Arsebiscuits!! Here we go again, another chapter

Bill,

When you say that it ran fine for ten minutes, was that riding it (ie mixed throttle openings) or just left running at a fast idle?

Without going back through all of the threads on the problem, when were the throttle cables last replaced?

I ask as when a mate was running an 1100GS, he had something similar; the bike would run on two cylinders and then drop to one. It was as though the cable wasn't seated correctly at the throttle-end (you know the photo well).

Yet whenever they were checked, both were seat correctly. In fact what was happening is that one cable had frayed inside the outer sleeve. It would stick and throw the balance right-out.

I found out by feeling for the slack in the exposed section of the cable (with the throttle closed) between the adjuster and the quadrant-guide.

Try opening the quadrants with your delicate little fingers and check that they both snap-shut repeatedly against the stops.


They do Mike......the cables were last changed in the last 6 months (well, one was, the others were all examined while the Bowden box was out, lubricated then tucked away again.

It ran well for ten minutes on the road...full acceleration, all gears.

The tank has been off and on 3 or 4 times over the last few weeks........all the vents are cleared, the internal wiring is fine and fresh and the pump is new.

I've even replaced the 4 pin multi plug for the tank supply with two x 2 pin watertight plugs.

The pump primes fine.

When I replaced the very short connector tube that had been ballooning out 'twixt the pump and metal rail spigot, I put in PTFE reinforced tube....and replaced all the rest of the internal tubing as well.

The splitter/regulator is the only part I haven't opened up or replaced.

A physical blockage (paint from tank or some shit from it being dry for a while) fits the profile, and as I had all the tubing out/off and blew it with an airline, it could easily have opened up the blockage, which after 10 minutes of running, then popped back to whatever the narrowest point in the splitter area is.

I'll get there..........in the end :rolleyes:
 
The external fuel filter (below) is clean (you can take it apart completely and wash the little brass filter in it)
Is that fine enough for the FI system? Just wondered if some tiny particle had got through to injector and is partially blocking it?
 
just a thought I was a complete arse recently, in that when I put the tank back together I got the whole pump assembley one bolt further round than it should be, as a result the tank was half full of petrol the pump could not get at. It may be worth a check.
 
if the problem is on only one cylinder that sounds to me like its electrical in nature,got lots of bits if you ya want to try swapping parts you are more than welcome,recently broken one,borrow what you want no problem,Cheers E7 london
 
First thought is that 30 micron is pretty coarse. Is it quoted as "30 Micron absolute" ? If not it just means that it will stop some particles at 30 micron. I've had a very quick look at a fuel filter spec. document and some filters are rated down to 2 micron absolute, stops ~98% of 2 micron particles.

I would put a standard filter back in line and clean everything downstream of the filter. The trouble is that you can barely see individual particles at 30 micron so getting everything clean is difficult. Perhaps send the components to a fuel injection specialist for cleaning and testing then re-install.

Your current filter may be perfect as a pre-filter to stop coarse sand and crap blocking the main filter when playing in Maroc.
 
I would put a standard filter back in line and clean everything downstream of the filter. The trouble is that you can barely see individual particles at 30 micron so getting everything clean is difficult.

Exactly, that's why in the first thread of this saga an injector was changed and it ran well for a while.
It was suggested several months ago where the problem lay:blast
 
I thought stuff bigger than 30 microns would not fit through the filler cap, I would get hold of a proper FI filter, repeatedly getting the injectors cleaned is a very expensive way of cleaning out the fuel system.
 
Exactly, that's why in the first thread of this saga an injector was changed and it ran well for a while.
It was suggested several months ago where the problem lay:blast

Which is why I did it......the pump has been changed, the filter several times (ending up with this 30 micron aluminium jobby) and everything else apart from the pressure regulator has been changed.....other problems have also got in the way of a 100% diagnosis (dead starter motor, ballooning fuel pipe in tank, unable to get TBs balanced etc etc)

The non-firing can be switched side to side by swapping the injectors over.

I'm looking for a replacement now :P

And OK, I'll get a BMW OEM filter as well........the amount of times I've had the tank on and off, I reckon I can replace one internally in ten minutes flat now :blast

BTW, the BMW part number for the injectors is 13 71 1 342 366, but I've tracked that down to being a Bosch BOINJ-R366.

EDIT......for reference, the flow rate is 339 cc's / minute, but I cant see that being totally critical as the same injector is fitted to many BM's, including the 650 GS , montauk, RT etc

I'm keeping my fingers crossed that another vehicle uses that type, or I can match another injector, as I now know the flow rate and other parameters :thumb

Yet another EDIT........I'm having a hard time understanding the immense differences between prices and the types of FI units.....

