Engine lacks power

[fraser61]

Hi everyone, just new to the Forum and Moto Guzzis. Been a biker all my life and have covered a couple of hundred thousand miles on two wheels, but had until recently only ridden Japanese hardware.

 

Background

 

Just become the proud owner of a 2004 Coppa Italia out of Florida, now with only 5,500 miles on the clock. Previously owned by another enthusiast, who removed the charcoal vent cannister, installed a K&N filter and re routed the tip over valve to be vertical (not yet checked to see if it's still vertical). Has the factory Racing ECU and Titanium mufflers fitted, nice!!

 

It's just out of the local MG dealership where they set the tappets, corrected the fuel trim and set the ECU for the mufflers.

 

Problem

 

Which was present before the service and is still present is that the engine feels like it is running "slightly" roughly below 3,000rpm, I say slightly as I'm still not use to the V Twin feel, but between 2,500-3,000rpm the engine periodically misses a beat. That's to say I'm going along and I get a push back JUST LIKE it's just missed a complete firing cycle, although I'm inclined to believe it's fueling related, due to the overall rough feeling when running, as it's not misfiring.

 

I've checked the Iridium plugs and they are clean and gapped correctly.

 

So I'm left wondering if anyone has any ideas what may be going on?

 

Thanks in advance for your thoughts.

 

Fraser

 

1979 Land Rover Lightweight

1994 Land Rover D-90

2004 Coppa Italia

2005 Triumph Thruxton

2006 Kawasaki ZX-10R

2007 Suzuki DR650

[Kiwi_Roy]

That's to say I'm going along and I get a push back JUST LIKE it's just missed a complete firing cycle, although I'm inclined to believe it's fueling related, due to the overall rough feeling when running, as it's not misfiring.

 

Oh no, the Italian sneeze

 

I opened my valve clearences up and it seemed to get rid of most of that.

But wait for someone much wiser than me on this issue.

Congratulations on the new bike.

Roy

[docc]

You've got two Land Rovers and a Triumph and you're wondering why your Guzzi is glitchy?

 

No, seriously, there are a whole series of little things that will get it running better and better. It's likely not one major thing.

 

She's just askin' for more love . . .

[gstallons]

You've got two Land Rovers and a Triumph and you're wondering why your Guzzi is glitchy?

 

No, seriously, there are a whole series of little things that will get it running better and better. It's likely not one major thing.

 

She's just askin' for more love . . .

 

 

HAH !

[jrt]

Docc's in fine form tonight.

 

You're running the bike at too low RPMs. Keep it (mostly) above 4K- anything less is really lugging the motor and not good for the driveline.

Not sure why you or we get the 'sneezing', but mine has occasionally done it too at low rpm (so I'm a hypocrite). Setting the valve lash to Euro specs and using a Stucchi crossover has really about cured it.

[NPS]

Which was present before the service and is still present is that the engine feels like it is running "slightly" roughly below 3,000rpm, I say slightly as I'm still not use to the V Twin feel, but between 2,500-3,000rpm the engine periodically misses a beat. That's to say I'm going along and I get a push back JUST LIKE it's just missed a complete firing cycle, although I'm inclined to believe it's fueling related, due to the overall rough feeling when running, as it's not misfiring.

 

 

It is worth checking that the your plug caps have no cracks and leads are in good condition. I once had a misfire similar to what you describe and was due to a cracked NGK plug cap. At night you could try spraying a mist of water around the ignition leads, caps and coils and see if you can see any arks(shorts).

[grossohc]

Docc's in fine form tonight.

 

You're running the bike at too low RPMs. Keep it (mostly) above 4K- anything less is really lugging the motor and not good for the driveline.

I agree, guzzis dont like low revs so treat it like a 2 stroke

[fotoguzzi]

Docc's in fine form tonight.

 

You're running the bike at too low RPMs. Keep it (mostly) above 4K- anything less is really lugging the motor and not good for the driveline.

I agree, guzzis dont like low revs so treat it like a 2 stroke

 

I cured similar symptoms with a Mistral cross over, made all the difference. I can cruise thru town at 3k no problem but she sings a whole new aria above 5k rpm.

 

[Buzzard]

Try running a ground wire fom your voltage regulator to the engine cases. This simple fix cured my bikes low rpm sneezes.

[Streethawk]

Docc's in fine form tonight.

 

You're running the bike at too low RPMs. Keep it (mostly) above 4K- anything less is really lugging the motor and not good for the driveline.

I agree, guzzis dont like low revs so treat it like a 2 stroke

 

Well said. Coming from Japanese bikes and inline or v-fours myself, took some getting used too, but the bike likes being run in the higher RPM's.

[Tom M]

Welcome to the forum Fraser. As others have said you should be cruising at about 4k rpm. If you're getting the 2500rpm "cough" when you're pulling away from a stop it could mean that your bike is running a little lean. If that's the case you might want to get back to the dealer who did the tuning and let them know about it. If MPH Cycles did the work it was likely done right, but if it was done by another shop that doesn't have a long history with these bikes like MPH the valves could be too tight or the throttle position sensor or fuel trim could be off. These bikes seem to run better with more valve lash than the manual calls for, and a few here have had inexperienced dealers set their fuel trim way too lean while trying to compensate for a poorly adjusted TPS. You might want to check your exhaust for leaks at the heads and front crossover too.

 

Hope this helps...

[fraser61]

Thanks everyone

 

For the technical responses and even the untamed wit, which was on the mark and pretty true.

 

I will take it back to MPH who did the original tune up, as it would seem further fiddling is required, will advise IF they manage to fix it and what the fix(es) was/were.

 

Meanwhile I'm off out for a blast on the Triumph, happy, safe riding.

 

Fraser