Another step forwards in solving the problem...now, Lambda sensors info please?

[(RIP) DitchWater]

I wish you luck with your lambda sensor because when my bike was having its last episode of fuelling problems some Geezer decided that my lambda sensor was flat lining and replaced it with one from BMW. He told me to go away, ride and get back to him, which I did.
The GS911 goes back upon my return and the new lambda sensor is showing a flat line and he's thrown the old one away.

The parts on my bike which were swapped or replaced to try and identify the problem were TPS, fuel injectors, coils sticks, lambda sensor, LHS intake manifold, air intake sensor, Hall sensors and battery. The problem was NOT resolved.

Eventually I purchased a second hand set of throttle bodies and decided to try them and found a significant improvement straight away. It's not perfect when balancing but much better. I'm going to have a pair of my throttle bodies serviced because the rattle is very noticeable and when manually damping the throttle cable drive at idle speed the balance changes.

It would appear that there's a lot to check and test.

 

[warmshed]

I agree, large clearance will not affect the compression. I suggest either the vaves were not returning fully, carbon on the seats?? or valve sticking.

If the colletts were loose then you should not have been adjusting the clearance you should be removing the head and checking the springs its the only thing that could cause that.

With that much change in the clearance then again you should be looking for the reason not adjusting them,

 

[Steptoe]

Resetting the valve clearances would not improve the cylinder compression by that much.

Wear in the valve train is the only thing that would cause the valve clearances to increase by a huge amount. If something in the valve train has lost its surface hardness you will find that the valve clearance will keep increasing until you run out of adjustment.

Has it been 'sorted' though mate? The valve clearance should have only altered by a few thou, if at all.

Can't understand how tightening the valve clearances raises the compression - doesn't make sense Could it be a sticking valve/s? I hope you get it sorted - it's the sort of thing that could drive a man to drink

That's a new one to me

Would removing Fuse 4 or 5 (can't remember the exact one) help clearing out the memory of the ECU incase it's caught in some sort of loop ?





Doesn't make a lot of logical sense that ?

plugs out, air has an easy path into cyclinder, fit compression guage, turn engine over see what the guage goes to ?

I'd have thought even if the intake valve only opened a fraction it would be enough to suck in the correct amount of air or you'd see the compression guage going negative/decreasing as a vacuum was created before the compression went positive ??

I agree, large clearance will not affect the compression. I suggest either the vaves were not returning fully, carbon on the seats?? or valve sticking.

If the colletts were loose then you should not have been adjusting the clearance you should be removing the head and checking the springs its the only thing that could cause that.

With that much change in the clearance then again you should be looking for the reason not adjusting them,

The valve clearences were .95 on the exhaust and around .75 on the inlet.

6.6ish bar compression before adjusting - 12 bar after adjusting.


I've said to Bill i suspect the throttle bodies are the main suspect in being unable to balance them.

But, and a big but...... why did it previously run perfect for 60-80 miles after changing the injector, and then went back to running rough again.

 

[Steptoe]

Would removing Fuse 4 or 5 (can't remember the exact one) help clearing out the memory of the ECU incase it's caught in some sort of loop ?

Pulling fuse 5 clears the ecu of the throttle range, fully open to fully closed. Nothing more nothing less.
You don't even need to reset it, the bike will do it in a couple of minutes as you ride.

 

[ChrisH Kerry]

I'd have the head off and valves out to see what's going on - if the valves are sometimes not closing properly that would affect the depression at the throttle body ... no? There must be a reason for the discrepancy in valve clearance measurements....

 

[Steptoe]

I'd have the head off and valves out to see what's going on - if the valves are sometimes not closing properly that would affect the depression at the throttle body ... no? There must be a reason for the discrepancy in valve clearance measurements....

New heads barrel and pistons fitted after the originals destroyed themselves through a dropped valve. All perfect before assembly.

And all other mechanical items in the engine ok prior to reassembly.

I suspect throttle bodies or something electrical. because the bike ran perfectly for 60-80 miles after fitting a new injector. Perhaps something electrical was disturbed ?

Anyway, as is the way with diagnosing these types of problems. One thing at a time.

 

[Shep]

A sticking throttle body might explain the low compression and rough running, if it were randomly sticking shut then atmospheric pressure may not be able to fill the cylinder completly in the time allowed?

It won't explain the valve clearances though?

 

[DrFarkoff]

The valve clearences were .95 on the exhaust and around .75 on the inlet.

Hey Steppers do we take it that Fanny wears ear protection and an I pod and and and

Fuck me surely you'd have heard those buggers knocking??

