Poor running once over 5000 rpm

[Guest v11rider]

Haven't had much experience with my 2002 V11 Sport since I got it just before Christmas.

To my great disappointment the bike behaves like it's loosing power and then getting it back once I pass the 5000 rpm point. The bike's sitting in the repair shop for now but the shop doesn't specialize in Guzzi's. They suggest a trial and error approach. Has anyone experienced something similar?

Any suggestions of where to start?

Just remembered- idle a bit unsteady and the spark plugs came out a little on the black side.

 

 

 

 

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Achilles

 

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Update 2/14

 

Many thanks for your quick replies guys but I'm afraid the problem wasn't made clear enough.

The poor running happens after the 5K point all the way up to the red rpm zone.

It feels like the bike is momentarely without fuel or spark then for a few seconds works properly then another hiccup and so on.

[Guest ratchethack]

Achilles, welcome, my friend! I've always admired your remarkable speed, strength, stamina, and skill on the field of battle. Gotta keep an eye out for those arrows from behind on the heel, though.

 

The V11 motor has a characteristic "dip" on the torque curve at 4500 RPM. This is not necessarily where you want a torque dip. The way I dealt with it is to install a Stucchi crossover, which didn't eliminate it by any means, but "fills it in" noticeably. I think the torque curve is raised by 3-4 lbs/ft. at the low part of the "dip". There are countless alternative go-faster approaches that may (or may not) help beyond this. You quickly get into the "how much time and money do you want to spend?" questions. Many seem to have their own "magic bullet" that they believe in, but for the most part, if you just want to enjoy the Guzzi for it's own unique "personality", IMHO it's best to think of this as another "character feature", and not expect serious torque unless you keep it in the power band above 5K RPM.

 

Plugs normally tend to show a black "shadow" on the tower closest to the exhaust valve.

 

BAA, TJM, & YMMV

[BRENTTODD]

The V11 motor has a characteristic "dip" on the torque curve at 4500 RPM. This is not necessarily where you want a torque dip. The way I dealt with it is to install a Stucchi crossover, which didn't eliminate it by any means, but "fills it in" noticeably. I think the torque curve is raised by 3-4 lbs/ft. at the low part of the "dip". There are countless alternative go-faster approaches that may (or may not) help beyond this. You quickly get into the "how much time and money do you want to spend?" questions. Many seem to have their own "magic bullet" that they believe in, but for the most part, if you just want to enjoy the Guzzi for it's own unique "personality", IMHO it's best to think of this as another "character feature", and not expect serious torque unless you keep it in the power band above 5K RPm

 

 

 

Plugs normally tend to show a black "shadow" on the tower closest to the exhaust valve.

 

BAA, TJM, & YMMV

 

yep

[GuzziMoto]

I'm surprised that someone hasn't already said this. Start with the basics, sync the throttlebodies, check the tps voltage, and make sure the valves are set right(not to what the manual might say, but to world spec. ie. .15 and .20 mm)

I sure others can add more. Guzzi's are sensitive to they way they are set up. There is a dip there, but it should barely be noticable.

Welcome to the club.

[Guest ratchethack]

Update 2/14

 

Many thanks for your quick replies guys but I'm afraid the problem wasn't made clear enough.

The poor running happens after the 5K point all the way up to the red rpm zone.

It feels like the bike is momentarely without fuel or spark then for a few seconds works properly then another hiccup and so on.

Now THIS is an entirely different kettle o' fish! Please elaborate. If the engine loses ALL fuel and/or ALL spark above 5K RPM, it obviously can't ever make it above 5K, let alone redline. Now if it's still capable of redline at 8K RPM, as you indicate, it must be that it either intermittently loses all fuel and/or all spark, and the rest of the time it runs fine, or that it's not losing spark at all, and there may be a fuel delivery problem. More clarification, por favor.

 

1. Are the poor running symptoms constant, intermittent, or merely occasional?

2. Is the motor backfiring or detonating (pinging)?

3. Are the poor running symptoms present only under full throttle, part throttle, or both?

4. What state of tune is the bike in? (please be as explicit as possible) What modifications made? PC III? Custom mapped?

[antonio carroccio]

...bla...and make sure the valves are set right(not to what the manual might say, but to world spec. ie. .15 and .20 mm)...bla...

Are you using this value for the valve of your V11?

 

I have done the regulation of the valve at mine V11 Le Mans last weekend, 0.2 in; 0.2 out.

 

I am using this value for a couple of years and no pinging at all inside there.

[Guest v11rider]

Now THIS is an entirely different kettle o' fish! Please elaborate. If the engine loses ALL fuel and/or ALL spark above 5K RPM, it obviously can't ever make it above 5K, let alone redline. Now if it's still capable of redline at 8K RPM, as you indicate, it must be that it either intermittently loses all fuel and/or all spark, and the rest of the time it runs fine, or that it's not losing spark at all, and there may be a fuel delivery problem. More clarification, por favor.

 

1. Are the poor running symptoms constant, intermittent, or merely occasional?

2. Is the motor backfiring or detonating (pinging)?

3. Are the poor running symptoms present only under full throttle, part throttle, or both?

4. What state of tune is the bike in? (please be as explicit as possible) What modifications made? PC III? Custom mapped?

 

Let's see what I can remember.

1. The poor running symptoms are intermittent but present once past the 5k point.

At any range below the 5k the bike behaves normal. I've ridden it with lights on, lights off still

it made no difference.

