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Grim

Persistent left cylinder misfire

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56 minutes ago, Weegie said:

Gotcha docc I see on the data sheet that the switching load is 35A but the rated load is 20A, that's sorta misleading

You bet! And relays like this get sold as "35 amp" relays. It is totally misleading. One of the reasons the Best Relay thread is so long. The other was how steep that learning curve was for me. At this point, it would not shock me that what Grim is wrestling with is not a single source problem, but a combination of additive issues. Once sorted, these challenges often lack the satisfaction of a particular "Eureka!" moment, yet leaves us with an exceedingly well sorted V11 . . .

Hang in there, Grim! You're on the right track and doing a lot of things right!

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1 hour ago, docc said:

@Weegie 

@Grim  Those compression numbers seem fine. Certainly symmetrical. If your battery went flat that quickly, perhaps getting it well conditioned and swapping the relays (3<->5) is worth the small fuss. Otherwise, I still ponder about grooming your exhaust, getting all lined up and fully seated at every joint. The last time I had to set my air screws very much differently, I found the intake vacuum taps had loosed up enough to cause trouble.

Ok, I have had some success.

I swapped back in a Siemens relay, but noticed no difference.

I wound the throttles back, disconnected choke and made sure I still had 157mv, yes I did.

I went for 1 turn out on the newly cleaned air screws.

I took off, and put back on the exhaust, I have this slight issue where the gaskets seem too thick, resulting in the crossover pipes not meeting the little nubs on the headers, but i can't compress them any more with the head nuts. Still, it all went back together.

I took off the throttle sync rod and wire brushed and oiled the slider mechanism. ( I am using a locknut on it)

I was thinking, I know what I (rightly or wrongly) want here, I want the right hand TB idle value to start off at 450mv.

I did that.

Ok got some calipers  in between the right hand throttle stop plates, got 4.7mm. 

 I went to the left and wound the screw out to achieve 4.7mm between the throttle stop plates.

I then connected the left side of the sync rod, and hovered over the bike and carefully wound the nylon knob till the left hand side would pop on the ball joint without moving the idle off 450mv.

So I definitely had the idle at 450mv and at least the same exact gap on the right, and the rod had not altered the idle yet.

 Started her up and... Running nearly balanced from the get go! Got it hot and wound it up to 3k, slightly too much air on the right, adjust the knob to perfect sync.

Back to idle and... Slightly lumpy, very slightly. I'm going to live with that and not tidy it up with the air screws.

Thank you one and all, thanks for the help 

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20 hours ago, Grim said:

 Thanks for you continued interest.

 

1. I will tomorrow, couldn't get a compression tester until then.

2. Left is, have another in the post from (kindly donated by Stewgnu) so soon the right will be.

3. I could, won't it just not run at all on that cylinder?

4. Right now, I don't *think* so. I am feeling like if the right is pulling more air and the screw is closed, then it would make sense that the butterfly was open more that the left at idle? I want to be in a position to open both air screws the same amount, therefore the right butterfly needs to close.  I think...

4 . Don't feel anything , know .

 The throttle plates must be the same degree of opening . You must adjust the idle air screws to maintain balance . This is only going to work if everything else is perfect .

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51 minutes ago, gstallons said:

4 . Don't feel anything , know .

 The throttle plates must be the same degree of opening . You must adjust the idle air screws to maintain balance . This is only going to work if everything else is perfect .

See above, I got it running pretty well, I used a modified version of your idea, so thank you very much for the inspiration and guidance.

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Great news, Grim! :thumbsup:

(Note that gstallons corrected the 450 mV to 540 mV. Likely give you a more stable, albeit higher, idle.)

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Let us know when you are completely satisfied with your repairs . 

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23 minutes ago, gstallons said:

Let us know when you are completely satisfied with your repairs . 

Is this hypothetical?

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54 minutes ago, docc said:

Great news, Grim! :thumbsup:

(Note that gstallons corrected the 450 mV to 540 mV. Likely give you a more stable, albeit higher, idle.)

Oh, bugger. It's idling over 1000 on the tacho, haven't checked in GuzziDiag. Might have to go over this again....

Have I invented a new procedure, BTW? 😉

 

Thanks for all your help.

 

In case anyone else is in despair and reads this, here are some things of note....

Things that were compounding the problem:

Jammed up white knob and sync rod thread would not allow easy adjustment to get rod on the ball joint without putting something else out of adjustment.

Fast idle had somehow crept in after setting idle screws, nudging the right throttle more open before attaching rod, make sure it doesn't nip up the throttle when tightening back up.

Possible exhaust leaks.

An ECU map that was richer than standard, making the left cylinder (which nearly closed) too rich at idle, therefore sooty.

Possible air leaks around perished rubber intake.

 

P.S. I saved myself £90 as well, which is how much a Guzzi specialist had quoted for a TPS reset, and I wouldn't have had the satisfaction of knowing I had done it myself, and knowing how everything was set.

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Quote

Fast idle had somehow crept in after setting idle screws, nudging the right throttle more open before attaching rod, make sure it doesn't nip up the throttle when tightening back up.

You are no doubt the first to have to deal with the fast idle thingy.. :grin:

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11 minutes ago, Chuck said:

You are no doubt the first to have to deal with the fast idle thingy.. :grin:

I was well prepared for releasing it, not letting it interfere with the TPS, making sure it was well out the way... Just didn't quite realise that tightening it back up would wind it on a tiny amount behind my back...

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12 hours ago, Grim said:

Is this hypothetical?

You know it !

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That white knob is difficult to turn for a reason . I am going to have to make a new instruction procedure and I left out some things concerning the fast idle kicker .

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6 hours ago, gstallons said:

That white knob is difficult to turn for a reason . I am going to have to make a new instruction procedure and I left out some things concerning the fast idle kicker .

The yellow paint was all in the threads on mine, so it wouldn't turn at all. In my first attempt I thought it was turning, but then realised I had accidentally unwound the thread out of the ball joint on the right hand side!

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Just following up... I took my bike for it's MOT (uk annual test) today, not sure what I was expecting, but it feels like a new bike. The sheer amount of tinkering has (I think) beaten everything into submission.
 

  • No misfire on either cyclinder at idle
  • No hot idle cough or splutter
  • Smooth pull all the way to redline
  • Can hold at part throttle (anywhere) and it sits happily and smoothly
  • Drinks all the fuel....:(

So, all in all, doing all the tune up stuff, again and again until you get it right, makes a wonderful difference...
Had an entire family stop and marvel as I rolled past, kids shouting nice bike, I put this down to my wonderful rattle can paint job.....

tDmPMCW.jpg

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:thumbsup: Nothing wrong with a rattle can. All the work is in the prep. And... sometimes they just want you to act like you care. :huh2::oldgit:

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