 

[Shep]

Hey Steppers do we take it that Fanny wears ear protection and an I pod and and and

Fuck me surely you'd have heard those buggers knocking??

I think you need an element of mechanical sympathy to hear that sort of thing, i've never heard of Fanny ever being accused of having mechanical sympathy

 

[MattW]

2p from me.

Before I had the TB's rebushed on my 1100, it was impossible to achieve a good balance - I assume general sloppiness and air leaks through the butterfly shafts was the cause. After the TB's had been done, it balanced fine (or at least as fine as the daft single piece cable allows ).

Huge increase in valve clearances? My guess would be camshaft / rocker wear (or something else in the valve train - cam bearings?) - can't see it being anything else really that would affect both intake valves at the same time.

I'd have the head off and have a look - I'd also want to take a look at the bore after prolonged running on one cylinder (know anyone with a boroscope?) - fuel washing can cause problems with bore wear (although the BMW nickasil is probably more resistant to this than iron liners).

Good running for 80 miles then back to rough again after an injector change? No bloody idea (unless in-spec fuelling caused to lambda to behave temporarily ). I'd hope your lambda change might iron this one out.

All IMHO etc, etc

Good luck with it Bill - hope you get to the bottom of it.

 

[Steptoe]

A sticking throttle body might explain the low compression and rough running, if it were randomly sticking shut then atmospheric pressure may not be able to fill the cylinder completly in the time allowed?

It won't explain the valve clearances though?

There are other things on fannys bike that may be contributing to these problems - the R/H throttle cable is too short and has to have the locking nut underneth the locating tab on the body instead of on top just so you can get a thou of slack in the cable .

So it could be the throttle cable cassette is fecked ?.

Lets go back to the beginning - Chad and Maverick did a lot of work on the bike for Bill after it had stood for a long period of time, i think others may also have "helped".
One of the jobs undertaken amongst all the other work was removing the alarm after the bike wouldn't start.
Now, just after all this work was done the bike dropped a valve...........

So, you can see this has great potential and everyones opinion on what the problem is/was/could be, is very admirable but as this bike isn't normal and was worked on by several enthusiatic amateurs all at the same time (no doubt all sharing the same spanner) gives us unlimited scope...

 

[Steptoe]

2p from me.

Before I had the TB's rebushed on my 1100, it was impossible to achieve a good balance -.

Believe me this is more than just "out of balance". And it isn't constant through the rev range.

 

[JohnnyBoxer]

There are other things on fannys bike that may be contributing to these problems - the R/H throttle cable is too short and has to have the locking nut underneth the locating tab on the body instead of on top just so you can get a thou of slack in the cable .

So it could be the throttle cable cassette is fecked ?.

Lets go back to the beginning - Chad and Maverick did a lot of work on the bike for Bill after it had stood for a long period of time, i think others may also have "helped".
One of the jobs undertaken amongst all the other work was removing the alarm after the bike wouldn't start.
Now, just after all this work was done the bike dropped a valve...........

So, you can see this has great potential and everyones opinion on what the problem is/was/could be, is very admirable but as this bike isn't normal and was worked on by several enthusiatic amateurs all at the same time (no doubt all sharing the same spanner) gives us unlimited scope...

I'm sure you'll get to the bottom of it, we have every faith that you will deliver the miracle that Bill is praying for

In the meantime, well done

 

[ianran]

On my last twin spark 1150 I had a broken connection in the connector for the stick coil which gave the impression a stick coil was gone. Chang4ed the coil great for a 10 mile run then back missfiring. This was intermittant giving smooth running and then lots of farting and popping. Steve Scriminger spent half a day trying to set the bike up untill he found this problem.
I know this is a bit left field of your work so far but Id gone down the throttle body route etc until I got here. Happy hunting,

 

[roddy]

......(no doubt all sharing the same spanner)....

ur ye sure they put that spanner back in the box an it's not bouncing about the insides

 

[waterloo700]

See, that's why you should never throw anything away

I beg to differ - you obviously never met my first wife

 

[ChrisH Kerry]

I beg to differ - you obviously never met my first wife

What - you threw her away?

 

[waterloo700]

What - you threw her away?

It was self preservation

 

[Fanum]

Lambda sensor arrived this morning, and it looks right (fits the Y piece I've been scrubbing away at for the last day to tidy it up anyway).....going out with a big hammer and a small hammer (for the more technical bits ) to get it fitted in a minute

£17.75 and delivered inside 48 hours......Quite impressed

 

[Uncle Rob]

Lambda sensor arrived this morning Quite impressed

even more so if it sorts your problem