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03 Cafe Sport misfire


galaxiid

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Just been readin the thread "03 V11 runs like crap". In a similar manner my bike has an annoying miss, or sneeze, normally on a flat throttle say at 50km/hr and about 2-3k revs. The bike doesn't run like crap, but it is a niggle I have tried to sort out and haven't got to the bottom of. It's right at the speed you need to maintain through towns. You might also get the same miss backing off the throttle or just getting back onto it when entering corners. The miss/sneeze disappears altogether with an increase in throttle & engine speed.

 

The bike has a power commander 3 on it, plus mistrals & BMC filter. I have tried various settings on the PC3 to no avail.

 

No air leaks on the throttle body rubbers: been there done that.

Valve clearances at world settings.

 

Any links here to light technical reading? Or easy fix advice thanks.

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A dirty ignition switch can cause the ECU relay to drop out.

 

The sidestand might also be bouncing at that rev range you could try tying that in place.

 

Does it do the same with the PC3 disconnected?

 

Are there any other symptoms like tacho flickering?

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A dirty ignition switch can cause the ECU relay to drop out.

 

The sidestand might also be bouncing at that rev range you could try tying that in place.

 

Does it do the same with the PC3 disconnected?

 

Are there any other symptoms like tacho flickering?

Hi

 

in my experience, mot of these sneezes are caused by marginally weak fuelling. However all the above are equally valid reasons and can be easily checked out before looking at the fuelling. It's also worth check the TPS setting, in case this has drifted - there are many good threads on this forum to do this. If none of the above improve the problem, try the following:

- part some marks on your twistgrip so that you can readily identify ho far it is turned when the sneeze happens

- recreate the sneeze, and note tacho reading and twist grip position

- connect your PC to the power commander and with the twist grip in the sneeze position note the angle as given in the PC3 software. You can take the tacho reading as being slightly high ie 2200rpm is actually more like 2000rpm, or yuou can run the engine and on the PC3 screen, note the actual rpm when the tacho needle is in the same position as when the sneeze occurred

- now look at the mapping on your PC3 at the moment. If the sneeze occurred at 2000rpm and 20% throttle, just alter the fuelling at that point by +2. Upload this new map to your bike.

- take it out onto the road and see if this cures the problem. If not repeat the above and test again

 

You may have to make 5 attempts at it but you will cure the problem. It's the electronic equivalent of differnt jets, slides and needles being tried, but far, far easier.

 

Very important: (a) make sure your TPS setting is correct (B) the PC3 is set as per Dynajets calibration instructions. That way you will have a reference point in future. However even if you don't do either, this procedure will still cure it, and give you a better midrange too. V11s are set very weak between 20 and 40% and 2000 to 3000 rpm, this causes the sneeze.

 

My V11 runs K&N type cones and Mistrals and needed +6 in at least 4 points to run well, but now it is very fast in the midrange and more economical too.

 

Hope this helps

 

Guzz

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Hello, When in doubt, replace the tps sensor! My 03 Rosso has a cough just when the tempertures get into the 90's at 3000 rpm, my 02 EV ran very bad above idle when the engine warmed up, replaced the tps and she runs excellent. I used the Harley Davidson tps, much cheaper that the Guzzi and is the same manufacture. They are different part numbers, but I doubt if you can feel the difference between the two when riding.

 

Just a thought,

Mike

 

 

Just been readin the thread "03 V11 runs like crap". In a similar manner my bike has an annoying miss, or sneeze, normally on a flat throttle say at 50km/hr and about 2-3k revs. The bike doesn't run like crap, but it is a niggle I have tried to sort out and haven't got to the bottom of. It's right at the speed you need to maintain through towns. You might also get the same miss backing off the throttle or just getting back onto it when entering corners. The miss/sneeze disappears altogether with an increase in throttle & engine speed.

 

The bike has a power commander 3 on it, plus mistrals & BMC filter. I have tried various settings on the PC3 to no avail.

 

No air leaks on the throttle body rubbers: been there done that.

Valve clearances at world settings.

 

Any links here to light technical reading? Or easy fix advice thanks.

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Thanks for all the above very useful information. I will check all of them out.

