General Category > General Discussion

Need help and advice

(1/7) > >>

willowstreetguzziguy:
My 2008 1200 sport was running fine except for half throttle surging and backfiring between 3000 and 5000 RPMs.So I had an appointment set up today with a Moto Guzzi dealer. All I wanted them to do is check the throttle bodies and see if there was an updated map that could be installed that might help cure the surging and backfiring.

After their first attempt, the bike was running worse. The back fairing was even worse. They said there wasn’t much needed as far as the balancing of the throttle bodies but there was a rubber cap missing on one of them that they replaced.

So I took it back and explained the situation and after their second attempt, they noticed that the “sacred screw” had somehow at some point in time, had been turned all the way in! They said they backed it out to where they thought it should be, but couldn’t guarantee anything and then adjusted the throttle bodies again. After taking it out for a test ride, the bike stalled several times and was idling at around 1000 RPMs

Going back again, they tried to adjust the idling at the throttle grip and now it’s fluctuating idling anywhere between 1200 and 2000 RPMs. (it’s no longer stalling) It was at the end of the day so I rode it home. The bike is backfiring whenever I let off the throttle at any rpm. It’s running worse than it ever has!

On the ride home, I stopped by a friend of mine who is experienced with motorcycles, once he learned that the sacred screw was turned outward, and listened to my bike going down the street, he said I would turn the screw back into where it originally was and see what happens. And adjust it from there.

I’m not quite sure the location of that screw if it’s on both throttle bodies or just the left one? The service guy pointed into the left throttlebody. Does anybody have any advice that will help my bike? You can imagine how bummed out I feel!!!

Tkelly:
Maybe a tps issue?

willowstreetguzziguy:

--- Quote from: Tkelly on August 27, 2026, 07:21:25 PM ---Maybe a tps issue?

--- End quote ---

Let me first say that the dealer originally spent about an hour working on the bike. And charged me for that amount. The second and third times he worked on it amounted to probably three hours of time which he did not charge me. I could tell that they couldn’t wait to get me out the door because the longer they worked on my bike the more money and time they lost. I left and rode home in torrential rain with it running terribly. So my question is…If it is a TPS issue… Would you
1. Call the dealer up and explain the issue and how badly it’s running and see if they can try and fix it for a fourth time?
2. Go to another dealer and see if they’re able to figure out the problem on their own?

willowstreetguzziguy:
Maybe I should call the dealer tomorrow morning and say…

“Ever since you backed the sacred screw out and synchronized the throttle bodies, it pops considerably more and surges between 3,000 and 5,000 RPM. It actually ran much better with that screw all the way in. Could the TPS baseline now be incorrect because the bike had been set up around that screw position years ago?”

Any thoughts?

CoolBreezeBreva:
Where do you live? If near Ohio go to Cadre Cycle. If you're in the Northeast go to Hamlin Cycles. Either of these should be able to sort. If not maybe get a set of used throttle bodies off of Ebay or something and put them on and go from there. How is the compression on the motor? Have the plugs recently been changed? Best advice I can come up with off the top of my head

Navigation

[0] Message Index

[#] Next page