BMW Oilhead R850R R1100 Fuel Pressure Regulator Replacement Explanation (The Cheaty Way For Non-ABS)

This is not a full instructional video for this process as I don't have the resources to make one, but hopefully this clears up that it IS possible to change the Fuel Pressure Regulator on your early BMW Oilhead motorcycle without lifting the rear subframe, if you do not have an ABS unit installed on your bike.
I wasn't able to find any information on exactly how to do this and hopefully this video helps a bit if you can't find that info either.
Symptoms of a bad fuel pressure regulator, in my case, are a no-start condition with a working fuel pump and freshly rewired Hall Effect Sensor. Fuel pressure at the "send" line from the pump measures zero but when directed into a fuel container the fuel stream appears very strong. The bike runs on starting fluid. Fuel flow at the "return" line is very strong after several fuel pump cycles. Bike has strong spark both sides and the injectors both spray fuel when the bike is cranked but the spray has visibly low pressure behind it.
Here's a basic rundown of the process. These instructions apply for an R1100 or R850 R, and I believe will be similar for a GS. Other bikes with more fairings will of course require more steps. I do not know whether this applies to R1150 Oilheads as I have never worked on one, but because all of those came equipped with servo ABS the same restriction applies.
Remove the fuel tank and battery. (If you have the original single-throttle-cable arrangement instead of the updated multi-cable linkage underneath the battery box, your throttle cable steps will be different and you will not have to remove the linkage assembly. It will be easier for you to remove the battery box and you may not have to unhook the throttle cables at all.)
Unhook the throttle cables from both throttle bodies and unhook the choke cable from its lever. Push the choke cable down at the handlebar and pull it at the battery box so that you have a few inches of additional slack in the cable.
Unscrew the four screws holding the Motronic and its ground wire and mounting brackets to the battery box and let the Motronic rest on the front subframe. Remove the four nuts and washers on the floor of the battery box.
Lift the battery box and tip it to the left side of the bike; gently lift the retaining clip and slide the Bowden cable linkage unit out from the underside of the battery box.
Remove the E-clip holding the pivot block in and lift the block out. This will allow you to unhook the main throttle cable as well as the two cables going to the throttle bodies.
You can then let the battery box rest on the left side of the bike and this should give you access to the fuel distributor, which you can bend slightly upwards by hand to remove and install pressure regulator and its retaining clip. The clip is fairly easy to remove and comes out the right side of the distributor.
The pressure regulator is also held in by a pair of very tightly-fitting O-rings; to remove it you need to gently rock it back and forth while pulling it towards the handlebars. Be patient and don't flex the distributor too much while doing so and you will eventually get it out.
Lubricate the O-rings of the new pressure regulator with something safe for the fuel system (Vaseline or silicone oil is a good choice) and use the same careful process to put it back in.
As always, reassembly is essentially the reverse of these instructions. You will of course need to resynchronize your throttle bodies after this. Make sure you reattach the ground when you screw the Motronic back into its ears on the battery box!
Note: This only allows replacement of the regulator. It is not possible to replace the fuel distributor this way, as far as I can tell. If yours has a crack or break in any hard nylon parts, you will have to lift the rear subframe to replace it.
Hope this helps somebody out!

[@conhecereisaverdadeeaverda4365]

Muito bom seus vídeos

[@vincentvarela4522]

Thanks men very good explanation, I have the BMW 1995 R1100R 🏍️

[@missaellc1486]

This will not be a easy work for my R1150RT because de ABS module. Thanks for the info. I broke the oem fuel pump, but the replacement I used, just failed, and I want to replace it with filter fuel pump and the pressure regulator

[@magicoddeffect]

Bikes like yours are, I think, the reason the manual recommends transmission removal -- your servo ABS unit is very difficult to reinstall.

[@mmm4638]

Thanks

[@srenisager6686]

Hello. can you tell if the fuel pump suppose to run all the time when engine is on /Running. Mine does.

[@magicoddeffect]

Yep, when the engine is running the fuel pump is constant.

[@var3nka]

So did it work?

[@magicoddeffect]

In a roundabout way, yes. After changing the regulator I soon figured out that my almost-brand-new fuel pump had gone bad. So the replacement might have been unnecessary, but it did help me find the real issue soon after, and it was a good idea to replace the 20+ year old original part regardless. If you have fuel pressure problems and have a known working fuel pump and filter (tested with a fuel pressure gauge) and known good fuel injectors and fuel lines then the pressure regulator is likely what needs replacement. I'd still recommend that the original FPR be replaced on any bike this age since it has rubber parts and touches gasoline.

[@var3nka]

@@magicoddeffect I've replaced the fuel tank and pump, as well as the injectors. Here's hoping the regulator does the trick... '96 R850R

[@magicoddeffect]

@@var3nka You should do a fuel injector spray test -- you can visibly see if they're getting too little pressure by pulling one out and aiming it at a piece of cardboard while cranking the bike over a few times. If you get drips rather than a spray, then you have insufficient fuel pressure. If you have no fuel spray at all, or missing spark, you likely have a bad crank position sensor, aka Hall Effect Sensor. Every single original one on these bikes goes bad and needs to be repaired or replaced.

[@davidcosine]

​@magicoddeffect good comment doing this now on 97 r850r... tank off after bike cut out after one tank gas post clutch replacement. Fuel filthy. Guessing it was fuel filter but now I'm thinking replace pump while tank off.