2000 r1100R losing power on the road

[Bob D NC]

HI - working on a friend's bike that sat for many years after an electrical short (the ground - brown - wire from the fuel tank still has some insulation issue along its route - from the bike connection). The bike would not run. I replaced the fuel pump, filter, and rewired the fuel tank harness from the tank to the bike connector. The bike runs now, but not well. It cannot maintain RPM above 4000... it loses power and slowly drops below 3000 and then may stablilze... or, if I flick the throttle, it may climb in power... only to fade again. I can keep it running, but it is not really rideable.

 

I disconnected the cannister and O2 sensor with no change to performance.

 

It acts as if there is a fuel supply problem... losing pressure? bad new pump? bad regulator? Thoughts... and thanks!

 

 

[dirtrider]

1 hour ago, Bob D NC said:

HI - working on a friend's bike that sat for many years after an electrical short (the ground - brown - wire from the fuel tank still has some insulation issue along its route - from the bike connection). The bike would not run. I replaced the fuel pump, filter, and rewired the fuel tank harness from the tank to the bike connector. The bike runs now, but not well. It cannot maintain RPM above 4000... it loses power and slowly drops below 3000 and then may stablilze... or, if I flick the throttle, it may climb in power... only to fade again. I can keep it running, but it is not really rideable.

 

I disconnected the cannister and O2 sensor with no change to performance.

 

It acts as if there is a fuel supply problem... losing pressure? bad new pump? bad regulator? Thoughts... and thanks!

 

 

Afternoon Bob D NC

 

Could be a problem with the "U" shaped hose inside the fuel tank.  (usually small split or pin hole)

 

You should probably start by  running  a fuel return hose flow test. (see how much fuel you are getting out of the fuel return hose coming from the rear).

 

That will tell IF you are getting enough fuel flow at enough pressure to run that motorcycle correctly. (you need to see  a pencil size stream of fuel coming from the rear  return hose for about 2 seconds at key-on then a continuous flow during engine cranking)  

 

On the 1100 bikes, if it has been updated to have fuel line quick disconnects, then don't forget to hold the rear quick disconnect inner check valve open or you will get no fuel flow. 

 

If the flow isn't up to par then run a voltage drop test on the fuel pump (B+) & (-) side wiring (between pump connector & battery posts). 

 

If the voltage drop is OK then look for pressure side leakage inside the tank (usually that darn U hose).

 

If the fuel pump passes muster then possibly partially blocked fuel injectors or even a partially plugged exhaust (look for muffler inner baffle rusted & dropped down or cat converter partially plugged. (try running it with rear exhaust removed) 

 

Or look for intake blockage (junk in the  air filter box or plugged air filter  (try running it with air filter removed). 

 

Added: Being an 1100 you might also want to verify the wiring on the HES  (Hall Effect Sensor) that is a known problem area on the 1100 (Ma 2.2). Usually doesn't cause the kind of problem that you are seeing but under the right failure circumstances  (circuit cross-talk) I suppose it could.    

[Bob D NC]

I did replace the u-shaped hose with the flex line I got with the fuel pump (from beemerboneyard), but now I wonder if I cut it too short and perhaps the bend is too tight. I had cut it longer too start but then it seemed to interfere with the float. So I shortened it so the float would clear it. I will do a flow check in the morning.

[Bob D NC]

Fuel flow appears to be adequate... but that does not mean the pressure is good. I am going to purchase a fuel pressure testing set to verify the pressure.

 

Is there a recommended procedure for cleaning the injectors? ... or are they a replacement item?

 

THanks!

[dirtrider]

17 minutes ago, Bob D NC said:

Fuel flow appears to be adequate... but that does not mean the pressure is good. I am going to purchase a fuel pressure testing set to verify the pressure.

 

Is there a recommended procedure for cleaning the injectors? ... or are they a replacement item?

 

THanks!

Morning  Bob D NC

 

Actually if RETURN flow is good then that means pressure is good as the pressure needs to be high enough to open the pressure regulator & allow fuel return flow. If fuel pressure is too low then the pressure regulator will not allow fuel return flow (it will just deadhead at pressure regulator) 

 

This is the nice thing about a fuel return flow test, it tests BOTH pressure & flow.  

 

Next, you might want to look in the top of your fuel injector fuel inlets, there are very fine screens in the inlet that if partially plugged can restrict fuel flow. 

[Jim Moore]

A fuel issue is usually indicated by violent jerking and surging. It's very distinct. 

 

I had a similar issue once. I was convinced it was fuel. Turned out to be a bad ignition timer, AKA Hall Effect Sensor, AKA HES. Erratic rpm indications are a reliable symptom. If you haven't replaced or rewired the HES on that bike you need to do it anyway (it's on its way to failing), so this is a good a time as any.

[Michaelr11]

1 hour ago, Bob D NC said:

Is there a recommended procedure for cleaning the injectors? ... or are they a replacement item?

 

There are videos for DIY injector cleaning.  But, for not much money, pull them out and send them to a professional injector cleaning company.  They will put on new orings and filters, flow test before and after cleaning.  I paid $18 per injector plus shipping there and back - cost me about $54.  Figure a couple of weeks altogether.  I used Injector Rx in TX.  Maybe there is a service local to you.

[Lowndes]

Bob,

 

Injector Rehab in Blackwood, NJ, has been very good to deal with.  Keith Gibbons is the owner and good guy.

 

The website has write-ups on their test setup and what they do.  

 

https://injector-rehab.com/knowledge-base/dynamic-testing-and-cleaning-fuel-injectors/

 

A Youtube vid of "Upgraded BMW R1100GS and 1150GS - R1200 Fuel Injectors" with spray patterns at Injector Rehab:

 

https://www.youtube.com/watch?v=PiX6CEZhNcg

 

They sell new and refurb injectors with flow charts, plus all the spacers, adapters, O-rings, filters, etc.

