank before storage.  An empty tank does not have enough thermal mass to generate significant condensation.  Just run the engine with some Stabil to protect the fuel remaining in the lines, rail and injectors.

They list it but the greedy sob wants over 10 dollars a gallon so it really isn't an option.

Point-Seven-five wrote:Pure-gas.org lists these guys as having non-ethanol gas in Huntington as of October 31, 2021.

Huntington

SUNOCO

Automotive Technology

631-923-1675

116 Spring Road

If I couldn't source non-ethanol, I would drain the tank before storage.  An empty tank does not have enough thermal mass to generate significant condensation.  Just run the engine with some Stabil to protect the fuel remaining in the lines, rail and injectors.

I don't store my bikes.I have 6 on the road all insured ,registered ,and inspected and use them all year round .They are never off the road for more than a couple weeks at a time.We don't have the kind of winter you have upstate .Most of the time it's in the 40's with some 50's and when it's cold and snowy it only sticks around for a week to 10 days .

yamaguzzi wrote:The tank was like new after I cleaned it with acid and then washed it out a few times so the ethanol is to blame. 
I don't store my bikes.

It's difficult to understand why your experience with E10 would differ so much from mine.

One reason could be the sources of the fuel you're using. Another could be mileage combined with idleness. Suppose the total riding mileage of all your motos per year is 15000 miles. Divided among six motos that would be 2500 miles per moto. The length of idle time for Brick if it's the sixth moto in the riding cycle to be used could generate condensation in the tank. Bacteria could then go to work. A third cause could be the quality of replacement pumps and dampers.

Other than those, the cause could just be destiny.    I can understand your frustration. There seems to be a flaw in the durability of a Brick's pump mounting system, I just haven't encountered it. Maybe the rubber and composite parts in my moto's fuel tank were molded on a Wednesday. 

I put most of my mileage on the Moto Guzzi and the BMW with an even split.The 4 two strokes get limited use of about 800 to a thousand miles each due to the high cost of the synthetic 2 stroke injector oil I use in them and the fact that I have restored them to like new condition and want to keep them in that condition because of their value.So,the K100 gets around 4000 a year with a long trip up to Northern NY once a year and same for the MG 850-T .I run them both often . So,I guess it's wait and see time to see how long the rubber lasts of the aftermarket pump I bought from Euromotoelectrics . Maybe it was a bad batch of dampers or something like that but now I'm 6 months and around 3500 miles into the 2nd new pump so time will tell.

I'm thinking it's a bad rubber damper. I got cheap generic Chinese hydraulic hoses once, didn't even last two years. You would think the filter would stop the sticky rubber getting in the pump. 

Maybe the pump got rusty inside. When the warm air in the tank cools down condensation forms on the inner tank walls. Many short rides would make the problem worse. It's worse at a certain time of year too, here anyway. Keeping the tank full goes a long way to helping.

Service station tanks can crack and leak too, if you always get fuel from the same service station, that could be something to consider too. I knew a boilermaker who's full time job was repairing service station tanks. You could test the service station fuel and remove most of the ethanol at the same time too. Pour 10 litres into a clear container and check if any water settles to the bottom. Pour a litre of water in, shake it and relieve the pressure a few times. Allow it to settle. The ethanol is absorbed by the water, which reveals how much ethanol was blended in, you might only have say 9 litres of petrol left (and what looks like 2 litres of water) With a tap at the bottom you could drain the water out.

I made my own damper using polyurethane. Works fine .. 4 years and counting

Do you mind elaborating on that for some of us?
Thanks

Shep wrote:Do you mind elaborating on that for some of us?
Thanks

Sure. I actually made an adapter in order to fit a smaller diameter generic fuel pump ... a fraction of the price btw

https://bmwk100k75.weebly.com/fuel-pump.html

Let me know if you can't access the link

Nice work.  Thanks for posting that.

Thank you for the detailed information.

Kafflut wrote:

Shep wrote:Do you mind elaborating on that for some of us?
Thanks

Sure. I actually made an adapter in order to fit a smaller diameter generic fuel pump ... a fraction of the price btw

https://bmwk100k75.weebly.com/fuel-pump.html

Let me know if you can't access the link

Thanks , this is exactly the kind of information I am looking for.I love that you used the outer casing from the original fuel pump so it all fits right and you could use the screen on the bottom.I think that foam would help when the damper falls apart from the ethanol too as it will help filter the particles.