2. No backfiring or detonation.

3. Poor running symptoms are present under both part throdle and full. The bike still pulls inspite

of symptoms. I've ridden it up to 7.5k

4. The bike is stock. Got bike just before Christmas and had the basics done right away.

Valves were adjusted according to mannual, 10w40 synthetic oil was put in, oil filter changed,

dealership was out of fuel filters so that was left for later, air filter changed too.

5. The idle is set around 1000 rpm but not really steady untill it reaches a good running temp.

6. Spark plugs were also replaced, the old ones were a little on the black side as if mixture were a

little rich.

[Skeeve]

Let's see what I can remember.

1. The poor running symptoms are intermittent but present once past the 5k point.

At any range below the 5k the bike behaves normal. I've ridden it with lights on, lights off still

it made no difference.

2. No backfiring or detonation.

3. Poor running symptoms are present under both part throdle and full. The bike still pulls inspite

of symptoms. I've ridden it up to 7.5k

4. The bike is stock. Got bike just before Christmas and had the basics done right away.

Valves were adjusted according to mannual, 10w40 synthetic oil was put in, oil filter changed,

dealership was out of fuel filters so that was left for later, air filter changed too.

5. The idle is set around 1000 rpm but not really steady untill it reaches a good running temp.

6. Spark plugs were also replaced, the old ones were a little on the black side as if mixture were a

little rich.

 

Check your grounds. Intermittent high rpm misses are usually electrical; either grounds or bad coils. [Not that I'm an expert; just read a lot of motorcycle "letters to the mechanic" articles over the years... ]

[Guest ratchethack]

Let's see what I can remember.

1. The poor running symptoms are intermittent but present once past the 5k point.

At any range below the 5k the bike behaves normal. I've ridden it with lights on, lights off still

it made no difference.

2. No backfiring or detonation.

3. Poor running symptoms are present under both part throdle and full. The bike still pulls inspite

of symptoms. I've ridden it up to 7.5k

4. The bike is stock. Got bike just before Christmas and had the basics done right away.

Valves were adjusted according to mannual, 10w40 synthetic oil was put in, oil filter changed,

dealership was out of fuel filters so that was left for later, air filter changed too.

5. The idle is set around 1000 rpm but not really steady untill it reaches a good running temp.

6. Spark plugs were also replaced, the old ones were a little on the black side as if mixture were a

little rich.

Hm. A 6 year old V11 just getting it's first miles?! This puts things in a new light. The distinct possibility of the effects of bad fuel settling into the system, potential sediment in the tank (internal coating flaking, somebody put something nasty in, etc.!), fuel lines, and gummed injectors all come to mind. You can get a high quality fuel filter from most any good auto parts supplier at a lower cost than thru most Guzzi parts suppliers. We have the part number crossed here somewhere. I'd try this as a first step (if you're gonna do this anyway, IMHO it ain't a bad idea, considering) and if this doesn't do it, consider removing the electric fuel tap on the LHS of the tank for a gander at the strainer. Next, I'd test the pressure output of the fuel pump and replace if not up to spec. Finally, I'd suspect the possibility of gummed-up injectors and go after that one.

 

The good news is that it's more than likely something simple and fairly easily remedied.

 

I'd get the idle up to 1100-1200 RPM to ensure adequate oil pressure. This will help your idle smoothness.

 

That's about all I've got at this point. Let us know how it goes, and good luck.

[Tom M]

Lots of flaky electrical problems reported here turn out to be relay related. The first thing that I'd do is replace the fuel pump relay, making sure there's no corrosion and the terminals are tight. Dan is the man for relays. http://www.dpguzzi.com/relay.htm

[raz]

Lots of flaky electrical problems reported here turn out to be relay related. The first thing that I'd do is replace the fuel pump relay, making sure there's no corrosion and the terminals are tight. Dan is the man for relays. http://www.dpguzzi.com/relay.htm

I agree, I friend of mine had sympthoms very similar to yours and it went away when swapping relays. Note that you could swap all similar relays around to check it out quick. Then, if that was it, replace ALL of them because Dan's (or Ryland3210's) is cheap and stock relays are flaky. Both of them will ship to Greece and postage is not much since it fits in an envelope.

[Guest v11rider]

I agree, I friend of mine had sympthoms very similar to yours and it went away when swapping relays. Note that you could swap all similar relays around to check it out quick. Then, if that was it, replace ALL of them because Dan's (or Ryland3210's) is cheap and stock relays are flaky. Both of them will ship to Greece and postage is not much since it fits in an envelope.

 

Good idea. Relays are dirt cheap anyway. Even if the problem isn't resolved I'll have that area

covered for sure. I've already sent an email to Dan. I'll swap all similar relays for a quick check

and I'll also check my grounds first thing on Monday since the bike's already in the shop.

[Guest v11rider]

Lots of flaky electrical problems reported here turn out to be relay related. The first thing that I'd do is replace the fuel pump relay, making sure there's no corrosion and the terminals are tight. Dan is the man for relays. http://www.dpguzzi.com/relay.htm

 

 

It was a relay problem indeed. I've just received new set of relays from Dan and the problem

vanished.

Thanks for the tip. Dan was quicker than a v11 on this matter.

Bike's really happy now.

[raz]

It was a relay problem indeed. I've just received new set of relays from Dan and the problem

vanished.

Thanks for the tip. Dan was quicker than a v11 on this matter.

Bike's really happy now.

Great!