 

Some answers: yes it has the standard crossover pipe.

no tacho does not flicker.

haven't tried disconnecting the PC3, but will now.

TPS settings were done by a supposed mechanic-technician last year and "dyno tuned" (for what it was worth) with no real difference in my view following the fitting of the BMC filter. But I got a pretty before/after graph with 91.1 HP on it :doh: I thought TPS setting was a bit beyond me.

 

Bugger my mac compuTer doesnt speak to the Power Commander!

 

I've put up with it till now as "character" but know there must be a simple solution somewhere. Bit irritating only.

 

I still bloody love this bike.

 

Thanks heaps for your suggestions

MG dyno .jpg

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Can anyone explain that graph for me?

 

I assume the highest blue line is the Horse Power following modifications and the red line as before and that the two lower lines are the before and after Air Fuel Ratios.

 

What is the significance of the dip in the AFR around 4100pm?

Is it usual for engines to slowly runner leaner at the higher revs as in this grah?

Why does he HP remain constant at the top end?

 

This not a criticsm of the work done to your bike, just me trying to understand things. If I had been given this gaph for my bike I would have added fuel round the 4100 point, but I suspect that is too simplistic.

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Bugger my mac compuTer doesnt speak to the Power Commander!

 

Try Parallels for Mac - I use it to run Windaes on some Macs I have. I run some mapping and charting (hillwalking / sailing) software and also have run CJs myECU controller and the Innovate LC1 s/ware on what is rapidly becoming a "left behind" MacBook. Later Parallels versions seem more efficient.

Be warned however - it does work best if you have loads of RAM and a fast processor tho'. Also you will need to faff about with usb settings.

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Bugger my mac compuTer doesnt speak to the Power Commander!

 

 

 

I still bloody love this bike.

 

Thanks heaps for your suggestions

 

I have my MBP partitioned to run windows just for the VDST program.

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Just been readin the thread "03 V11 runs like crap". In a similar manner my bike has an annoying miss, or sneeze, normally on a flat throttle say at 50km/hr and about 2-3k revs. The bike doesn't run like crap, but it is a niggle I have tried to sort out and haven't got to the bottom of. It's right at the speed you need to maintain through towns. You might also get the same miss backing off the throttle or just getting back onto it when entering corners. The miss/sneeze disappears altogether with an increase in throttle & engine speed.

 

The bike has a power commander 3 on it, plus mistrals & BMC filter. I have tried various settings on the PC3 to no avail.

 

No air leaks on the throttle body rubbers: been there done that.

Valve clearances at world settings.

 

Any links here to light technical reading? Or easy fix advice thanks.

 

It is not some big problem, mine does the same thing when hot.

Maybe it loves winter

 

When is fresh serviced phenomenon decreases.

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I'm very happy with my stock crossover. Regardless what silencers are mounted, stock, MIVV or the long and open Mistrals. Seriously no joking.

Hubert

The stock crossover is as loose as a goose. Should this contribute to the "sneeze"? I too cannot see any difference in replacing the stock crossover.

 

Yes it is a mild problem I do admit. It's not a lugging prob either, it occurs on a "flat" throttle, which is only an issue noticed when you are diddling along. Haven't had the chance to look at it yet. When I have spare time I tend to ride rather than fiddle, which is why it has gone on so long!

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Can anyone explain that graph for me?

 

I assume the highest blue line is the Horse Power following modifications and the red line as before and that the two lower lines are the before and after Air Fuel Ratios.

 

What is the significance of the dip in the AFR around 4100pm?

Is it usual for engines to slowly runner leaner at the higher revs as in this grah?

Why does he HP remain constant at the top end?

 

This not a criticsm of the work done to your bike, just me trying to understand things. If I had been given this gaph for my bike I would have added fuel round the 4100 point, but I suspect that is too simplistic.

I think you have it about right in your explanation. The HP line illustrates a constant growing train like push to the horizon=good. No real dips or bumps. That's about all I got out of it. All from checking TPS settings and installation of a BMC airfilter (cut the lid off the top too). And a fiddle with the PwrCommander. The fuelling at 4100 could be changed I guess. A bit of a pointless exercise at the end of the day, dynoing it I mean. I would have had more faith if I knew the technician had a bit of Guzzi know-how.

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