As long as the flow capacity is OK, surely an injector is just a mini solenoid type device with a plunger, activated by the FI signal (which I know I have 'cos I had a noid light in the socket)

The length isn't critical, as our injectors are 'out there' and there's plenty of movement available in the cabling and tubing to them......and the end types/o ring seating seems to be fairly common as well :nenau

I'm getting really frustrated by the fact that a very similar looking injector for some poxy little car (with a similar displacement per cylinder) is £25, yet the Bosch/BMW units are a fekking fortune :mad:

What's to stop a FI unit with a similar flow rate and resistance parameters from being used :nenau
 
Hi Fanum :comfort
Had a similar starting problem on my mate 1150 a few years back. Pulled the starter motor apart and there is a metal dust shield at the drive end that had come adrift and was shorting out the windings, so I removed it. It was sorted properly when we got back home a few days later.

Hope it helps. :bounce1

Scuba

My 1150 suffered the same problem with the starter. The dust cover ended up with holes burnt in it where it was contacting the windings :blast:blast
 
BTW, the BMW part number for the injectors is 13 71 1 342 366, but I've tracked that down to being a Bosch BOINJ-R366.

EDIT......for reference, the flow rate is 339 cc's / minute, but I cant see that being totally critical as the same injector is fitted to many BM's, including the 650 GS , montauk, RT etc

I'm keeping my fingers crossed that another vehicle uses that type, or I can match another injector, as I now know the flow rate and other parameters :thumb

Yet another EDIT........I'm having a hard time understanding the immense differences between prices and the types of FI units.....

As long as the flow capacity is OK, surely an injector is just a mini solenoid type device with a plunger, activated by the FI signal (which I know I have 'cos I had a noid light in the socket)

The length isn't critical, as our injectors are 'out there' and there's plenty of movement available in the cabling and tubing to them......and the end types/o ring seating seems to be fairly common as well :nenau

I'm getting really frustrated by the fact that a very similar looking injector for some poxy little car (with a similar displacement per cylinder) is £25, yet the Bosch/BMW units are a fekking fortune :mad:

What's to stop a FI unit with a similar flow rate and resistance parameters from being used :nenau

From the little I know:

The pulse width to the injector, together with flow rate, determines how much fuel goes in therefore mixture. Closed loop (when the engine management is running from the lambda sensor), pulse width can be adjusted to get correct mixture (up to the limit placed by the flow rate as the pulse width approaches maximum duty cycle i.e. it's on for as much of the inlet stroke as it can be). Open loop, mixture is based on a map of pre-determined pulse widths for engine speed, throttle opening (mass air flow, but I don't think our bikes have a sensor for that) etc. The lambda doesn't react fast enough to run closed-loop e.g. when accelerating hard, so flow rate is important for correct fuelling.

Maybe a grown-up will be along shortly to explain how much leeway the system has?
 
BTW, the BMW part number for the injectors is 13 71 1 342 366, but I've tracked that down to being a Bosch BOINJ-R366.

EDIT......for reference, the flow rate is 339 cc's / minute, but I cant see that being totally critical as the same injector is fitted to many BM's, including the 650 GS , montauk, RT etc

I'm keeping my fingers crossed that another vehicle uses that type, or I can match another injector, as I now know the flow rate and other parameters :thumb

Yet another EDIT........I'm having a hard time understanding the immense differences between prices and the types of FI units.....

As long as the flow capacity is OK, surely an injector is just a mini solenoid type device with a plunger, activated by the FI signal (which I know I have 'cos I had a noid light in the socket)

The length isn't critical, as our injectors are 'out there' and there's plenty of movement available in the cabling and tubing to them......and the end types/o ring seating seems to be fairly common as well :nenau

I'm getting really frustrated by the fact that a very similar looking injector for some poxy little car (with a similar displacement per cylinder) is £25, yet the Bosch/BMW units are a fekking fortune :mad:

What's to stop a FI unit with a similar flow rate and resistance parameters from being used :nenau

From the little I know:

The pulse width to the injector, together with flow rate, determines how much fuel goes in therefore mixture. Closed loop (when the engine management is running from the lambda sensor), pulse width can be adjusted to get correct mixture (up to the limit placed by the flow rate as the pulse width approaches maximum duty cycle i.e. it's on for as much of the inlet stroke as it can be). Open loop, mixture is based on a map of pre-determined pulse widths for engine speed, throttle opening (mass air flow, but I don't think our bikes have a sensor for that) etc. The lambda doesn't react fast enough to run closed-loop e.g. when accelerating hard, so flow rate is important for correct fuelling.

Maybe a grown-up will be along shortly to explain how much leeway the system has?
 
......And OK, I'll get a BMW OEM filter as well........the amount of times I've had the tank on and off, I reckon I can replace one internally in ten minutes flat now :blast

It doesn't have to be genuine BMW part or inside the tank, as long as it is in the main supply line and a lot finer than the collander that you're curently using.

Re the injectors, I'd expect that all manner of factors would be relevent including response time, mass of the moving parts etc. Bite the bullet and fit the genuine article. Once it's running perfectly you can play with other injectors.
 


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