 

Here are some pics of the '99 R1100RT OEM yellow tipped injectors being replaced by the newer 4 hole EV14 Bosch injectors with brass-color annodized adapters:

 

https://goo.gl/photos/oQ8BBhTRRHQHPW5B7

 

These are the injector inlet filters Dirtrider was referring to: 

 

 

They sit flush in the inlet of the injector like this and are best removed with a drywall screw:

 

 

That's an OEM filter on the left that's been removed:

 

 

 

[Bob D NC]

Thanks for the input so far… I did check the wrong line for return flow… so my updated situation is:

 

furl pressure is only 32 psi (I verified gauge accuracy) and there is zero flow on the return side.

 

so I am thinking bad (although new pump) or I linked or cracked the u shaped hose. (Filter is new.)

[dirtrider]

20 minutes ago, Bob D NC said:

Thanks for the input so far… I did check the wrong line for return flow… so my updated situation is:

 

furl pressure is only 32 psi (I verified gauge accuracy) and there is zero flow on the return side.

 

so I am thinking bad (although new pump) or I linked or cracked the u shaped hose. (Filter is new.)

Afternoon  Bob D NC

 

Yes, sounds like something inside the tank (or low pump supply voltage). Are you using the correct high pressure hose clamps inside the tank? Standard worm gear type clamps are usually a problem (if not now then for sure later)

 

It doesn't take much of a leak in the high pressure circuit inside the tank to bleed off pressure.

 

Even with a kinked hose if it runs then it should eventually make enough pressure to open the regulator return valve with engine not running as it isn't using any of the flow when not running. 

 

Also, with all the wire damage you had  be sure to run a voltage drop test on the pump wiring all the way back to the battery (+) & (-) posts.

 

If low pump supply voltage then it probably won't make good pressure.    

[Bob D NC]

I am using high pressure clamps (from boneyard). I was wondering about the voltage ‘supply’. I assume I should have a 12 volt  drop everywhere in the circuit?

[dirtrider]

2 hours ago, Bob D NC said:

I am using high pressure clamps (from boneyard). I was wondering about the voltage ‘supply’. I assume I should have a 12 volt  drop everywhere in the circuit?

Afternoon  Bob D NC

 

No, you want to see as close to 0 volt drop as possible on the voltage drop, if you see 12v then you have very/very high resistance in that circuit. (with voltage drop test you are basically measuring the resistance under load) 

 

Caution: do not run that pump outside of the tank for more than a nano second as those pumps are fuel cooled & fuel lubricated so can burn up quickly if not submerged in fuel)

 

In the picture below if the wires carry all the load then the voltmeter will show no voltage drop. 

 

If the wires have resistance, bad connection, etc then the voltmeter will carry all or part of the load so will show voltage, can show as high as the full battery voltage. You want to see almost no (or very low) voltage on the meter as that means that the wiring is carrying all the load. Test one side (positive then test negative side)  of the circuit at a time so you can use one meter for the testing. 

 

[Lowndes]

1 hour ago, Bob D NC said:

I am using high pressure clamps (from boneyard)...

 

Bob,

 

In case the voltage drop is not your problem:

 

(And don't forget to check the "ground" side of the circuit)

 

If you are using these clamps from BBY, they are subject to not being quite tight enough.  AMHIK.  

 

 

The best clamps are the Oetiker type that "crimp" onto the hose with a special tool.  With the correct sized barbed tube, rubber tube, and clamp, you get a proper seal that does not leak.  I learned this the hard way.  $25 for a kit is cheap compared to being on the side of the road far from home with a dead bike and a bunch of riding buddies standing around!!

 

This is one of many kits available:  https://www.amazon.com/dp/B08P5S9TWV/ref=sspa_dk_detail_5?psc=1&pd_rd_i=B08P5S9TWV&pd_rd_w=mLnoW&pf_rd_p=887084a2-5c34-4113-a4f8-b7947847c308&pd_rd_wg=TBxNf&pf_rd_r=744JNMD3CA8RCDCGKMVF&pd_rd_r=07c7373f-3002-4dc4-8933-e984a5a77598&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFVU0g5WEszQ01SOTYmZW5jcnlwdGVkSWQ9QTA2ODI1MjcyQ0YyWUtHS1EyNFRTJmVuY3J5cHRlZEFkSWQ9QTAxNTk2NTIySkZOSzFWQzY5NzE0JndpZGdldE5hbWU9c3BfZGV0YWlsJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

 

 

 

[Bob D NC]

Ok… thanks for the really good advice on my fuel supply issue. I ended up using bits and pieces of everyone’s suggestions to find the problem. When I was unable to find a voltage drop problem I tore into the tank again and found the short straight line to the filter was allowing fuel to bypass under the clamp. I used a longer hose and a better clamp and now the fuel pressure is where it needs to be. Bike is running great now.

 

Thanks to all again.👍

[dirtrider]

1 hour ago, Bob D NC said:

Ok… thanks for the really good advice on my fuel supply issue. I ended up using bits and pieces of everyone’s suggestions to find the problem. When I was unable to find a voltage drop problem I tore into the tank again and found the short straight line to the filter was allowing fuel to bypass under the clamp. I used a longer hose and a better clamp and now the fuel pressure is where it needs to be. Bike is running great now.

 

Thanks to all again.👍

Evening Bob

 

Glad you have the problem identified & repaired. Did you use a proper SAE 30R10 (or equivalent) rated high pressure fully fuel-submersible hose? If not then it will probably come back to haunt you at a later time.

 

 

[Bob D NC]

Yep…definitely used the submersible in fuel hose. 👍