37mm pump in K1200RS?

[AntonLargiader]

I need to replace a K12RS fuel pump and I'm looking for alternatives. I know EME has a 43mm pump for sale but it's way too loud. 37mm pumps (like the R1150R and all later bikes use) are nice and quiet and readily available. Anyone have a good way of mounting one? Seems pretty straightforward to fabricate a set of mounting rings to make the 37mm pump take up the space of a 43mm pump.

 

[GTRider]

Are the pumps the same length? I sold my ‘04 K12GT a couple years ago, but IIRC the rubber dampers cupped the upper and lower ends of the pump and had to be compressed downward, along the length of the pump, to fit the retaining clip. If the lengths match, then yes—it shouldn’t take much work on a lathe to spin out a couple of spacer rings or even a split sleeve to take up the 6mm difference.

Best,
DeVern

 

[AntonLargiader]

76mm vs. 98mm length of the cylindrical body. I'd want the bottom to be as close as possible so the sock filter still fits, so there would be a fairly long upper sleeve that makes up the length. It's long enough that the hose will have to be fastened to the pump before that sleeve goes into place.

FWIW the new pumps are 38mm, not 37mm. If I could find some 33mm ID, 43mm OD plastic pipe I'd have a super easy time of this!

 

[omega man]

76mm vs. 98mm length of the cylindrical body. I'd want the bottom to be as close as possible so the sock filter still fits, so there would be a fairly long upper sleeve that makes up the length. It's long enough that the hose will have to be fastened to the pump before that sleeve goes into place.

FWIW the new pumps are 38mm, not 37mm. If I could find some 33mm ID, 43mm OD plastic pipe I'd have a super easy time of this!

It wouldn’t have to be just plastic pipe. Many times the fittings for plastic pipe or accessory drains like a P-Trap sink drain plastics come real close.
Plastic components “turn” real easy on a lathe.
Good luck.
OM

 

[oldcamper]

I need to replace a K12RS fuel pump and I'm looking for alternatives. I know EME has a 43mm pump for sale but it's way too loud. 37mm pumps (like the R1150R and all later bikes use) are nice and quiet and readily available. Anyone have a good way of mounting one? Seems pretty straightforward to fabricate a set of mounting rings to make the 37mm pump take up the space of a 43mm pump.

There are a number of $40 pumps on eBay that claim to fit a k12rs.

Fuel Pump For BMW K75 K100 K1100 K1200 R100 R1100 R1200 1996-2004 | eBay

OSIAS Fuel Pump For BMW K75 K100 K1100 K1200 R100 R1100 R1200 16141464730. 2003-2005 BMW R1200 Montauk. Fuel Pump Assembly. Motorcycle Fuel Pump. High Pressure Fuel Pump. Fuel Pump Strainers. 2004 BMW K1200GT through 10/04.

www.ebay.com

I have no idea on the diameter or noise level but did install similar in an f650 scarver a couple of years ago and it worked well. These pumps seem pretty generic and I think are used in many applications.

 

[kinterridge]

I've attached a nominal pipe conversion mm to inch chart. Your 33mm id and 43 od are not standard pipe sizes, at least in the plumbing world. You may find a size close for cutting to size though. The non-pdf chart is for schedule 80 PVC, I think the 1-1/4 would be the size to turn down.

Size (in.)	Wall Thickness (in.)	Outer Diameter (in.)
1	0.179	1.315
1 1/4	0.191	1.660
1 1/2	0.200	1.900
2	0.218	2.375

 

[PGlaves]

Wondering. Is PVC impervious to gasoline and ethanol if submerged for prolonged periods of time?

 

[98lee]

I need to replace a K12RS fuel pump and I'm looking for alternatives. I know EME has a 43mm pump for sale but it's way too loud. 37mm pumps (like the R1150R and all later bikes use) are nice and quiet and readily available. Anyone have a good way of mounting one? Seems pretty straightforward to fabricate a set of mounting rings to make the 37mm pump take up the space of a 43mm pump.

Anton,

I would give highflo a try.

https://www.highflowfuel.com/?gad_s...cSpoKuzglelo4xT937Ahi12uyC583ta4aAqE0EALw_wcB

Their Quantum series pumps have a LIFETIME guarantee!!! I’ve just started using them and, so far, very impressed with the quality, variety, price, and service. They are based in Ventura CA (Los Angeles).

 

[pauls1150]

I just googled "is PVC impervious to gasoline" and the answers are all over the place...

 

[omega man]

I use Delrin for a number of odd repairs. Acetal is sorta a cousin-

Wide Selection of Acetal/Delrin Tube Cut-to-Size and In Stock

Wide Selection of Acetal/Delrin Tube Cut-to-Size and In Stock. Fast Shipping and Easy Online Ordering. Trusted for Over 100 Years.

www.eplastics.com

Strong, easy to turn, form, shape and all but indestructible even when used as a punch. Usually you need an industrial supply house to purchase.

OM

 

[GTRider]

McMaster-Carr carries Delrin pipe/tubing.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Best,
DeVern

 

[kinterridge]

Wondering. Is PVC impervious to gasoline and ethanol if submerged for prolonged periods of time

Leaded and unleaded gas, yes up to 140 degrees F. I would not use it. it may swell. See attached pdf.

 

[kinterridge]

I think the best tubing material to use would be HDPE (hi-density poly ethylene). That's what they use in plastic fuel tanks for vehicles, like Mopar used for years. HDPE piping is used in a lot of underground boring jobs by utilities because it is fused together by heat, making a continuous runs with out mechanical couplings. For water, sewer, natural gas, etc.

 

[AntonLargiader]

I would give highflo a try.

Are any of them drop-in size replacements for the 43mm pump? And how loud are they? I'm thinking that I want to settle on two approaches:
- drop-in replacement using existing BMW mounts
- make adapters for the 37mm pump that the later BMWs use

This way the bike can be repaired in the future using BMW-spec parts. I don't want owners, future owners, or other shops to have to figure stuff out all over again.

The K12 is actually easy for adapting the 37mm pump to, because that pump (or nearly any cylindrical pump) can be clamped to the curved frame of the pump assembly. The R1100 bikes are different, though. They really want the pump and mounts to fit into a certain bracket configuration.

 

[98lee]

Anton,

They say they are drop in replacements, but they might be 37mm with a sleeve (provided). They say they are designed to be as quiet or quieter than stock. My 52mm pump from them is very quiet.

In looking at the pictures for the pump for the K12RS, the strainer sock is different than the stock BMW one. The lifetime warranty is an added plus. You can get just the pump and strainer or kits that include everything including regulator, tank opening gasket, hoses, filter, or anything in between.